Naked Science Forum
Non Life Sciences => Technology => Topic started by: alancalverd on 30/04/2021 09:44:32
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EoN supplies about 15% of the UK's electricity. Their current advertisement says they supply 100% renewables. But right now, and for the past month, only about 12% of the total UK supply has been from renewables, and many smaller companies make the same claim.
How do they do it?
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Maybe their renewable content is averaged over a period longer than 1 month?
- When wind/solar is scarce, EoN "borrow" some fossil electricity from other suppliers
- And when wind/solar is plentiful, EoN "pays it back" by having the other suppliers use more renewables?
or maybe "100%" is just "96% rounded off to the nearest 10%"?
...But if "100% renewables" is what their headline says, there seems to be some weasel-wording going on!
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However long your average, it's going to be difficult to reach 100% of any variable. As far as the UK grid is concerned, 40% renewables is about the best you can expect, provided nobody else sells it and you don't supply electricity at night!
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EoN supplies about 15% of the UK's electricity. Their current advertisement says they supply 100% renewables. But right now, and for the past month, only about 12% of the total UK supply has been from renewables, and many smaller companies make the same claim.
How do they do it?
I think they do it by some sort of offsetting with low carbon emission areas , but would need to check details.
Potentially dubious practice in my opinion.
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EoN supplies about 15% of the UK's electricity. Their current advertisement says they supply 100% renewables. But right now, and for the past month, only about 12% of the total UK supply has been from renewables, and many smaller companies make the same claim.
How do they do it?
I think they do it by some sort of offsetting with low carbon emission areas , but would need to check details.
Potentially dubious practice in my opinion.
Buying Carbon Credits?
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Domestic demand today is about 17 GW and wind is running at 5% of peak capacity - 730 MW shared between all the suppliers! Where is EoN getting the rest of its 2.6 GW (15% of total supply, remember) of renewable energy from? Not solar, I hope, because the sun is going down.....
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Domestic demand today is about 17 GW and wind is running at 5% of peak capacity - 730 MW shared between all the suppliers! Where is EoN getting the rest of its 2.6 GW (15% of total supply, remember) of renewable energy from? Not solar, I hope, because the sun is going down.....
That cannot be right Alan, 17gw is only 1700 10mw turbines.
https://www.siemensgamesa.com/en-int/newsroom/2019/01/new-siemens-gamesa-10-mw-offshore-wind-turbine-sg-10-0-193-dd.
I know they are not continuous or always at peak but that would mean we only need about 8000
https://theswitch.co.uk/energy/guides/renewables/wind-energy#:~:text=Wind%20energy%20UK%3A%20the%20numbers%20%20%20,%202%2C450%20sites%20%20%2026%20million%20
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I estimated domestic demand as about 50% of the actual demand at the time I was writing - best estimate from government figures is domestic electricity use accounts for about half of the total. 730 MW was the entire wind output at that moment.
The problem with wind generators is they rarely deliver more than 30% of rated output, generally 15 - 20% averaged over a year. Right now we have 15GW of installed wind capacity but only 0.5 GW of actual output. As I write, 62% of UK electricity is being generated from gas and 20% nuclear.
So where is my "100% renewable" electricity coming from?
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So where is my "100% renewable" electricity coming from?
It’s coming from EoN buying Renewable Energy Certificates. These are traded and can be used to give the appearance that the energy all comes from renewables. Problem is, they can be traded like carbon offsetting.
https://energypost.eu/stop-trading-renewable-energy-supply-certificates-speed-up-the-transition/
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Domestic demand today is about 17 GW and wind is running at 5% of peak capacity
You can also get carbon credits for regrowing a forest that got cut down a century ago. And trees continue growing even in light winds.
Of course, in some countries, they are cutting down a diverse rainforest ecosystem today so they can get the carbon credits in 6 months by planting a monoculture.
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Domestic demand today is about 17 GW and wind is running at 5% of peak capacity - 730 MW shared between all the suppliers! Where is EoN getting the rest of its 2.6 GW (15% of total supply, remember) of renewable energy from? Not solar, I hope, because the sun is going down.....
It's going to be averaged over the month, maybe even longer. Don't forget although sometimes the wind and solar drops below the average output, that means that other times it overproduces above the average, so the fossil plants shutdown. The climate doesn't care if you produce more CO2 some days more than others, it's the average that matters over the year.
In fact the lowest that National Grid have reported in the last month that I could find was 16% on April 14th:
https://twitter.com/NGControlRoom/status/1382357399256858626
And was 58% on April 6th:
https://twitter.com/NGControlRoom/status/1379458291810627591
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An average cannot reach 100%, which is what the advert claims. Domestic users don't only use electricity when the wind is blowing.
On Tuesday #gas generated 55.9% of British electricity, more than nuclear 17.4%, biomass 6.9%, imports 6.7%, solar 5.6%, coal 3.6%, hydro 2.5%, wind 1.4%, other 0.0%
That's 16.4% renewables over 24 hours (most of the "import" is French nuclear). Assuming the sun don't shine out of the grid's backside, that only gives me 11% of my consumption at night. But EoN promise 100% with no qualification!
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100% of the renewable power generation you bought, happened, and the renewables certificates ensured no double selling.
And the day before yesterday was 29% renewables:
https://twitter.com/NGControlRoom/status/1388155603407757315
Which more than made up for it. 🤷♂️
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So all the stuff I used was renewable, and my neighbor, on the same grid but with a different billing company, got different colored electrons?
EoN's boast is that all the mains electrons coming into my house at any time are from renewable sources, even when those sources are not working. That's greenwash and bullshit of the worst kind.
Join E.ON where all our customers get 100% renewable electricity as standard, at no extra cost.
You can't "make up for it" because EoN don't offer any domestic energy storage capacity.
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my neighbor, on the same grid but with a different billing company, got different colored electrons?
Marking electrons with different colors is an accounting exercise.
- Accounting can also be done by computers without going to the trouble of colouring-in individual electrons.
In reality, because the UK grid runs on Alternating Current (AC), you are only ever consuming your own electrons (the net electron movement during an AC cycle is zero, regardless of how much AC current you draw).
- And if you sign up with EoN as your electricity retailer, Eon now "owns" all the electrons in your wires - and charges you for the privilege of using them.
See: https://en.wikipedia.org/wiki/Alternating_current
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Around here we get a lot of renewable energy from hydroelectric.
https://en.wikipedia.org/wiki/List_of_U.S._states_by_electricity_production_from_renewable_sources
While the nation as a whole isn't that great, a few of the states have over 75% renewables, often with more than half of the electricity from hydroelectric sources. I'm actually puzzled where all the non-renewable electricity is coming from. :o
In theory a good hydroelectric source can store significant amounts of energy during off-peak hours, and utilize that energy during peak hours.
Around here we have a strong seasonal water flow, but also a lot of homes are 100% electric, so using electric heat during the winter when water flow is highest.
Some electricity intensive businesses such as aluminum production are encouraged to organize shifts around purchasing off-peak power, often at a significant discount.
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And if you sign up with EoN as your electricity retailer, Eon now "owns" all the electrons in your wires - and charges you for the privilege of using them.
Not quite. They are charging for the electrical energy used to push them to and fro. Within living memory my grandfather's house was on 240V DC mains, where the London Electricity Company was indeed charging per electron.
So my complaint the insn't that my electrons aren't green, but that they are being waggled by multicolored joules.
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Around here we get a lot of renewable energy from hydroelectric.
Trouble with hydro electric is there are few sites on the planet with a good enough river flow and suitable terrain to make it worth while. Most high level dams have a pitiful river flow, most rivers with suitable flow do not have terrain that is amenable to producing a reservoir. High level reservoirs do make excellent locations for pumped power storage, Dinorwig would look tiny by comparison.
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So all the stuff I used was renewable, and my neighbor, on the same grid but with a different billing company, got different colored electrons?
EoN's boast is that all the mains electrons coming into my house at any time are from renewable sources, even when those sources are not working. That's greenwash and bullshit of the worst kind.
Join E.ON where all our customers get 100% renewable electricity as standard, at no extra cost.
You can't "make up for it" because EoN don't offer any domestic energy storage capacity.
None of that matters. What matters is:
1) my money ends up in the hands of renewable power producers
2) none of my money ends up paying for fossil fuel production
I don't actually care whether my power producer pays fossil fuel producers or the grid occasionally when they underproduce provided they then get paid back on another day in the year by the fossil fuel producers or the grid when they overproduce, provided my money or power use doesn't increase the amount of carbon produced.
