[wolfekeeper]

In the context of this thread, for storing renewable energy, it's primarily a question of cost. If it costs £0.1 per kWh that is stored, then it's unlikely to be widely deployed as representing a large percentage of our power, whereas at ~£0.01 per kWh, it becomes more or less a no brainer.

I believe the quinones they're planning to use are believed to be relatively benign; they're chemically closer to photosynthesis quinones. The real nasty with previous versions was the hydrobromic acid, but they've replaced it with potassium hydroxide; which is clearly corrosive, but probably wouldn't form WWI-style gas attack if a premises caught fire.

[wolfekeeper]

In the context of the organic flow battery, taking Scottish Scientist's estimate of a requirement for 1400 GWh of storage, then we can calculate the cost for the batteries.

The estimate I saw before for the batteries was that the chemicals cost around $30/kWh of capacity. On top of that we would need tankage and pumps, and power converters. But for a first cut, let's just convert that nominatively to £30/kWh, as a start.

So we need 1400e9/1e3 = 1400 million kWh of storage, which at £30 per kWh = £42 billion for equipment that should last 20 years.

If we assume the money was borrowed for this at (say) 10% APR, I make that an average yearly cost of ~£70 per person. Which probably sounds like quite a lot. But this is deceptive.

Most of that is indirect charges, since much of the electricity is used in industry, and really overall the battery only adds a penny per kWh that is stored and then sold- and maybe about half of the power/energy would be used directly without storage. Additionally, wind power is a penny or so cheaper than nuclear, and wind power backed up with battery is flexible power- it's both baseload and peaking power; whereas nuclear power is really only baseload power, it gets more expensive when used to load follow, and it avoids any need for peaking plants.

[highvoltpower]

Nighttime energy demands is much lower than the day and we are wasting a great deal of energy from nuclear power plant and coal that’s difficult rapidly to power up. Wind power is cheapest source of renewable energy, but now a day’s challenge to deal with periodic movement of wind speed. Single wind farm will swing greatly, the variations in the total output from number of wind farms originally distributed in different wind systems.

[Robcat]

selected

100 since 1940 wow
Having spent 7 years of my life in nuclear I, m still alive but your 100 is missing some 5 noughts minimum
Or was that a joke?

[Robcat]

If you want really good reading matter, see if you can find a small book by Fred Hoyle in the 1960s/70s
It's called "Energy or Extinction"
It answers all your questions and put into KWHr all out uses of energy from fuel to food etc.
To the young. Fred Hoyle was a great informer.

Although times have changed,    guess the annual energy usage in KWHr of Americans, British and Indians on average before you read this book.
See how  wave power compares with wind turbines etc.

It's really essential reading.
Rob

[alancalverd]

we are wasting a great deal of energy from nuclear power plant and coal that’s difficult rapidly to power up

Very little is wasted - where and how would you dump it? The trick is to supply as much base load and predicted demand as possible from nuclear and big coal stations, using gas and small coal to supply short-term additional demand. In fact demand doesn't change abruptly as it is diversified among some 60,000,000 users. The problem arises when more than 20% of capacity is unreliable and generally unavailable when most needed - on the hottest and coldest days, when there is no wind.

[wolfekeeper]

Demand changes fairly quickly on the UK grid due to the wide availability of electric kettles. They actually have to have people in the grid control centre watching TV so they know when to kick in extra power.

Peak demand on the UK grid is actually in the winter, not the summer, and happens when wind is at its strongest.

See:

http://gridwatch.templar.co.uk/

Coal is being killed off now, even wind power often beats power production, the grid is mostly gas at the moment. Nuclear is chugging along, but I don't see it growing.

Worldwide, renewables are being installed and the net effect is that fossil plants are being retired; because renewables are cheaper.

Scottish scientist's plan of installing salt water pumped storage seems to be quite promising, particularly if there's a lot of solar in the grid, the electricity should be super cheap and reliable.

