ERD50
Give me a museum and I'll fill it. (Picasso) Give me a forum ...
... Oh - is it a green vehicle? That's a bonus.
Unfortunately, no, it's not - or at least there are greener alternatives. Though if it is truly a high performance sports car you are after, it is probably greener than the competition in that arena. But that's not something that will affect the masses. More detail below...
Actually, that commonly accepted statement about the greener grid just doesn't hold up if you analyze it. I covered some of this in post #288,but this thread is getting long and thick, I'll just repeat it here:... There's a lot of misconceptions and misleading statements floating around. Frankly, they all have some basis in facts, so it's important to take them seriously and to provide real, accountable data to dis-spell any misconceptions. It is true that electric cars are more "green" in some areas of the country and world relative to others.
One advantage for electric cars is that even after you buy it, they get effectively "cleaner" when the source of energy gets "cleaner". Internal combustion engines are already unbelievably inefficient and they get even less efficient as they age.
As Texas Proud mentioned, infrastructure support isn't a problem for an EV fleet. Most people will charge at night, and the grid is 'idling' at that time. It could be a problem if lots of people wanted to charge at daytime on a peak A/C day, but night time has plenty of capability.
But it will take extra fuel to generate that electricity at night. It obviously won't come from solar, and hydro is being reserved at night to feed the daytime demand. Wind is stronger at night generally, so that can help a bit, but it isn't common to have an excess of wind power, so it will take more fuel. Which means a fleet of EVs would be mostly running on fossil fuel. And with a fleet, that demand would be pretty predictable, and most grids would rather keep their coal plants burning at a little higher rate than to keep their relatively expensive gas turbines running.
And yes, that means that an EV runs mostly on a combo of coal and natural gas. And though ICE automobile efficiency isn't great ( ~ 25%), EV efficiency doesn't look so good when you consider (rough numbers) ~ 40% efficiency at the power plant, 8% loss in transmission, 15% charging loss, and 10% motor loss. I think those are fairly generous, but .4⋅.92⋅.85⋅.9 ~28% overall efficiency, from fossil fuel to wheels. And even a little bit of coal mixed in with that will result in overall greater emissions from an EV than a decent efficiency ICE, and even worse compared to a high mpg hybrid.
To put it another way, say you are on a grid that has 30% renewables. And say they increase that over time to 40%. Now a 'silly' question - Why isn't it 50%? Well, obviously, because 40% is all they have. Since for most renewables (wind solar, maybe not biomass), the 'fuel' is free, the grid managers use it in preference over fuel they pay for. Following me?
OK, so now 10,000 people come home and set their EVs to charge overnight. That's an additional marginal increase in demand. And since the renewables have all been used, the only way to meet marginal demand is with fossil fuel. So you need to look at the mix of how a grid would respond to a marginal increase in demand.
Just like tax decisions, to evaluate the effect of selling some additional equities, you need to look at your marginal tax rate - averages don't matter.
From an environmental view, coal is so bad (particulates, Sox/acid-rain, etc), that even a small % mix on the grid makes an EV far worse than a decent hybrid.
On the positive side, I do think advances in hybrids will be what helps reduce the environmental impact of personal vehicles (and inter-city/delivery trucks). Hybrids have no range issues, and there are still advancements being made in ICE, and possibly micro-turbines (still too expensive and efficiency is not great). But a micro-turbine is one moving part, no oil (air bearings), so you are down to within one moving part of the simplicity of an EV. If they can perfect a 2-cycle free-piston engine, that only has a few moving parts. Although, even this is kind of a non-issue, modern ICE are so dang reliable, few people actually experience any serious problems during the life of the car anyhow. I don't put many miles on my cars, but I had my Volvo for 17 years, and drive-train-wise, replaced a thermostat. That was it, and not really needed, it was opening just a little slow and triggered the check-engine light, but I had an analog temperature gauge in that car, and it appeared normal, so was off just a hair. Our previous van, 12 years and no drive train failures. Some small amount of preventative maintenance, like spark plugs at 50,000 miles, coolant, maybe belts and annual or semi-annual oil changes - not really a big deal, though certainly nicer to not need those. And you can time that preventative maintenance with a tire rotation, so it's not an extra trip or anything.
-ERD50
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