Given the state of the grid today, it doesn't.
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2) none of my money ends up paying for fossil fuel production
Not production, but combustion. Never mind the money: the advert says
All our customers' homes and businesses get 100% renewable electricity, at no extra cost.
which is obviously at variance with The electricity supplied to homes and businesses comes from the National Grid and DNOs.
In other words, they are charging me for renewables but supplying whatever comes down the line, which has been 80% gas and nuclear for most of April.
That's deliberate misrepresentation.
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Do you also complain to your bank that they don't give you YOUR money back, they actually give you somebody else's?
Because if not, you're a hypocrite.
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If more people sign up with EoN, or more electricity companies offer a "green" contract like EoN, that will push the industry to deliver greater supplies of renewable energy.
Hopefully, someone is checking the books to ensure they don't overpromise (when averaged over a suitable timescale).
- Maybe someone should define a reasonable timescale...
- Is a year a reasonable timescale? That covers the main periodicities in renewable production.
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No average supply of A + B can reach 100% A unless B= 0 always. So they would have to switch off my supply if the wind stops at night. They don't. Indeed they can't because the domestic supply contract is for 97% uptime at any level of demand from zero to 100 amp.
Disinfectants claim to "kill 99% of household germs" because a 100% claim would be provably dishonest. Is it too much to expect the same from an electricity supplier?
Afterthought: when a footballer gives 110%, does that mean he plays after the whistle? Isn't that against the rules?
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Do you also complain to your bank that they don't give you YOUR money back, they actually give you somebody else's?
Because if not, you're a hypocrite.
They don't pretend to, or imply it as a virtue in their adverts.
But if they put somebody else's documents in my security box, and gave my valuables away to anyone who wanted them, I would have legitimate grounds for complaint.
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As I said, you're a hypocrite.
Do you have even have green electricity from EON?
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Nope its all bollocks Alan, at the moment in the UK something like 5 percent of our energy need come from sources not conventional. I see the UK has signed up to 85 percent reduction in 20 years, given it has taken 10 years to get 5 percent, This is what is called window dressing .
I do not use such language frivolously either.
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Actually Alan your a fascist.
https://www.theguardian.com/environment/2021/may/04/blustery-bank-holiday-helps-windfarms-set-new-clean-energy-record
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As I said, you're a hypocrite.
Do you have even have green electricity from EON?
I don't see any evidence of hypocrisy on my part.
I buy my electricity from EoN, but it is obvious that they are not getting 100% of it from renewables because the lights don't go out at night when there is no wind. That's where the hypocrisy lies.
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Actually Alan your a fascist.
https://www.theguardian.com/environment/2021/may/04/blustery-bank-holiday-helps-windfarms-set-new-clean-energy-record
If I'm a fascist when the wind blows, how come everyone else isn't? Do I detect a non sequitur, or is this real eco-fascism ?
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Actually Alan your a fascist.
https://www.theguardian.com/environment/2021/may/04/blustery-bank-holiday-helps-windfarms-set-new-clean-energy-record
If I'm a fascist when the wind blows, how come everyone else isn't? Do I detect a non sequitur, or is this real eco-fascism ?
Err, well I was being sarcastic, as a state of "eco" government is deserving of in the state of affairs today. On the best day ever 10 percent of our energy comes from renewables. Blowing their trumpet over a failure.
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Nope its all bollocks Alan, at the moment in the UK something like 5 percent of our energy need come from sources not conventional. I see the UK has signed up to 85 percent reduction in 20 years, given it has taken 10 years to get 5 percent, This is what is called window dressing .
I do not use such language frivolously either.
What's important isn't straight-up energy, it's the amount of exergy:
https://en.wikipedia.org/wiki/Exergy
In other words, just because total thermal energy production is some number of exawatt-hours or whatever, how much of that is actual usable energy?
To take the example of petroleum, a car is something like 20-30% efficient. So if you compare an electric car with a petrol car, the petrol car would seem to be enormously more energetic. But in reality, they have not that dissimilar range. So the exergy is in reality similar.
Or, to take another example, if you heat your house with an air-source heat pump, how much electricity is used compared to burning gas?
The point is, by wrongly, directly comparing electricity with thermal energy, you are WILDLY exaggerating the scale of the problem. By a factor of about three. So really we're more like 30% of the way there (roughly).
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Nope its all bollocks Alan, at the moment in the UK something like 5 percent of our energy need come from sources not conventional. I see the UK has signed up to 85 percent reduction in 20 years, given it has taken 10 years to get 5 percent, This is what is called window dressing .
I do not use such language frivolously either.
What's important isn't straight-up energy, it's the amount of exergy:
https://en.wikipedia.org/wiki/Exergy
In other words, just because total thermal energy production is some number of exawatt-hours or whatever, how much of that is actual usable energy?
To take the example of petroleum, a car is something like 20-30% efficient. So if you compare an electric car with a petrol car, the petrol car would seem to be enormously more energetic. But in reality, they have not that dissimilar range. So the exergy is in reality similar.
Or, to take another example, if you heat your house with an air-source heat pump, how much electricity is used compared to burning gas?
The point is, by wrongly, directly comparing electricity with thermal energy, you are WILDLY exaggerating the scale of the problem. By a factor of about three. So really we're more like 30% of the way there (roughly).
Not really, electricity looses about 30 Percent in transmission. Given that fossil fuel usage is mainly direct to the customer, you have to add 3/⁷ths more energy to electric before you start.
https://electrical-engineering-portal.com/total-losses-in-power-distribution-and-transmission-lines-1
Gas boilers are about 90 percent efficient, cars are 33 percent efficient. Electric vehicles are 80 percent efficient from electricity and air source heat pumps are 200 percent efficient, again from the juice supplied. But when you add in the losses for transmition, an electric car is about 55 percent efficient, similarly for the boiler the energy savings are not great.
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But when you add in the losses for transmission, an electric car is about 55 percent efficient
I heard that, in Australia, 70% of the people with an electric car have rooftop solar.
- So they don't need to burn extra carbon to charge their car, if they charge the car at home.
- And they may use less electricity during peak hour, if they use the car battery to supplement the household electricity consumption.
- It is during winter evening peak hour that electricity is likely to be most carbon-intensive, because gas turbines can be rapidly spun up to meet peak demands, on days when there isn't enough wind, and the Sun has gone down.
Reportedly, the Australian government first determined their policy: "We will not subsidize electric cars".
- Then they commissioned a study to prove that they had the right policy
- Has Politics ever used evidence-based policy?
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And they may use less electricity during peak hour, if they use the car battery to supplement the household electricity consumption.
You have hit upon the real purpose of an electric car: it makes the planet "greener" as long as you don't use it!
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And they may use less electricity during peak hour, if they use the car battery to supplement the household electricity consumption.
You have hit upon the real purpose of an electric car: it makes the planet "greener" as long as you don't use it!
Most cars don't get used most of the time, so that's OK.
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In that case we need to include storage inneficiencies too.
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The point is, by wrongly, directly comparing electricity with thermal energy, you are WILDLY exaggerating the scale of the problem. By a factor of about three. So really we're more like 30% of the way there (roughly).
Not really, electricity looses about 30 Percent in transmission.
Nope. In the UK, transmission losses were 7.5% as of 2017, and I'm imagining they're pretty similar in 2021.
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In that case we need to include storage inneficiencies too.
If you were storing energy from a coal-fired plant, then you would need to include storage inefficiency in calculating the CO2 output.
- But if the electricity from rooftop solar is being temporarily stored in a car battery, there is no extra CO2 output due to power lost in charging/discharging the battery.
- There is the additional possibility that stored rooftop solar power could displace peak-hour fossil power, reducing CO2 output.
electricity looses about 30 Percent in transmission.
n the UK, transmission losses were 7.5% as of 2017
This is only important if you are generating your power from CO2.
- If you are generating power from green sources, the transmission losses do not cause an increase in CO2 emissions.
- And if you are generating power from your own rooftop solar, the transmission losses will be a lot lower than 7.5%.
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You can also get carbon credits for regrowing a forest that got cut down a century ago. And trees continue growing even in light winds.
Good point. I haven't cut my lawn, and I have about 100 sq m of untamed thicket with all sorts of wild trees and shrubs growing on it, so I can burn as much AVGAS as I like and claim to be a zero-carbon aviator. Better still, if we don't cut the grass between the runways or the boundary hedge, we can claim the entire airfield as good for the environment.
