[FooHentai]

"This is the emissions index of an electric car, given the average amount of emissions generated by the production of the electricity that powers it."

Does this factor in locale? Because electricity generation in NZ is 80% renewable, and if we take the US generation ratio (I think something like 20% renewable), it paints a very wrong picture.

If it does take into account locale, kudos!

[hdodov]

We thought about that exact thing! However, we didn't have enough data to make this work. The numbers we display are averages. We'd love to make it more accurate once we have the resources!

[aurelwu]

getting even somewhat accurate values for that is a rather big problem, as you can't just take average emission values for a country as a base but rather need to look at the daily and weekly recharge distribution of different types of electric vehicles and then look at what the typical power generation structure is in those hours (which also varies seasonally). Its a huge project in itself and I think maybe you should just mention somewhere what values you use to calculate it.

[FooHentai]

Even so there's good, better, best on a spectrum, right? :)

Or is my '80% renewable' point naive? I think i get what you're saying, if I recharge during peak demand times, there's a chance nonrenewables are being used in higher proportions to fulfil my charge. Conversely if I charge during low-demand hours, the odds are higher that peak generation methods are not being employed.

But even more complicated than that, is the kind of renewables. NZ has a ton of hydro, and during certain times of the year they are drawn down for peak demand, so kinda ideal. Then again during times of drought, no can do and non-renewables may be the only thing that can meet demand.

If you're getting super fancy, NZ Transpower publishes live stats for the grid, including proportion of renewables in use at any one time! https://www.transpower.co.nz/power-system-live-data

[FooHentai]

Nice, thanks :)