[grapesodaaaaa]

Clearly you have thought a lot about carbon reduction, so I have a question for you.

Is a plug in hybrid or EV less polluting if you don’t have rooftop solar?

edit: I think I know the general answer, but I’m splitting hairs comparing a replacement car for an ICE vehicle that I have.

[trapexit]

You don't need your own rooftop solar. You can time your charges for when power is cheap (i.e. renewables are highly represented in the grid mix). In many locations you can get an electricity tariff that changes by time of day, either fixed times of day or nearly real-time to track the current wholesale price.

Here in Scotland, we have an EV electricity tariff that give us low rates between 00:30 - 05:30 while the wind turbines spin and demand is low, and our plug-in hybrid is programmed to charge during those hours. (We also run the dishwasher, washing machine, and tumble dryer on time delay during those hours as much as possible)

With nearly all of our car trips being local, the ~25 mile electric range the plug-in hybrid is rarely exceeded. We fill the petrol tank maybe once every 3 or 4 months, or when we're on a road trip.

Pure EVs are harder to justify in the UK currently unless you do basically all of your charging at home, because with 20% VAT added to the price of electricity from public chargers, and too-low fuel taxes, the per-mile cost is similar to—or sometimes more expensive than—driving on petrol. It's shockingly bad public policy.

[rjh29]

Octopus Energy in the UK. Sometimes you can get paid to take power off the grid. Unfortunately batteries are too expensive to make really good use of it.

[Schiendelman]

The EV is by far the least polluting option. In a year or two of normal driving, even on a dirty grid, you generate less pollution than if you were burning fuel in the car.

Grids are getting lower carbon intensity every year, so it just gets better after that.

It's also not clear that rooftop solar is better than anything else, the carbon involved in getting it to you, installing it, the business that does the installation… It's not very efficient.