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The point is, by wrongly, directly comparing electricity with thermal energy, you are WILDLY exaggerating the scale of the problem. By a factor of about three. So really we're more like 30% of the way there (roughly).
Not really, electricity looses about 30 Percent in transmission.
Nope. In the UK, transmission losses were 7.5% as of 2017, and I'm imagining they're pretty similar in 2021.
18%ish in the UK, I guess with it being a small distance in-between places.
https://www.ice.org.uk/knowledge-and-resources/briefing-sheet/electricity-transmission-and-distributionIn that case we need to include storage inneficiencies too.
If you were storing energy from a coal-fired plant, then you would need to include storage inefficiency in calculating the CO2 output.
- But if the electricity from rooftop solar is being temporarily stored in a car battery, there is no extra CO2 output due to power lost in charging/discharging the battery.
- There is the additional possibility that stored rooftop solar power could displace peak-hour fossil power, reducing CO2 output.
electricity looses about 30 Percent in transmission.
n the UK, transmission losses were 7.5% as of 2017
This is only important if you are generating your power from CO2.
- If you are generating power from green sources, the transmission losses do not cause an increase in CO2 emissions.
- And if you are generating power from your own rooftop solar, the transmission losses will be a lot lower than 7.5%.
Or wind farms, or solar plants, or energy storage area, or the losses from the contact resistance in your own roof.
We are not going to see massive reductions in energy needed without home insulation, heating and AC are massive drains. The point is that energy use is not going to plummet just because we switch to electric cars
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Actually, heat pumps generate 2-5 times as much heat as the electrical energy is used, and electric cars are much more efficient as well, so yes, overall energy use is indeed set to plummet. That's the whole point.
18%ish in the UK, I guess with it being a small distance in-between places.
If you mean: "Costs for the transmission and distribution of electricity typically account for 16-20% of the typical domestic electricity bill." that's not the same thing as efficiency.
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Actually, heat pumps generate 2-5 times as much heat as the electrical energy is used, and electric cars are much more efficient as well, so yes, overall energy use is indeed set to plummet. That's the whole point.
For the heat pump, do you have any real world experience from anyone for the 2 to 500percent efficiency? From what I have read it comes in at about 200 over the year. Problem is that at times when heating is most required during the winter the efficiencies are lower. Who needs central heating when it's 35 decrees C out side! I think the whole point is something like the heat exchanger for air changes, if your house is airtight enough you can save something like 90 percent of costs.
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18%ish in the UK, I guess with it being a small distance in-between places.
If you mean: "Costs for the transmission and distribution of electricity typically account for 16-20% of the typical domestic electricity bill." that's not the same thing as efficiency.
ah that make sense then
This difference in the generated and distributed units is known as Transmission and Distribution loss. Transmission and Distribution loss are the amounts that are not paid for by users
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Every part of the cost of generating and distributing electricity is paid for by the user. Who else? It isn't a charity!
It's wrong to talk about heat pumps "generating" 200% energy. They actually generate very little heat if the motors and pumps are efficient. What they do is move heat energy from place to place, and generally manage to move 2 - 3 times as much energy as they consume in doing so.
The source to drain efficiency of a car depends principally in the efficiency of the prime mover. In the case of an i.c. engine, it's around 40%. For the foreseeable future, it will be about the same for electric cars - the prime mover just happens to be somewhere else, polluting the upper atmosphere.
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For the foreseeable future, it will be about the same for electric cars - the prime mover just happens to be somewhere else, polluting the upper atmosphere.
It seems a pity that you can't foresee changes.
The rest of us recognise that renewables have been making a large, and increasing contribution for some time.
https://www.theguardian.com/business/2020/jan/07/renewables-beat-fossil-fuels-greenest-year-uk-energy
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Worth reading David Mackay's seminal book withouthotair.com/download.html. The last paragraph of p 238 makes the point.
The Guardian article, like so many, confuses electricity with energy. It only accounts for 25 - 30% of our energy consumption at most.
But we are wandering away from the subject here. The question is whether EoN are actually supplying me with 100% renewable electricity at all times, not some time inthe future but right now. Because they are charging me (and many others) for it.
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Actually, heat pumps generate 2-5 times as much heat as the electrical energy is used, and electric cars are much more efficient as well, so yes, overall energy use is indeed set to plummet. That's the whole point.
For the heat pump, do you have any real world experience from anyone for the 2 to 500percent efficiency? From what I have read it comes in at about 200 over the year. Problem is that at times when heating is most required during the winter the efficiencies are lower. Who needs central heating when it's 35 decrees C out side! I think the whole point is something like the heat exchanger for air changes, if your house is airtight enough you can save something like 90 percent of costs.
I don't have any first hand experience, but I've been following the technology.
For example, the Mitsubishi M-series reversible heat pumps apparently work particularly well for heating purposes down to low temperatures. There's graphs here:
https://www.greenbuildingadvisor.com/question/visualizing-mini-split-performance-data
So from the graphs, at 5F (-15C), the heat pump retains 80% of its nameplate COP (about 3.7 or so), which isn't bad. However, it also loses power output, 50% at 5F, but only loses 20% at 32 F (0C). The loss of power is generally a slightly bigger problem than the loss of efficiency.
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Fossil fuels decreased by 42%; Gas increased by 38%
I'm not quite sure how to interpret these two lines in the graph...
- Last time I checked, Gas was a fossil fuel (unless UK is using a very different gas than Australia...)
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I have a 160 sq m building heated by airsource heat pump with underfloor coils at 30°C and domestic hot water at 50°C.
When it works, the overall COP is certainly above 2 but the whole system is depressingly unreliable - the transition from physics to simple engineering in a refrigerator is brilliant, but the design of a modern heat pump has added expensive and fragile layers of programmable sophistication to a very simple principle.
I expect a refrigerator to maintain 5°C for 20 years, and they do. What I want is to maintain a well-insulated music studio at 18°C to keep the instruments in tune and the players awake. What have to buy is a gizmo that can deliver pretty well any temperature in any part of the room at any time of day, with different programs for each day, provided that a nursemaid is on call to check the feed water pressure, thermostat batteries, water grit filter is clear, no leaves sucked into the condenser, umpteen flow valves lubricated, diverter valve not seized.....
Years ago I built three clinics around the most sophisticated MRI machines on the market. Not a hint of trouble from the capital machinery, or the kitchen fridges, but in 10 years we never had the entire cooling and aircon systems all working properly at the same time.
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Fossil fuels decreased by 42%; Gas increased by 38%
I'm not quite sure how to interpret these two lines in the graph...
- Last time I checked, Gas was a fossil fuel (unless UK is using a very different gas than Australia...)
I think "science journalism" is an oxymoron, like "military intelligence".
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Years ago I built three clinics around the most sophisticated MRI machines on the market. Not a hint of trouble from the capital machinery, or the kitchen fridges, but in 10 years we never had the entire cooling and aircon systems all working properly at the same time.
I can't speak to the (un)reliability of the particular brand of equipment that was installed.
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Years ago I built three clinics around the most sophisticated MRI machines on the market. Not a hint of trouble from the capital machinery, or the kitchen fridges, but in 10 years we never had the entire cooling and aircon systems all working properly at the same time.
I can't speak to the (un)reliability of the particular brand of equipment that was installed.
If you get a small heat pump, a Heat recovery unit, an insulated and airtight home you can achieve a Cop of 30. I imagine these are the homes that cost 10 pounds a year to heat.
To compare to other "systems"
Say you have a heat pump rated at COP = 2.5 (maximum permitted under SAP)
Outside temperature 1C (so the heat pump may avoid frost), inside 21C
instantaneous heating by 20C
HRV providing 0.35 ach (volume of air is 202m3)
Energy recovered 293W (o.35x0.33x volumex63%x20C)
energy used 10W
COP = 29.3 (2930%)
This is a strong indication that it is far far easier to save energy than it is to produce
http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=3017#Comment_39416
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It's true that heat recovery is the key to energy conservation. Little point in using a heat pump to warm the air if you then throw away your asset by opening the window!
That isn't strictly a COP measurement since you can have an entirely passive HRU which returns 80% of exhaust heat with no power input - infinite COP? What you have done is simply improve the effective insulation of a ventilated building.
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Actually, heat pumps generate 2-5 times as much heat as the electrical energy is used, and electric cars are much more efficient as well, so yes, overall energy use is indeed set to plummet. That's the whole point.
18%ish in the UK, I guess with it being a small distance in-between places.
If you mean: "Costs for the transmission and distribution of electricity typically account for 16-20% of the typical domestic electricity bill." that's not the same thing as efficiency.
