Putting solar panels on the roof doesn't change emissions from driving an electric car

Powered by wind and sun, or not?

Earlier, I wrote about what happens when we put renewables on the grid and how complex it is.

Now we get to the question of whether putting solar panels on your roof makes your driving emissions free, or whether having a green generation company does the job. The answer may not please some people, because the panels don't significantly alter the emissions of your driving, while the power company does -- but it shouldn't matter because they are equally good things to do.

Part two can be found at Putting Solar On Your Roof Doesn't Make Your Electric Car Driving Green, But This Might


If it were true that "every mile I drive in my electric car causes a corresponding amount of renewable energy to be generated," then it would also be true that "every amount of renewable energy I add to the grid causes a corresponding amount of renewable energy to not be generated."

Just as there are no "solar electrons," there are also no "solar dollars." What does "My money goes only to solar and wind plants" even mean? Your money goes into a bank account where it gets mixed with a bunch of other people's money, right? A solar and wind plant is going to generate a certain amount of energy and get paid a certain price for it, and I don't see how how much you drive affects those amounts at all.

Essentially, "every mile I drive in my electric car causes a corresponding amount of renewable energy to be generated" (and "every amount of renewable energy I add to the grid causes a corresponding amount of renewable energy to not be generated") if the entire grid consisted solely of renewable energy.

Adding solar energy to the grid during times when renewable energy does not meet all energy demands makes the world greener. Earmarking your dollars for payment to renewable energy sources....well, I'm still curious what that means. What happens if the dollars earmarked for payment to renewable energy sources is more than (or less than) the payment renewable energy generators are entitled to? If it's less, presumably the remainder of the payment comes from payers who haven't earmarked their payments. If it's more...I don't know...it probably isn't more, unless the whole thing is a lie. (What would you want to happen in that case? I guess rolling blackouts would be a possibility.)

(Maybe if the demand for renewable energy exceeds the supply, the excess could be carried over into a future period when the supply exceeds the demand? Maybe that would induce supply. Maybe not, though, as that future supply might have happened naturally anyway.)

On that note, I guess if the demand for renewable energy exceeded supply, and a homeowner wanted to make the best impact for their solar panel installation, they would sell their solar power they generate solely to people who do not insist on only buying green energy, right?

A new piece of research has just come out of the University of Canterbury Engineering department that shows if New Zealand replaced 40% of the ICE vehicle fleet with EVs by 2040, this would only result in a 1.7% reduction in emissions considering a whole-of-life approach to EVs. If we upgrade the grid, then this changes to 6.7%. New Zealand already has about 78% renewable energy, so what we can learn from this is that overall, EVs are unlikely to offer the emissions reductions that everyone thinks they will provide us.

That's just a powerpoint -- would like to see the actual math if they have it. Surprised to not see better results for NZ. Note that "Get more people to use the bus instead" is wishful thinking. You can't wish people onto the bus. The bus has to offer competitive convenience to the car for that to happen.

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