Comment on Nobody understands the point of hybrid cars
scrubbles@poptalk.scrubbles.tech 5 days ago
Damn, the average efficiency of an internal combustion engine is <30%, with the best hovering around 40%. That’s an insane waste energy, and does explain why they get so hot.
This is why the anti-EV propaganda is so bunk. Even if you plug an EV into a grid that is 100% dirty coal powered, you’re still more efficient than hauling around a gas engine that has such a low efficiency. Turns out, power plants don’t like wasting that much energy and do everything they can to squeeze as much power as they can out of it.
Then you add on that even the worst power districts in the US sit around 40% renewables and… yeah.
I have 3 counter-arguments for this “dirty coal” nonsense:
I think I found a misunderstanding.
It’s the renewables on the grid that have to make a difference. If you’re powering an electric car purely out of electricity generated with fossil fuels you’re effectively building a series hybrid with extra steps, with the combustion engine being outside of the vehicle. Or I guess you could also compare it to a diesel-electric locomotive with the generator outside the vehicle, which he also explained in the video would not be good for efficiency. And yes at the scale of power plants you can do some things more efficient, but it’s not actually that much as the efficiency is mostly limited by similar thermodynamic processes than that happen inside an engine. A typical coal power plant also has an efficiency of 30-40% (so effectively a mediocre coal plant is similar in efficiency to a very efficient engine). But when you get the energy from a power plant you still have distribution losses on the grid, conversion losses when charging the battery and again when discharging the battery, and the efficiency losses in the electric motor, while you do not have grid losses and charging/discharging losses and losses in an electric motor with a combination engine is directly driving the wheels.
That’s why it’s important to keep investing in renewables. You indeed don’t need a whole lot of renewables to offset the efficiency losses of the battery and distribution, but you do need at least some of it. And you also should not just look at the grid as a whole, but at how the additional load of charging the vehicle gets handled. If all renewables on the grid are operating at maximum capacity all the time, and there is a coal plant that is used to burn extra coal when extra capacity is needed, then any additional load can be considered to be running on pure coal power even if the grid contains many renewable sources. But if you live in a neighbourhood where there is a constant overproduction of solar power while the grid and can charge your car at times of overproduction, then you effectively charge your car with fully green energy even if the grid contains a lot of fossil fuel plants.
You can consider electric cars to be the infrastructure that enables the transport sector to become more green, but we do also need to actively increase energy generations via green sources to actually make use of that “infrastructure”. Though I guess there is also some good news: Powering an electric car from exclusively fossil fuel energy sources puts the efficiency of the full chain somewhere between regular cars and hybrids. So it should at least never be worse than driving a regular car. Worst case it’s just equivalent. But it does need investments in green energy sources as the demand on electricity increases to become significantly better.
Ooops@feddit.org 5 days ago
While that is true in general, combined coal power plants also only sit at about 50% on average, 65% with the most modern ones.
So burning stuff in a power plant, then adding some more loss in transfer, is not actually much better.
Which of course is not an argument against EVs but against coal and gas power plants. In the end they are still just glorified rather primitive steam machines.
scrubbles@poptalk.scrubbles.tech 5 days ago
Oh no doubt they’re horrible. Just that when looking through the lens of propaganda where a huge argument t against EVs is that it’s still hooked up to a per plant, that the pollution is not 1:1, that even the worst case power plant beats out an ICE vehicle.
But that requires critical thinking and nuance and Facebook commenters got no time for that.
JohnEdwa@sopuli.xyz 5 days ago
It’s much better when you take into account that to get gasoline, you have to refine crude oil first. That process alone uses electricity an EV could directly use instead - somewhere from 5-11kWh/gallon from what I can find, which is enough for roughly 15-33 EV miles - not to even mention the energy cost comparison for the whole extract - transport - refine - transport chain of gas.