I guess that the discrepancy is due to power not supplied to the grid, such as emergency reserve and extra power supplied to the grid that the customers do not draw off.
https://en.m.wikipedia.org/wiki/Operating_reserve
That is a lot of energy.
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Cost and energy aren't the same thing. Energy use sets a floor for costs, but costs are usually more to do with paying personnel needed to do something.
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Cost and energy aren't the same thing.
This website suggests that costs of solar power have reduced by a factor of 5 in the past 10 years.
- The author looks at a few trends, and suggests that the production cost of solar energy declines by about 30% every time the industry doubles the capacity manufactured, due to the "learning curve" effect
- Lower costs means that the rate of manufacture is increasing; this model assumes that the rate of installed capacity is growing at 16% per year (compound growth).
- While the price of coal-power has not declined over the same period (and, if we are honest, the cost of ill-health due to coal power has increased over that time)
See: https://rameznaam.com/2020/05/14/solars-future-is-insanely-cheap-2020/
Of course, before we shut down all fossil power plants, we need to deal with the fact that the Sun shines longer in the Summer, and not at all, at night....
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Wind blows stronger in winter, and less in summer, and blows at night. In conjunction with grid batteries, vehicle to grid technology, and renewables from waste streams, it seems to me that the UK's electrical generation can go zero carbon.
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Wind blows stronger in winter, and less in summer, and blows at night.
Not true. "Surface" wind (anything below 1000 ft above local surface, i.e. the stuff that makes electricity) ) is strongly influenced by convective mixing, which is maximum when the sun shines. Persistent winter fog in the UK is due to the arctic anticyclone, with very little wind - and maximum electricity demand..
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Not true. "Surface" wind (anything below 1000 ft above local surface, i.e. the stuff that makes electricity) ) is strongly influenced by convective mixing, which is maximum when the sun shines.
So, you finally worked out that it's not powered by the rotation of the earth.
I guess that's progress.
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Wind blows stronger in winter, and less in summer, and blows at night.
Not true. "Surface" wind (anything below 1000 ft above local surface, i.e. the stuff that makes electricity) ) is strongly influenced by convective mixing, which is maximum when the sun shines. Persistent winter fog in the UK is due to the arctic anticyclone, with very little wind - and maximum electricity demand..
I disagree, but it appears that wind turbines have been specified up for this summer wind, meaning that they appear unable to harness the winter wind. Shore breezes are renowned anyway, land heats during the day and cools at night meaning the direction changes. Shores are probably very good for the namby pamby wind turbines we are installing
https://www.britannica.com/science/sea-breeze
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Wind blows stronger in winter, and less in summer, and blows at night.
Not true. "Surface" wind (anything below 1000 ft above local surface, i.e. the stuff that makes electricity) ) is strongly influenced by convective mixing, which is maximum when the sun shines. Persistent winter fog in the UK is due to the arctic anticyclone, with very little wind - and maximum electricity demand..
Nice theory, but no. What wind turbine conspiracy theorist told you that? Because they're wrong.
Wind power is consistently higher in the UK in winter, and lower in summer:
You can see the trend over the last year here:
http://gridwatch.templar.co.uk/
But the trend has been found back to 1979 (the earliest they looked) and climate models indicate it will continue:
https://www.carbonbrief.org/uk-wind-power-can-help-meet-peak-winter-demand-study
We're currently in the summer portion, so wind is generally lower right now. Solar is doing well though.
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Not a conspiracy theorist but those ignorant buggers at the Civil Aviation Authority who insist I have to read meteorological textbooks written by professional liars and take exams where the answers are wrong. That's why planes keep getting lost and falling out of the sky - the wind gradient simply doesn't exist and the bloke in the control tower is just making it up.
Generated wind power is lower in summer because wind farms are paid not to produce electricity when demand is low. Gridwatch showed large peaks of wind power in October and November but a spectacular shortage in December, January and February, which was made up with huge peaks of gas consumption.
There must be something wrong with my solar panels. It's nearly midnight, and not even a microamp from them. Evan seems to have the same problem in Australia. Pleased to hear that yours are doing well.
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Not a conspiracy theorist...
Generated wind power is lower in summer because wind farms are paid not to produce electricity when demand is low.
Oh not conspiracy theorists, not conspiracies at all!
They only turn off the wind turbines, when the transmission lines saturate or wind power is within a couple of gigawatts of total demand. They don't just do it for fun!!!
Please point to the parts in summer where the wind farms are maxing out all or most of the demand, which days were these?:
http://gridwatch.templar.co.uk/
The UK record is 59.9% of demand supplied by wind turbines. What you're saying, that they're being turned off during summer is preposterous.
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There must be something wrong with my solar panels. It's nearly midnight, and not even a microamp from them. Evan seems to have the same problem in Australia.
When it's nearly midnight in the UK, it is midday here, and the solar panel inverter is usually humming along happily...
Now if only we could get a very long extension cord....
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The UK record is 59.9% of demand supplied by wind turbines.
And what, pray, was the demand? Total installed wind capacity is 15 GW so the demand at the time cannot have exceeded 25GW, which places it at midnight on a hot June date.
Fortunately we have about 30 GW of available fossil power to recharge all the electric cars.
And 59.9% is still some way short of the 100% that EoN advertise.
They don't just do it for fun!!!
That would be ridiculous. Everything in the industry is done for money. Why, for instance, is the UK government now offering to subsidise onshore wind farms when the best sites are already populated? Surely not to give taxpayers' money to Tory landowners? That would be a huge waste of effort when they could simply pay over the odds for medical supplies that never arrive.
Ah, hot June dates....takes me back to my youth...wonder where she is now?
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The UK has over 24 GW of wind power installed right now and this is still growing rapidly. The record was set in late August. I might be wrong but I think high winds are more common towards the end of summer.
Whether or not the 'best wind sites' are populated, there's still plenty of very good places to stick wind turbines.
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Gridwatch only reports 15 GW of metered windpower capacity and suggests there is another another 30% of unmetered local generation, but the reported demand figure is also limited to metered supply only. If there really is 25 GW capacity available and the wind blows adequately at night, the system should be able to provide 85% of minimum demand (because we need to keep the nuclear generators running) from wind.
"High winds" are not necessarily a Good Thing because they are associated with sharp gusts which can overstress the blades, so turbines are feathered to deliver a fairly constant power output over a wide range of geostrophic speeds and shut down quite sharply at the "maximum mean" to prevent damage.
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Gridwatch's website, while it tracks the power figures accurately, it is not kept fully up to date on things like that. Wikipedia is generally more current:
https://en.wikipedia.org/wiki/Wind_power_in_the_United_Kingdom
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Not a wise thing to suggest, since it paints an even gloomier picture of actual performance!
Gridwatch admits that it is only tracking metered power and there is another 30% of installed unmetered capacity, which comes pretty close to the Wikipedia total. However Eon only supplies metered power, so their claim of 100% renewables is obviously false.
Yesterday hit a peak of 13 GW of metered wind (the highest for a year) but that still only accounted for 50% of what went into the grid at the time.
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On Boxing Day 2020, a record 50.67% of power used in the United Kingdom was generated by wind power. However, it was not the highest amount of power ever generated by wind turbines; that came earlier in December 2020, when demand was higher than on Boxing Day and wind turbines supplied 40% of the power required by the National Grid (17.3 GW).[277][278] However, on 26 August 2020, wind contributed 59.9% of the grids electricity mix.[279]
But the uk requires 250gw of energy ON AVERAGE so overall 17.3 gw is laughable. We need to add 17gw of renewable yearly, that is not peak either, but constant.
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But the uk requires 250gw of energy ON AVERAGE so overall 17.3 gw is laughable. We need to add 17gw of renewable yearly, that is not peak either, but constant.
250 GW is power, not energy. The UK is not using 250 GW of power on average in any sense at all. What are you even trying to say?
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But the uk requires 250gw of energy ON AVERAGE so overall 17.3 gw is laughable. We need to add 17gw of renewable yearly, that is not peak either, but constant.
250 GW is power, not energy. The UK is not using 250 GW of power on average in any sense at all. What are you even trying to say?
Yes it is.
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Still no. The total energy usage of the UK in 2020 was 140 mtoe, which is 188.5 GW, average.
However, much of that is thermal energy which is not comparable with renewable energy. You typically have to divide by around 3 to get the equivalent in, electrical, renewable terms. So about 60GW. The UK grid averages about 30+ GW. So the amount of electrical power supplied needs to double.