Solar panels are getting ridiculously cheap now; they're well under £0.5/W, and still getting cheaper. A 1kW panel produces about 900 kWh per year in the UK, and produces power more cheaply than the grid can, so a grid tied solar panel is a win for the consumer, and over the life of the panel ridiculously cheap.

[alancalverd]

Worth a careful look at the Gridwatch graphs. In recent weeks and months, demand has (as always) generally been highest when wind output was lowest. This is because UK winter weather is dominated by warm Atlantic lows, that bring high winds but mild temperatures, and cold Arctic highs that bring low temperatures and negligible wind speed.

The "electric kettle problem" hasn't really raised its head since 2 June 1953 when there was a hiatus in the BBC transmission of the Coronation and everyone had a cuppa and used the toilet - all the water pumps started at the same time. Thus warned, the CEGB managed to avoid significant power cuts after the 1966 World Cup Final but were caught unawares on 2 June 1979, a day of major national celebration.

[wolfekeeper]

Worth a careful look at the Gridwatch graphs. In recent weeks and months, demand has (as always) generally been highest when wind output was lowest. This is because UK winter weather is dominated by warm Atlantic lows, that bring high winds but mild temperatures, and cold Arctic highs that bring low temperatures and negligible wind speed.

A pretty story, but I am not seeing any such trend in the data.

The "electric kettle problem" hasn't really raised its head since 2 June 1953 when there was a hiatus in the BBC transmission of the Coronation and everyone had a cuppa and used the toilet - all the water pumps started at the same time. Thus warned, the CEGB managed to avoid significant power cuts after the 1966 World Cup Final but were caught unawares on 2 June 1979, a day of major national celebration.

Only because they watch this like a hawk and kick in Dinorwig when they need to; the idea that "In fact demand doesn't change abruptly as it is diversified among some 60,000,000 users." is clearly false.

[Scottish Scientist]

I've extended my modelling to include back-up generators and modelled some example working system configurations using scaled real world wind turbine generation data and demand data, from the UK grid during low wind conditions in September 2014.


Graph 8. Peak Demand (52,500 MW), Store – 0.6 days x peak demand (756 GWh), Wind – 2.7 x peak demand (141,700 MW), Back-up – 0.4 x peak demand ( 21,000 MW)

I've summarised the results in a table.

Table of wind, pumped-storage & back-up factors
The factors in the table are peak demand power multipliers. Each row triplet describes a possible system configuration for 24/7/52 reliable 100% renewable energy generation.



Using these results, I have written a web-page script on-line calculator -

Wind, storage and back-up system designer (my Scottish Scientist Wordpress blog post for documentation and discussion)

Wind, storage and back-up system designer (the actual calculator web-page which has to be hosted separately because it uses javascript which Wordpress, the blog host, don't allow).



Peak demand, wind and back-up power / energy usage and storage capacity calculator

For the specification and design of renewable energy electricity generation systems which successfully smooth intermittent wind generation to serve customer demand, 24 hours a day, 7 days a week and 52 weeks a year.

Adopting the recommendation derived from scientific computer modelling that the energy storage capacity be about 5 hours [see note] times the wind power capacity, the tables offer rows of previously successful modelled system configurations - row A, a configuration with no back-up power and rows B to G offering alternative ratios of wind power to back-up power. Columns consist of adjustable power and energy values in proportion to fixed multiplier factors.

The wind power generation Capacity Factor (C.F.) percentage can be adjusted too.

Note: I should caution against unrealistic "green energy" expectations following news reports of commercial engineering companies peddling - "largest ever" batteries which can store only 10 or less minutes times the wind or solar power capacity. Such relatively small energy stores are grossly insufficient to design a power-on-demand system where energy is sourced in the main from wind and solar power generators.
At best, expensive energy storage from batteries can cobble together wind and solar generators as bit-part generators in a grid system where most of the power must still come from conventional dispatchable generators, usually fired by fossil fuels. Therefore "largest ever batteries" or other battery sales in this context are a commercial marketing deception and a fraud driven by the profit motive which trick and lock-in grid managers into continuing fossil fuel dependence. Such batteries offer no "100% renewable energy solution" at reasonable cost. The established technologies to expect to be deployed for wind and solar energy storage are pumped-storage hydro and power to gas. So Elon Musk is every bit the enemy of renewable energy as Donald Trump is. At least Donald Trump is honest about supporting coal.

