...
However, I think your choice of allocating EV usage purely to the dirtiest part of the grid also introduces an unfair bias.
The same argument could be used to make a point against any incremental energy use - for example through increases in population. One could make the argument that children are "dirtier" energy users than adults because they came later, and therefore are incremental consumers of energy and are, by your logic, consuming the dirtier energy.
The reality is probably much more complicated than that. ...
Thanks, a reasoned response - finally! And I agree with your assessment, but not your conclusion.
Yes,
any added demand on the grid is going to come mainly from the 'dirty' portion. Like I said earlier:
Take a grid with 30% renewable. The renewable energy is all being used, there isn't any excess. So if I add demand, and I've already used all the renewable power, where does it come from? The only place it can come from - the non-renewable portion. How can it be otherwise?
Mathematically: 30% = 30/100. Increased demand (EV or any demand) by 10%, and the 30 is still 30, but you now have 30/110 ~ 27% renewable grid.
You treat renewable energy as a fixed quantity. Your hypothesis is that renewable energy is limited strictly by production capacity. ...
Because it is. There are only so many solar panels and wind turbines installed on any specific grid. Unless they are producing an excess which can't be used other ways, and
can be directed to EVs, (I've addressed the problems with this in
post #573), then that's it.
Sure, they can add renewables as time goes on, but it's the same story. Get to 40% renewables that are all utilized, plug in 1000 EVs and the added demand has to come from the non-renewable supply. Add 10% draw, and 40/100 becomes 40/110 ~ 36%.
HEY!!!! - Time for some POSITIVE news!!!!
While all this sounds so negative, I just realized there is a flip side that is very, very positive! Since marginal added draw is mostly from the 'dirty' supply, that also means that conservation is cutting mostly from that dirty supply as well! Conserving energy is a real win-win-win!
So if you conserve, I think you can 'brag' that you cleaned up the grid, and you don't have to base your conservation numbers on 'averages'! Works both ways, right?
.. You earlier "pooh-poohed" the notion of taking an average of all sources and allocating it to EV users, but I have to say that to me that's a more sensible metric than arbitrarily picking the dirtiest source. ...
It wasn't arbitrary. I gave the reasons, and I do think they are sound. Why do you say arbitrary? While I may have said ' the dirtiest source' as shorthand, a more accurate mouthful would be to say 'the non-renewable portion of the grid'. Which is probably some blend of coal, NG, etc. But not all that non-renewable power would come from the dirtiest of the dirty (if that is what you thought I was saying) - it would be a blend of the 'dirty'.
I'd be interested in the source data for your chart so that I could do an analysis using different allocations of energy.
Which chart?
-ERD50