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Still no. The total energy usage of the UK in 2020 was 140 mtoe, which is 188.5 GW, average.
However, much of that is thermal energy which is not comparable with renewable energy. You typically have to divide by around 3 to get the equivalent in, electrical, renewable terms. So about 60GW. The UK grid averages about 30+ GW. So the amount of electrical power supplied needs to double.
Still no, but mtoe gives a surprisingly close average number. Ah ha, I have you now! If you make statements like 50 percent of electricity in a specific day, to equate capacity with average energy output is fairly obvious. The 17gw of wind is not a day average either, just peak supply.
And why do renewable not need thermal energy? Is it because they are happy being cold or the toaster works at a lower temperature and the kettle boils as if at higher altitude.
https://www.britishgas.co.uk/home-services/boilers-and-heating/guides/boiler-efficiency.html#:~:text=A-rated%20boilers%20score%20over,boilers%20come%20in%20under%2070%25.
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However, much of that is thermal energy which is not comparable with renewable energy.
The argument diverges here.
I think we have put to rest the claim that EoN supplies me with 100% renewable electricity, so that is now a matter for the lawyers.
The broader question is what is going to replace oil and gas, and when. Unless we agree to freeze to death and stop makig things or going anywhere, we need to supply (not install, supply) the UK with about 188 GW on average, with peaks up to twice that number, whenever it is required, from somewhere.
Suggestions welcome - the Prime Minister's credibility depends on it!
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However, much of that is thermal energy which is not comparable with renewable energy.
The argument diverges here.
I think we have put to rest the claim that EoN supplies me with 100% renewable electricity, so that is now a matter for the lawyers.
The broader question is what is going to replace oil and gas, and when. Unless we agree to freeze to death and stop makig things or going anywhere, we need to supply (not install, supply) the UK with about 188 GW on average, with peaks up to twice that number, whenever it is required, from somewhere.
Suggestions welcome - the Prime Minister's credibility depends on it!
Sorry Alan for the distraction.
I would venture that eon is supplying you with hydro electric energy. That is how they can do it 24 hours a day 365 days a year.
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And why do renewable not need thermal energy?
It's because of electrification. Electric cars don't care about the Carnot cycle. The Carnot cycle needs thermal energy- and is incredibly wasteful, and is the best you can do with thermal energy. Heat pumps also do not need primary thermal energy, they need electrical energy. Sure, some things use direct resistive heating, kettles, induction heating etc. but they're largely low use items. The really big energy users, such as space heating, hot water, are going to be mostly handled with heat pumps.
Once you realise that, then you can see the gap is so much smaller than you thought it was. '250 GW' is just because of how horrendously inefficient we've been in the past.
And the answer is still, Is Eon a con: no, they're selling you net zero carbon electricity.
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Again, electric cars are not that brilliant, Internal combustion cars can be improved. Heat pumps are debatable to as whether they are more efficient. I have been and found a link for you. We need to improve the housing stock to this level, but that is a matter of at least a century.
https://www.logix.uk.com/beat-the-beast-from-the-east
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the Prime Minister's credibility depends on it!
He hasn't got any.
The broader question is what is going to replace oil and gas, and when.
You do realise that we have already replaced more than half of it, don't you?
https://renews.biz/67478/renewables-outstrip-fossil-fuels-in-uk-in-2020/#:~:text=Onshore%20and%20offshore%20wind%20provided%20more%20than%20half%20of%20the,and%20nuclear)%20generated%2059%25.&text=Renewables%20overall%20provided%2040.5%25%20in%20this%20period.
And that the 59% of our power that's low carbon as of 2020 was a 18% increase on the year before.
So, in fact, we are well on the way to doing what you keep parodying as impossible,
Are you going to get a kerosene lamp just so you will always be able to say that the UK isn't carbon neutral?
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An interesting source indeed.
Onshore and offshore wind provided more than half of the UK’s renewable power in 2020 by generating 24.2% of the UK’s electricity needs (13% from offshore wind and 11.2% from onshore wind).
Low carbon sources (renewables and nuclear) generated 59%.
"Statista" says: Electricity use in the United Kingdom has seen a significant decrease since the turn of the century. Demand peaked in 2005 at 357.2 TWh but had fallen to just 287.58 TWh by 2020.
That's just electricity, dear boy. Less than 30% of the UK's energy consumption is delivered as electricity. All the rest is fossil- fuelled.
Just to delve a bit deeper into your figures. 24% of electricity came from wind. All other renewables can only provide about 10 - 12%, so around 30% of the non-fossil power came from nuclear stations. Only one new nuke is being built and the old ones are beginning to creak a bit.
So my concern remains: how are we going to generate, store and use the other 60% of UK energy requirement when the oil and gas run out?
It's obviously possible, planned and fully funded, because it's inevitable and we have a world-beating private sector ready to take your money even if they have no expertise in power generation or any intention of actually delivering anything, and a competent and honorable government ready to give it to them. I'm simply asking about the physics and engineering (there can't be any chemistry, because that would make CO2).
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I would venture that eon is supplying you with hydro electric energy. That is how they can do it 24 hours a day 365 days a year.
Installed UK hydroelectric capacity is 1.5 GW - about 2% of average demand. And mostly supplied by Scottish Hydro, not EoN.
I used to fly an EoN glider, made by Elliotts of Newbury, that was indeed renewable, being mostly wood and canvas. EoN made wooden furniture until 1938 when they were commissioned to build troop-carrying gliders, and carried on into the 1950s with the very gentlemanly single-seat Olympia 463, incorporating the oxygen system, artificial horizon and a wheel from the Spitfire. But I don't think it is the same company.
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An interesting source indeed. Onshore and offshore wind provided more than half of the UK’s renewable power in 2020 by generating 24.2% of the UK’s electricity needs (13% from offshore wind and 11.2% from onshore wind).
Low carbon sources (renewables and nuclear) generated 59%.
"Statista" says: Electricity use in the United Kingdom has seen a significant decrease since the turn of the century. Demand peaked in 2005 at 357.2 TWh but had fallen to just 287.58 TWh by 2020.
That's just electricity, dear boy. Less than 30% of the UK's energy consumption is delivered as electricity. All the rest is fossil- fuelled.
less than 20 more like 15%
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www.edfenergy.com has an interesting table that claims EoN supplies 2.6% of UK non-carbon electricity. But EoN claim to supply 15% of to total demand, so clearly they can't be selling 100% renewable electricity at all.
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Why are you just repeating bullshit over and over again. It's not primary energy that's important, it's exergy:
https://en.wikipedia.org/wiki/Exergy
Which is the useful energy.
The way you're telling it, the fact that about 2/3 the primary energy mined for the UK is wasted is somehow a positive, irreplaceable thing, that must be replicated electrically?
Do you have any recent head injuries to explain this curious preoccupation?
Just to delve a bit deeper into your figures. 24% of electricity came from wind. All other renewables can only provide about 10 - 12%, so around 30% of the non-fossil power came from nuclear stations. Only one new nuke is being built and the old ones are beginning to creak a bit.
LOL, no, nuclear was 17.3% of net generation in the UK in 2020:
https://en.wikipedia.org/wiki/Electricity_sector_in_the_United_Kingdom
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No, about half of the "wasted" energy you speak of, is actually used as heat. Even that dreadful internal combustion engine in a car produces around 5 - 8 kW of cabin heat, which is why electric cars don't go as far in the winter. Steel and concrete production is essential if we are to build unnecessary railways at £1,000,000,000 a mile (yes, folks, £568,000 for every step of the way between London and Birmingham) and they require lots of heat.
Must go - some awful process is cooking my lunch.
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LOL, no, nuclear was 17.3% of net generation in the UK in 2020:
17.3 is actually more than 30% of 55. You should read more carefully before laughing.
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Even that dreadful internal combustion engine in a car produces around 5 - 8 kW of cabin heat,
And about 70 KW of waste heat that is blown out of the radiator.
Which is what makes them dreadful.
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No argument there. It's much the same end-to-end efficiency as burning fossil gas to make electricity, which is what EoN seems to be actually doing under the guise of "renewable".
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No, about half of the "wasted" energy you speak of, is actually used as heat. Even that dreadful internal combustion engine in a car produces around 5 - 8 kW of cabin heat, which is why electric cars don't go as far in the winter.
Pretty sure no normal car gives you 8 kW of cabin heat; and that's a shedload of wasted heat, particularly in summer.
And no, that's not why.