[alancalverd]

Long time  no see, my friend - good to see you are still at the helm!

Since our last joust on these pages my neighbour has bought a BMW electric car, Tesla have opened a showroom in the town centre, and HM Government has announced all sorts of drastic plans to have all-electric cars by whatever date, presumably in an effort to reduce the pollution of London air by trucks and buses. Said neighbour now uses the electric car to commute 4 miles to the gym instead of riding her bike to work, but always rents a petrol or diesel car if she has to drive more than 100 miles and come home the same day.

So here's the next problem. Driving around on a working day I note that peak times for motorway services are a broad surge around 0900, lunch stops 1230 - 1330, and absolute mayhem from 1700 to 1900. It's the last one that concerns me. Having charged your electric car overnight, you go to work, make a couple of trips to clients and suppliers, and then worry about getting home - sensible to top up en route, using the 500,000 fast chargers that have replaced the liquid fuel pumps (except for legacy cars, trucks, buses, tractors...). If every business motorist has an electric car, what is (a) the total additional demand  on the grid and (b) the likely evening peak demand?

I think we are agreed on power-to-gas, though I think that solution is a lot simpler than you do, but I think you will need to flood an awful lot of Scotland to satisfy England's future peak demand for pumped storage, and if the SNP has its way, who is going to invest in a renegade country that will sensibly sell its energy to the highest bidder (Germany)?

[Scottish Scientist]

Long time  no see, my friend - good to see you are still at the helm!

Hello Alan. It's the wee small hours so I'm half asleep at the wheel.

Since our last joust on these pages my neighbour has bought a BMW electric car, Tesla have opened a showroom in the town centre, and HM Government has announced all sorts of drastic plans to have all-electric cars by whatever date, presumably in an effort to reduce the pollution of London air by trucks and buses. Said neighbour now uses the electric car to commute 4 miles to the gym instead of riding her bike to work, but always rents a petrol or diesel car if she has to drive more than 100 miles and come home the same day.

Well that's why hydrogen fuel cell vehicles (H2FCVs) are the superior kind of electric vehicle - more energy, more power or longer range, higher specific power so faster acceleration and faster refuelling too.

So here's the next problem.

There's more? You've already signed Battery-only EVs death warrant and now you want to jump on its grave?

Driving around on a working day I note that peak times for motorway services are a broad surge around 0900, lunch stops 1230 - 1330, and absolute mayhem from 1700 to 1900.

Rush hours.

It's the last one that concerns me. Having charged your electric car overnight, you go to work, make a couple of trips to clients and suppliers, and then worry about getting home - sensible to top up en route, using the 500,000 fast chargers that have replaced the liquid fuel pumps (except for legacy cars, trucks, buses, tractors...). If every business motorist has an electric car, what is (a) the total additional demand  on the grid and (b) the likely evening peak demand?

Well can't the EVs charge up in the office car park? Without having done the sums I would guess that a standard 13 amp 230 V socket would do the job, one for each parking place.

I think we are agreed on power-to-gas, though I think that solution is a lot simpler than you do, but I think you will need to flood an awful lot of Scotland to satisfy England's future peak demand for pumped storage,

Or fill one part of Scotland with an awful lot of water, like 4 billion metres cubed.

STRATHDEARN PUMPED-STORAGE HYDRO SCHEME (up to 180 GW / 6,800 GWh)
World’s biggest-ever pumped-storage hydro-scheme, for Scotland?

Which I mentioned back in post 21, on: 15/04/2015.

