[swalsh]

Electric cars are filled with potential to have a decently large positive ecological impact, but as long as they're running on electricity generated by coal, they're just shifting the source of emissions.

However, even if we did move ALL cars off gas, the emissions problem is still very large, and solving it could reduce emissions by 65% [1]. This seems to be a 2 pronged approach, reduce car emissions, and reduce generic energy emissions. This alone won't solve the crisis, but it's a significant contribution.

https://www3.epa.gov/climatechange/ghgemissions/global.html

[ianai]

In a forum frequented by as many developers and engineers as this place I would expect a concept like decoupling to be better recognized. You switch the energy generation away from consumption. Your individual car is then out of the problem.

[mikeash]

The amount of electricity generated by coal is down significantly in the US. In 1997 it was almost 53%. Today it's around 33%. So that change is happening.

Based on my local grid, my car runs on roughly one third coal, one third natural gas, and one third nuclear. This seems pretty good, especially as it seems like the coal part will continue to decrease throughout the lifetime of the car.

Of course, with SolarCity joining Tesla, soon you'll be able to get both the car and the energy to run that car from the same company. Assuming your living situation allows for solar power, anyway.

[mjevans]

Even assuming coal, at least it is easier to install proper scrubbing in large fixed installations like generation plants.

I'm not sure about the tradeoff in efficiency between electricity transmission and generation in larger capacity: I'm just going to assume the cost and benefit in this set cancel out since we have more larger installations than local power generation.

[ianai]

Yep, bigger facilities usually have bigger economies of scale.

[zamalek]

The idea might be that you have your panels charge a battery by day, which feeds into your car by night. Use the same idea with "Tesla stations," with the price-per-mile barely more than the maintenance cost of the station - use a flywheel or maybe whatever the next wave of batteries is.

Only 14% of emissions come from transport (as per your reference) and, assuming an eventual complete transportation reform, that's still not enough. Master plan part (french N): shift/grow into the energy and industrial sectors. More announcements are coming, the only concern I have is that they come fast enough.

[spangry]

Ah, but one enhances the other. Solar (and wind) both suffer from the intermittency problem: both do not scale up or down to match demand peaks and troughs for electricity. Also the 'amount' of sun and wind varies geographically. So the two solutions are:

- Build roughly 6 sets of geographically distributed wind/solar farms (with 6 separate sets of transmission infrastructure) to handle base-load demand reliably. Expensive.

- Attach a whole bunch of batteries to the grid to smooth out demand. Also (currently) expensive.

I think Elon Musk's solution is to convince enough people to buy huge battery packs that they occasionally drive around, but mostly leave plugged in to the grid.

[kbenson]

> I think Elon Musk's solution is to convince enough people to buy huge battery packs that they occasionally drive around, but mostly leave plugged in to the grid.

Musk's plan is also to sell literal battery packs that attach to the wall, provide for expansion, and work in tandem. Which he is already doing.