No argument there. It's much the same end-to-end efficiency as burning fossil gas to make electricity, which is what EoN seems to be actually doing under the guise of "renewable".
They're not, that would be fraud.
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Quote from: alancalverd on Yesterday at 15:26:01
No argument there. It's much the same end-to-end efficiency as burning fossil gas to make electricity, which is what EoN seems to be actually doing under the guise of "renewable".
They're not, that would be fraud.
My point precisely. It's in all of their TV adverts, and plainly untrue or at least misleading.
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Just picked this up from an EV chatroom. A little confused because they (Americans) actually mean BTU/hr, but the numbers are correct and just what I recall from my studies of light aircraft. .
A electric heater is rate at 3412 btus of heat per 1000 watts. If your cab
R-factor is low which could be rated at one R-factor for one single pane of
glass and one layer of 20 gage metal.
Lets say your cabin size has the area of a 5 foot cube, then 5 x 5 x 5 = 125
square foot (SF) of external wall space and the outside temperature is -40
degrees and you want to maintain 70 degree cab temperature which is a 110
degrees temperature difference (TD)
Therefore: Btus = SF x ((1 R factor)/1) x TD
125 x 1 u factor x 110
13,750 Btus
Watts = 13,740 Btus / 3412 btu per 1000 watts
Watts = 4029 watts or 4.029 kw
That's fine for maintaining cabin temperature but you need a bit more for a quick defrost. In an EV you'd do it with another temporary kW or so of wires in the windscreen, but where the heat is freely available from an ICE, you just increase the size of the heat exchanger to provide 5 kW or more to the circulating air. The 5 foot cube is pretty small and the calculation only applies to still air, so 8 kW is entirely believable for a medium to large car or SUV.
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just what I recall from my studies of light aircraft... .
...Where an outside temperature of minus 40 is plausible.
So what you are staying is that a typical car dumps twice as much heat into the cabin as would be needed if it was forty degrees below outside.
Why would you pick that figure?
And it doesn't really make a difference.
The engine is rated for something of the order of 100KW.
On a good day it's 25% efficient so 75KW is turned into heat.
You can use some to heat the passenger compartment- maybe 4KW on a cold day.
So about 71 KW is wasted.
That's still awful.
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I was once challenged in a Civil Service personnel review to respond to the allegation that I did not suffer fools gladly. I said "I didn't expect to meet any" and the subject was never raised again.
Just because your gas cooker is rated at 15 kW doesn't mean you have to use it all. When you design a car for mass production you tend to look at the cost of options. An 8 kW heat exchanger isn't much more expensive to make and install than a 5 kW one, will do the job better and quicker on a frosty morning, and will actually work in places like North America and Central Europe in winter, so why design one specially for gentlemen motorists with heated garages in Henley?
I don't think anyone here doubts the validity of the Carnot cycle. But some of us appreciate that it applies equally to power stations, which is why we don't like being lied to by or electricity supplier. And of course with an ambient of -40 degrees the engine would be rather more efficient anyway.
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I was once challenged in a Civil Service personnel review to respond to the allegation that I did not suffer fools gladly. I said "I didn't expect to meet any" and the subject was never raised again.
Just because your gas cooker is rated at 15 kW doesn't mean you have to use it all. When you design a car for mass production you tend to look at the cost of options. An 8 kW heat exchanger isn't much more expensive to make and install than a 5 kW one, will do the job better and quicker on a frosty morning, and will actually work in places like North America and Central Europe in winter, so why design one specially for gentlemen motorists with heated garages in Henley?
I don't think anyone here doubts the validity of the Carnot cycle. But some of us appreciate that it applies equally to power stations, which is why we don't like being lied to by or electricity supplier. And of course with an ambient of -40 degrees the engine would be rather more efficient anyway.
And would you like to discuss the piss poor efficiency of the engine?
At best, you are saying that not all of the 70% of wasted energy is wasted; maybe a few KW are used for something.
If you plan to talk about reuse of low grade heat then that's fine.
Consider a decent CHP station.
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Just because your gas cooker is rated at 15 kW doesn't mean you have to use it all.
Ironically, this only furthers my point, you simply can't. Gas cookers are only about 40% efficient, whereas electric cookers are more like 70%. Gas cookers, are great, if you want a space heater. That produces poisonous fumes. That have to be ventilated. So much win there. That hot air you just made, mostly goes straight out again. And it's mostly hot air. With poisonous carbon monoxide, nitrous oxide and sub PM2.5 particles. Mostly not hot pans.
An 8 kW heat exchanger isn't much more expensive to make and install than a 5 kW one, will do the job better and quicker on a frosty morning, and will actually work in places like North America and Central Europe in winter, so why design one specially for gentlemen motorists with heated garages in Henley?
Electric cars can have 8 kW defrosters too. They're not going to be on for long. Actually, electric cars tend not to need it because you can tell them to defrost themselves at a set time when you plan to drive. So the car is lovely and warm when you get in.
I don't think anyone here doubts the validity of the Carnot cycle. But some of us appreciate that it applies equally to power stations, which is why we don't like being lied to by or electricity supplier. And of course with an ambient of -40 degrees the engine would be rather more efficient anyway.
Still no. An electric car is still more efficient even at -40℉. And the electric motors themselves are more efficient at low temperatures anyway.
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And would you like to discuss the piss poor efficiency of the engine?
As I said, Sadi Carnot put that one to bed 200 years ago. But those unacquainted with thermodynamics might just refer to Wikipedia :
Modern passenger car diesel engines may have an effective efficiency of up to 43%, whilst engines in large diesel trucks, and buses can achieve peak efficiencies around 45%.
The energy efficiency of a conventional thermal power station is defined as saleable energy produced as a percent of the heating value of the fuel consumed. A simple cycle gas turbine achieves energy conversion efficiencies from 20 to 35%.
A bit sad, really, because I'd love to have an electric car, but for the foreseeable future it seems that it's going to burn more fossil fuel than the old diesel I already have, and I care about the planet. But that's the subject of another thread.
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And would you like to discuss the piss poor efficiency of the engine?
As I said, Sadi Carnot put that one to bed 200 years ago. But those unacquainted with thermodynamics might just refer to Wikipedia :
Given that adding cars to the electric requirement, I would like to discuss the piss poor efficiency of the electric car. Petrol 30 percent efficient.
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An electric car is still more efficient even at -40℉.
Sadly not. You use some of the battery energy to raise the battery temperature and reduce its internal impedance so it can deliver full rated power to the motors. It's a neat trick that we use to start aircraft on a cold day with a tiny battery (because battery weight is much more important in a plane) and is adopted in all current production electric cars. Difference is, of course, that the plane quickly recharges the battery and doesn't rely on it staying warm once the engine is turning.
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It's way off the subject, but out of interest I wondered how much power you need from a car heater to prevent ice building on a windscreen in a snow shower. Assuming you are driving at a sensible speed of about 10 m/s (22 mph) and the snow is falling at a "light shower" rate of 10 gram/second per square meter of ground, you actually need about 30 kW to keep a square meter of windscreen above freezing point. Once the inside drops below 10°C it will mist up, and of course a layer of ice will form inside if it drops below zero. The trick is that "defrost " mode doesn't deliver the warm air evenly over the screen but principally in the driver's immediate line of sight.
You can get away with less in a car because you can slow down and use windscreen wipers, but the deeply curved windshield of a small plane won't accommodate a wiper and you have to travel at around 50 m/s to stay airborne and make progress over the ground, which is why icing is such a problem in light aviation.
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Gas cookers are only about 40% efficient, whereas electric cookers are more like 70%.
Depends on how competently you use the heat. A gas cooker converts about 95% of the gas energy to heat. A resistive electrical element converts 100% of the electrical energy to heat, and an induction cooker transfers over 85% of the input power to a properly-designed pan.
What I have never understood is the rarity of electric kettles in American kitchens. All my US and Canadian friends and business associates boil water by putting a tin kettle on a radiant electric or gas ring. Can anyone explain? Could we save the planet by making 110 volt kettles compulsory?
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And would you like to discuss the piss poor efficiency of the engine?
As I said, Sadi Carnot put that one to bed 200 years ago. But those unacquainted with thermodynamics might just refer to Wikipedia :
Modern passenger car diesel engines may have an effective efficiency of up to 43%, whilst engines in large diesel trucks, and buses can achieve peak efficiencies around 45%.
The energy efficiency of a conventional thermal power station is defined as saleable energy produced as a percent of the heating value of the fuel consumed. A simple cycle gas turbine achieves energy conversion efficiencies from 20 to 35%.
