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An interesting source indeed. QuoteOnshore 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: Quote 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.
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%.
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.
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:
Even that dreadful internal combustion engine in a car produces around 5 - 8 kW of cabin heat,
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.
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".
Quote from: alancalverd on Yesterday at 15:26:01No 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.
A electric heater is rate at 3412 btus of heat per 1000 watts. If your cabR-factor is low which could be rated at one R-factor for one single pane ofglass 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 = 125square foot (SF) of external wall space and the outside temperature is -40degrees and you want to maintain 70 degree cab temperature which is a 110degrees temperature difference (TD)Therefore: Btus = SF x ((1 R factor)/1) x TD125 x 1 u factor x 11013,750 BtusWatts = 13,740 Btus / 3412 btu per 1000 wattsWatts = 4029 watts or 4.029 kw
just what I recall from my studies of light aircraft... .
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.
Just because your gas cooker is rated at 15 kW doesn't mean you have to use it all.
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?
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%.
Quote from: Bored chemist on 25/05/2021 18:33:24And 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 :
An electric car is still more efficient even at -40℉.
Gas cookers are only about 40% efficient, whereas electric cookers are more like 70%.
Quote from: Bored chemist on 25/05/2021 18:33:24And 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 :QuoteModern 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%. QuoteThe 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.