Click for a larger image - https://scottishscientist.files.wordpress.com/2015/04/strathdearn_pumped-storage.jpg

The map shows how and where the biggest-ever pumped-storage hydro-scheme could be built – Strathdearn in the Scottish Highlands.

The scheme requires a massive dam about 300 metres high and 2,000 metres long to impound billions of metres-cubed of water in the upper glen of the River Findhorn. The surface elevation of the reservoir so impounded would be as much as 650 metres when full and the surface area would be as much as 40 square-kilometres.

There would need to be two pumping stations at different locations – one by the sea at Inverness which pumps sea-water uphill via a pressurised pipe to 350 metres of elevation to a water well head which feeds an unpressurised canal in which water flows to and from the other pumping station at the base of the dam which pumps water up into the reservoir impounded by the dam.

The potential energy which could be stored by such a scheme is colossal – thousands of Gigawatt-hours – a minimum of 100 GigaWatt-days, perhaps 200 GW-days or more.

This represents enough energy-storage capacity to serve all of Britain’s electrical grid storage needs for backing-up and balancing intermittent renewable-energy electricity generators, such as wind turbines and solar photovoltaic arrays for the foreseeable future.

The geography of Scotland is ideal for siting pumped-storage hydro schemes to serve a European energy network infrastructure, with benefits for Scots, Britons and Europeans alike.

Strathdearn (@ 6800GWh) would have the energy storage capacity of 700 Dinorwigs (@9.4GWh) or 50 times the biggest energy storage capacity in the world of San Luis in California (@126GWh).

and if the SNP has its way, who is going to invest in a renegade country that will sensibly sell its energy to the highest bidder (Germany)?

Well the UK currently buys electricity supplied via the interconnectors to France and the Netherlands who are actually better placed than Scotland is to offer their juice to Germany.

However Norway can easily snap up all the energy storage business from Germany, Denmark, the low countries, the Baltic States, Poland even.

Norway already has 80,000 GWh of conventional hydroelectric energy storage and this conventional hydroelectric power could be used in arbitrage trading.

Some more of Norway's conventional hydroelectric power could be converted to pumped-storage.

If that wasn't enough, Norway's fjords are ideal for sea-water pumped-storage schemes.

Plus Norway is closer to Germany and Denmark.

So whilst yes, it is possible for Scotland to supply the European continent it would have to do so through England or English waters and so Scotland is dependent on an ongoing cooperative relationship with England.

So it is from Scottish pumped-hydro that England, Wales and Ireland would get the better deal. It is Norway's energy storage that Germany will be bidding against England for. It is Norway who will have a crush of European customers who will push prices up. Scotland is a secure supplier for England.

[alancalverd]

"Filling up at the office" is an interesting idea. You can get about 3 kW from a 13A socket, and the average consumption of a small car is about 20 kW, so if your commute is 30 minutes and you arrive with an empty tank, you will have to stay in the office for  3 hours in order to drive home again. Just feasible. In wintertime, of course, you will have to stay an extra hour so you don't freeze on the way home. And if your commute was an hour, you would be better off moving house.

But the installed power capacity of the UK is currently around 1 kW per capita. A modern office may supply 2 kW per worker, and factories up to 5 kW. If everyone drives to work and back, without doing any useful journeys during the working  day, we will need to  double the power capacity of every workplace and install a whole load of weatherproof metered sockets in every car park. Who we? The employer, presumably. So now I have to spend another £500 capital per worker for the privilege of having them turn up at all, then charge them for the road fuel they use, deduct what they used on business once they had arrived at the office, faff about with differential tax rates....

Far better to skip the electric car nonsense and use all that free power to make liquid fuels from carbon dioxide and water. Now wouldn't it be nice if we could trap the CO2 at source - making petrol from exhaust fumes - there's a project for the next sixth-form science fair!