A bit sad, really, because I'd love to have an electric car, but for the foreseeable future it seems that it's going to burn more fossil fuel than the old diesel I already have, and I care about the planet. But that's the subject of another thread.
The UK doesn't use single turbine cycles for gas generators, it uses CCGT, the output from the gas turbines goes through a steam engine, running on the waste heat. They can achieve about 55% efficiency which makes them cheap to run while being less polluting as well. That together with nuclear and the ever growing amount of renewable generation means that the electricity is much more efficiently generated and electric cars make enormous sense in the UK.
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And would you like to discuss the piss poor efficiency of the engine?
As I said, Sadi Carnot put that one to bed 200 years ago. But those unacquainted with thermodynamics might just refer to Wikipedia :
Modern passenger car diesel engines may have an effective efficiency of up to 43%, whilst engines in large diesel trucks, and buses can achieve peak efficiencies around 45%.
The energy efficiency of a conventional thermal power station is defined as saleable energy produced as a percent of the heating value of the fuel consumed. A simple cycle gas turbine achieves energy conversion efficiencies from 20 to 35%.
A bit sad, really, because I'd love to have an electric car, but for the foreseeable future it seems that it's going to burn more fossil fuel than the old diesel I already have, and I care about the planet. But that's the subject of another thread.
The UK doesn't use single turbine cycles for gas generators, it uses CCGT, the output from the gas turbines goes through a steam engine, running on the waste heat. They can achieve about 55% efficiency which makes them cheap to run while being less polluting as well. That together with nuclear and the ever growing amount of renewable generation means that the electricity is much more efficiently generated and electric cars make enormous sense in the UK.
Yes gas is more efficient but only to the tune of 45 perc ent. 70 percent efficient distribution of energy from power stations, electric cars are about 80 percent efficient.
https://www.fueleconomy.gov/feg/evtech.shtml
This puts it at 25 percent when an EV is powered from oil. Hydrogen is far better than that, plus we don't have to bother with constructing the battery.
https://theconversation.com/hydrogen-cars-wont-overtake-electric-vehicles-because-theyre-hampered-by-the-laws-of-science-139899
Given the average petrol car runs at 30 percent even in its inefficient form at present, it doesn't seem wise to burn gas and oil to generate elctric to power cars, far less the coal that will inevitably be consumed in future. Adding something like a hybrid with smart technology such asmay even push Internal combustion past the 50 maximum percent efficiency of the engine alone.
https://en.m.wikipedia.org/wiki/Thermoelectric_generator#:~:text=A%20thermoelectric%20generator%20(TEG)%2C,a%20form%20of%20thermoelectric%20effect).
Trouble is no one bothers.
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Adding something like a hybrid with smart technology such asmay even push Internal combustion past the 50 maximum percent efficiency of the engine alone.
Sadly, the performance of hybrids doesn't match that of conventional ICE vehicles. They are preferred in US cities because there are no emissions at low speeds and short distances, and pretty good as taxis where the regenerative braking and smooth acceleration are handy in heavy traffic, but they will be banned in the UK because for general motoring you are lugging a big battery around the country and in town you are lugging a petrol engine and tank, so your power to weight ratio and thus overall fuel efficiency is compromised compared with a pure electric or ICE vehicle..
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Adding something like a hybrid with smart technology such asmay even push Internal combustion past the 50 maximum percent efficiency of the engine alone.
Sadly, the performance of hybrids doesn't match that of conventional ICE vehicles. They are preferred in US cities because there are no emissions at low speeds and short distances, and pretty good as taxis where the regenerative braking and smooth acceleration are handy in heavy traffic, but they will be banned in the UK because for general motoring you are lugging a big battery around the country and in town you are lugging a petrol engine and tank, so your power to weight ratio and thus overall fuel efficiency is compromised compared with a pure electric or ICE vehicle..
They may have a small weight penalty, but the battery for a hybrid does not need to be massive, a lithium battery the size of the standard car battery should suffice. The electric motor may have a small penalty too, plus the other bits. There is much that can be improved on a standard car, but considering that the fuel savings are relativley so small, it's the need for motivation for change that's lacking. There is quite a lot that can be done. Yet rather than implementing this now, they are banning the I C E in a few decades.
https://www.greencarreports.com/news/1095725_not-just-turbocharging-exhaust-gases-can-generate-electricity-too#:~:text=As%20in%20a%20turbocharger%2C%20exhaust,a%20supercapacitor%20until%20it's%20needed.
https://en.m.wikipedia.org/wiki/Energy-efficient_driving
Pulse and glide has appealed to me for ages, how can it be possible for your car to slow down on a decent.
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Actually supercars are all hybrids these days, and they completely outperform traditional ICEs. Electric drive trains can max out grip to accelerate up to some high speed, like 80 mph and then the greater power of an internal combustion engine kicks in in parallel to take you up to several hundred miles per hour. But... the complexity and maintenance issues of having two drive trains in parallel should not be underestimated. Formula 1 motors are all hybrids too. Again, not simple.
But for normal driving when you rarely go past 80 or 90 or so, hybrids aren't usually really worth it. People that have a plug in hybrid usually migrate to full electric with their next vehicle.
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My very eco-conscious neighbor has an electric car for local journeys, but finds a bicycle quicker for her daily 4 mile office commute (Cambridge has bike lanes everywhere, so the roads are too narrow for a car to overtake a bus or tractor, and they keep digging up half the carriageway to make more bike lanes - not that cyclists use them!).
Going anywhere else requires careful thought: charge the car the night before for a 50 mile journey, or plan an hour's en route recharge somewhere that it's safe for a single woman to be in the middle of the night if the round trip exceeds 100 miles. So she rents an ordinary car on non-office days.
The electric car is great fun to drive, but I haven't seen it move for several months..
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That's presumably an original Nissan Leaf, with an aged battery, not a modern electric car. It's about the worst electric car out there with the smallest battery, and the worst charging system. Overgeneralising much?
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No, it's a 3-year-old BMWi3
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The following Statement would certainly be Off - Topic...
But, Why commute?
🚴🛴🏍️🚗🚜🚐🚁✈️🛩️🚀🛸
Nope!
Not against it...folks have the Freedom to move around without any specific reason or business, Sure!
👍
But after Covid19...i observe Alot of folks Working from Home.
Hence curious... can't most office jobs be taken care off just at home?
🏡
Obviously Not feasible for all sectors, but it is a possibility Right?
🤔
P.S. - May everyone's commute be only half as awful, as the job they are commuting to.
✌️
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EoN, electric cars, wind turbines, all a con. King coal is on its way back
https://www.bbc.co.uk/news/business-58469238
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All of these units of time vary as to their exact length, but most consist of at least millions of years, with eons lasting billions or hundreds of millions of years.Hydro power and biomass provide a large share. Wind and solar provide more than a quarter of renewable energy and are steadily increasing in importance; Solar energy now provides 6% of total renewable energy (up from 4% in 2014), while wind energy provides 21% (up from 18% in 2014). Renewables have increased from 7% to 11% of the total since 2008.
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As I write, hydro is providing 1.6%, wind 6.4%, biomass 3.3%, solar 1.8% of UK consumption.
Gas is running at 49%, coal at 1.5% and nuclear at 15% with around 10% "various imports" and, for as long as it lasts, 6% from pumped storage.
So more than half of our present demand is being met by fossil fuels, a significant chunk by outdated nuclear reactors, and frankly damn all from truly renewables. Not good for a warm summer evening with very few electric cars being charged. And well short of the advertised "100% renewable"!
Don't be fooled by "installed capacity". Renewables (apart from hydro) rarely deliver 25% of installed capacity.
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As I write, hydro is providing 1.6%, wind 6.4%, biomass 3.3%, solar 1.8% of UK consumption.
Gas is running at 49%, coal at 1.5% and nuclear at 15% with around 10% "various imports" and, for as long as it lasts, 6% from pumped storage.
So more than half of our present demand is being met by fossil fuels, a significant chunk by outdated nuclear reactors, and frankly damn all from truly renewables. Not good for a warm summer evening with very few electric cars being charged. And well short of the advertised "100% renewable"!
Don't be fooled by "installed capacity". Renewables (apart from hydro) rarely deliver 25% of installed capacity.
Hydro and solar have a problem that they do tend to take up land as well, how many acres for the uk demand of 40gw output?
The electric cars are beginning to show!
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You can forget hydro. Practically all the useable sites in Scotland are either already developed or too precious to flood, and the rest of the UK is too flat.
For solar panels, an average for the UK over a year is about 1 - 2 W/sq ft, so to meet 40 GW you need 20 - 40,000,000 000 square ft of panels, say 1,000,000 acres, about 2% of the total land area. That's only skimming the surface of the problem since you get no solar power at night, so you need at least 500 GWh of battery and 40 GW of inverter capacity to keep the grid running.
And of course if we get rid of domestic gas heating and fossil-fuelled cars, we will need about 4 times the current grid capacity. By the time we have moved to all-electric traction and industry we will have about 15% of the country covered in solar cells. That will have quite an ecological impact.
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You can forget hydro. Practically all the useable sites in Scotland are either already developed or too precious to flood, and the rest of the UK is too flat.
For solar panels, an average for the UK over a year is about 1 - 2 W/sq ft, so to meet 40 GW you need 20 - 40,000,000 000 square ft of panels, say 1,000,000 acres, about 2% of the total land area. That's only skimming the surface of the problem since you get no solar power at night, so you need at least 500 GWh of battery and 40 GW of inverter capacity to keep the grid running.
And of course if we get rid of domestic gas heating and fossil-fuelled cars, we will need about 4 times the current grid capacity. By the time we have moved to all-electric traction and industry we will have about 15% of the country covered in solar cells. That will have quite an ecological impact.
2 percent or 4000 sq km is that is for 1/10th of the uk energy usage. Solar farms have to account for shadow angle and the access paths and tracks to the panels, total land area should top out at roughly 50 percent. With 10 percent built on there should be just enough room for the national parks. [ Invalid Attachment ]
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Electricity is not essential. Food is. 90% of the UK is farmed for food, and it's not quite enough to sustain the human population.
The choice is obvious: reduce the population to a level that can travel around on solar electricity and eat insects. That's good for the economy.
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The choice is obvious: reduce the population to a level that can travel around on solar electricity
Fair enough, I'll get my bolt gun.
Even if no children where born in the UK for the next 20 years our population would still be over 50million, already they would be running out of fossil fuels. I do not think there is anything else for it but loads of nuclear power plants and population control.
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Both are essential. The scientific problem is that it takes at least 10 years to build a nuclear power station even after the bribes have been paid. The economic problem is that a declining population implies a shrinking economy and falling house prices - the Daily Mail won't like that.
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Both are essential. The scientific problem is that it takes at least 10 years to build a nuclear power station even after the bribes have been paid. The economic problem is that a declining population implies a shrinking economy and falling house prices - the Daily Mail won't like that.
"house prices" are supply and demand at present, with the pitiful state of some housing stocks supply will not be outstripping demand for at least a generation.
10 years is OK for a nuke plant, once we get building it should reduce. My only concern is the design, a good failsafe design is needed very badly, one that is scrutinised for renewability, waste generation and storage, safety etc. Fukushima is not something that we can risk. But really we had better bite the bullet, fossil fuels are only getting more expensive.
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🙄
C.1.2. does Not seem a bad thing atall.
Who knew a damn Virus would solve our biggest problems.
Ps - Death is Glorifying!
✌️
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You can forget hydro. Practically all the useable sites in Scotland are either already developed or too precious to flood, and the rest of the UK is too flat.
For solar panels, an average for the UK over a year is about 1 - 2 W/sq ft, so to meet 40 GW you need 20 - 40,000,000 000 square ft of panels, say 1,000,000 acres, about 2% of the total land area. That's only skimming the surface of the problem since you get no solar power at night, so you need at least 500 GWh of battery and 40 GW of inverter capacity to keep the grid running.
And of course if we get rid of domestic gas heating and fossil-fuelled cars, we will need about 4 times the current grid capacity. By the time we have moved to all-electric traction and industry we will have about 15% of the country covered in solar cells. That will have quite an ecological impact.
2 percent or 4000 sq km is that is for 1/10th of the uk energy usage.
You're falsely comparing secondary energy with primary energy. Secondary energy is far, FAR more useful. More importantly, it would be about 1/2 of the exergy (usable energy) of the UK. And we already have about a couple of percent of the UK covered with buildings. Sticking solar panels on a lot of them would be a big start. And we have other sources of power such as wind, much of it off-shore. So what's the big deal???
And this isn't remotely a worldwide representative figure, the UK is EXTREMELY heavily populated. Most countries would need a much smaller fraction of their land area.
Also this is a strawman- nobody is trying to power the UK off only solar power anyway. But if we did, so what anyway?? 2% is nothing. 70% of England is farmland for example. Why is 2% somehow magically an impossibly big number???
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You can forget hydro. Practically all the useable sites in Scotland are either already developed or too precious to flood, and the rest of the UK is too flat.
For solar panels, an average for the UK over a year is about 1 - 2 W/sq ft, so to meet 40 GW you need 20 - 40,000,000 000 square ft of panels, say 1,000,000 acres, about 2% of the total land area. That's only skimming the surface of the problem since you get no solar power at night, so you need at least 500 GWh of battery and 40 GW of inverter capacity to keep the grid running.
And of course if we get rid of domestic gas heating and fossil-fuelled cars, we will need about 4 times the current grid capacity. By the time we have moved to all-electric traction and industry we will have about 15% of the country covered in solar cells. That will have quite an ecological impact.
2 percent or 4000 sq km is that is for 1/10th of the uk energy usage.
You're falsely comparing secondary energy with primary energy. Secondary energy is far, FAR more useful. More importantly, it would be about 1/2 of the exergy (usable energy) of the UK. And we already have about a couple of percent of the UK covered with buildings. Sticking solar panels on a lot of them would be a big start. And we have other sources of power such as wind, much of it off-shore. So what's the big deal???
And this isn't remotely a worldwide representative figure, the UK is EXTREMELY heavily populated. Most countries would need a much smaller fraction of their land area.
Also this is a strawman- nobody is trying to power the UK off only solar power anyway. But if we did, so what anyway?? 2% is nothing. 70% of England is farmland for example. Why is 2% somehow magically an impossibly big number???
Non follow
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I think "science journalism" is an oxymoron, like "military intelligence".
Ouch! I actually regard myself as a reasonably good science journalist! I certainly put the facts front and centre and check them very carefully, and I think we do quite well on the communications front!
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Scientists who write for the meeja are one thing, journalists who write about science are often another!
It's very unpredictable: the most accurate reports of any of my work have been in the Sun and the Daily Mirror, and some of the most mickeymouse reportage I have read was in the New Scientist!
I was impressed some years ago by a Swedish radio interviewer who had clearly done her homework. I asked if I could hear the final edit. She said it would just be a "de-ummed" 10 minute slot at midday in a lightweight Swedish-language news and popular music program and "we always do the interview in English because people will only believe it if the scientists speak for themselves".
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Eon scored a good four stars out of five for bill accuracy and a respectable three stars out of five in three other categories in our survey. That's not bad, but customers of the highest-scoring brands achieved four stars or more
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Since I have never received an actual meter reading from EoN in the last 10 years, I wonder how they estimate accuracy?
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In 2020, E.ON launched a new brand called E.ON Next for homes and small businesses, which supplies 100% renewable electricity. New customers now start as E.ON Next by default, and all existing Npower and E.ON contracts will eventually be moved over to it.
This was the cheapest tariff we were quoted for on the E.ON Next website for someone using a “medium” amount of energy (2,900kWh of electricity and 12,000kWh of gas per year). It was also the cheapest quote among the three traditional big suppliers in our survey: British Gas, EDF Energy and E.ON.
The rates you’re charged for the energy you use are fixed for a year and you have to manage your account online. You must agree to have a smart meter fitted if you don’t have one already. There are no exit fees, either, so you are free to switch to another deal whenever you like. As well as 100% renewable electricity, all the gas you use is carbon offset with the Carbon Positive v3 tariff. E.ON will also plant five trees on your behalf, which will offset your carbon footprint even more. This deal is also fixed for a year, online only and with no exit fees, and you must agree to have a smart meter installed.
Different Tariffs by E.ON:
· Next Flex
This is a variable tariff, so the rates you’re charged for your electricity and gas could go up or down, and there’s no end date or any exit fees.
· Next 2 Year v4
Next 2 Year v4 is a two-year fixed deal with no exit fees. You must also agree to have a smart meter fitted to take out this tariff, which send your meter readings to your suppliers automatically and let you monitor your energy use and costs in real time.
· Next 1 Year v4
This is the one-year version of the deal above and has the same monthly cost. As with all of E.ON Next’s tariffs, it comes with 100% renewable electricity and no exit fees.