So whilst yes, it is possible for Scotland to supply the European continent it would have to do so through England or English waters and so Scotland is dependent on an ongoing cooperative relationship with England.

  Physics is one thing, politics is quite another.

[Scottish Scientist]

"Filling up at the office" is an interesting idea.

It was a suggestion in passing Alan in response to you raising the somewhat off-topic subject of electric cars and I can't be first person to have suggested that idea.

What I find particularly "interesting" and know a lot about is this topic "How can renewable energy farms provide 24-hour power?"

That's why I have posted this, in this topic.

I've extended my modelling to include back-up generators and modelled some example working system configurations using scaled real world wind turbine generation data and demand data, from the UK grid during low wind conditions in September 2014.


Graph 8. Peak Demand (52,500 MW), Store – 0.6 days x peak demand (756 GWh), Wind – 2.7 x peak demand (141,700 MW), Back-up – 0.4 x peak demand ( 21,000 MW)

I've summarised the results in a table.

Table of wind, pumped-storage & back-up factors
The factors in the table are peak demand power multipliers. Each row triplet describes a possible system configuration for 24/7/52 reliable 100% renewable energy generation.



Using these results, I have written a web-page script on-line calculator -

Wind, storage and back-up system designer (my Scottish Scientist Wordpress blog post for documentation and discussion)

Wind, storage and back-up system designer (the actual calculator web-page which has to be hosted separately because it uses javascript which Wordpress, the blog host, don't allow).



Peak demand, wind and back-up power / energy usage and storage capacity calculator

For the specification and design of renewable energy electricity generation systems which successfully smooth intermittent wind generation to serve customer demand, 24 hours a day, 7 days a week and 52 weeks a year.

Adopting the recommendation derived from scientific computer modelling that the energy storage capacity be about 5 hours [see note] times the wind power capacity, the tables offer rows of previously successful modelled system configurations - row A, a configuration with no back-up power and rows B to G offering alternative ratios of wind power to back-up power. Columns consist of adjustable power and energy values in proportion to fixed multiplier factors.

The wind power generation Capacity Factor (C.F.) percentage can be adjusted too.

Note: I should caution against unrealistic "green energy" expectations following news reports of commercial engineering companies peddling - "largest ever" batteries which can store only 10 or less minutes times the wind or solar power capacity. Such relatively small energy stores are grossly insufficient to design a power-on-demand system where energy is sourced in the main from wind and solar power generators.
At best, expensive energy storage from batteries can cobble together wind and solar generators as bit-part generators in a grid system where most of the power must still come from conventional dispatchable generators, usually fired by fossil fuels. Therefore "largest ever batteries" or other battery sales in this context are a commercial marketing deception and a fraud driven by the profit motive which trick and lock-in grid managers into continuing fossil fuel dependence. Such batteries offer no "100% renewable energy solution" at reasonable cost. The established technologies to expect to be deployed for wind and solar energy storage are pumped-storage hydro and power to gas. So Elon Musk is every bit the enemy of renewable energy as Donald Trump is. At least Donald Trump is honest about supporting coal.

So I would very much look forward to receiving an on-topic reply from anyone who finds any of that interesting.

 

[alancalverd]

This free symposium (including lunch) should be worth the trip

https://www.winton.phy.cam.ac.uk/energystorage.

Storage and distribution of energy is seen as the missing link between intermittent renewable energy and reliability of supply.  Current technologies that are being deployed have considerable headroom for improvements in performance, with the symposium speakers discussing some of the many new technologies that are being explored and how understanding the basic science of these can accelerate their development.

Though, like you, I think we already have the necessary technologies as long as people stop messing about with little batteries and concentrate on big infrastructures. My point throughout  the energy debate is that there is no point in developing electric transport systems or converting manufacturing industry from gas to electricity when we have perfectly good means of distributing and using liquid and gas fuels, and the possibility of manufacturing them with surplus electricity. "Start from where you are" is always a good motto.

[teragram]

Far better to skip the electric car nonsense and use all that free power to make liquid fuels from carbon dioxide and water....

"free power"
One of the points of this discussion is the projected shortfall of electric power when fossil fuels are phased out. Let's remember that we will have to derive ALL our energy from renewable electricity. By definition then the absolute best levels of efficiency are necessary. Surely this rules out using electricity to produce gas or liquid fuels at substantially less than 100% to then power vehicles (or anything else, except specialised processes). Battery vehicles are the most efficient of all the transport options.

[alancalverd]

The problem is that they aren't.

Whilst you might get 80-90% "revenue" efficiency from mains electricity to battery to motor, this only applies to brand new batteries, which generally fall to 50% overall within 3 - 4 years. The efficiency of production of mains electricity is unlikely to exceed 80% from source to consumer. So far, all electric vehicles have been heavier than their internal combustion equivalents, nobody has produced a battery that approaches the energy density of liquid fuels, and half of our energy consumption is for heating, not  motive power, which cannot be replaced without substantial capital investment, much of which is to pay the fuel cost of making new boilers and furnaces!

If we replace all oour consuming equipment with electrical equivalents, we will not only have to increase our renewable generation capacity by around 400%, but also build a huge new infrastructure for distributing it, whereas we already have all the requisite infrastructure for distributing liquid and gas fuels.

[Bored chemist]

"How can renewable energy farms provide 24-hour power?"
Diversity and a grid.

[teragram]

The problem is that they aren't. Whilst you might get 80-90% "revenue" efficiency from mains electricity to battery to motor, this only applies to brand new batteries, which generally fall to 50% overall within 3 - 4 years. The efficiency of production of mains electricity is unlikely to exceed 80% from source to consumer.

My EV now more than 3 1/2 years old, its battery recently tested during a dealers service and declared to be still 100%.

Petrol and diesel vehicles may reach 30% fuel efficiency in real life. I'm not sure of the overall efficiency of hydrogen production to fuel cell car, but I think that the fuel cell alone is around 80% efficiency, and also cannot absorb energy from regenerative braking without a battery (often fitted, I believe).

The transmission efficiency from generator to customer is around 90%. This may improve with more renewables, as generators although much smaller, will be in greater numbers, and widely distributed. As opposed to post privatisation when many power stations were demolished to capitalise on land sales, leaving fewer, distantly spaced large stations, resulting in longer transmission lines.

What method of powering vehicles gives more than 80-90%?

[wolfekeeper]

The problem is that they aren't.

Whilst you might get 80-90% "revenue" efficiency from mains electricity to battery to motor, this only applies to brand new batteries, which generally fall to 50% overall within 3 - 4 years.

That's true with laptops, but that's because the manufacturers want you to buy a new laptop every few years. Electric cars use almost the same type of batteries, but they do a few things differently. Number one is they recharge them more slowly- electric cars are mostly trickle charged at home. That greatly helps the battery life. Second thing is that they're mostly only charged to 80%. That roughly doubles the life of the battery. The third thing is that many cars have cooling systems for their batteries. That means that they don't get too hot during fast charges or enthusiastic driving- heat is a big enemy of Li-Ion batteries. And in hot climates they use slightly different chemistry that is more heat tolerant.

The upshot is that the batteries seem to be lasting a solid ten years or more.

The efficiency of production of mains electricity is unlikely to exceed 80% from source to consumer.

Yes, nearer 60% is more common I believe.

If we replace all oour consuming equipment with electrical equivalents, we will not only have to increase our renewable generation capacity by around 400%, but also build a huge new infrastructure for distributing it, whereas we already have all the requisite infrastructure for distributing liquid and gas fuels.

No, because electrical power is low entropy and so far more efficient than primary fossil power. But we don't have the choice to do business as usual. Fossil fuels are no longer viable. CO2 pollution is a huge problem now. In any case, the technologies are rapidly dropping in price and will soon overtake fossil technologies anyway in cost effectiveness.