Environmentally unfriendly electric cars?

[aleCcowaN]

This was published a couple of days ago in BBC's web.

The article is mainly based in this paper, published in the Journal of Industrial Ecology (editor and affiliations, linked there).

Both electric cars and papers talking badly about them are to be sceptically analysed, and this case seems to have a component of electric car "slandering" by coupling it to electricity generated using coal.

How much environmentally friendly are electric cars from a point of view of GHG generation?

 

[Bikewer]

Well, if you generate your electricity by burning fossil fuels, all you're effectively doing is "moving the pollution". Now that might not be a bad thing in congested cities... Places like Mexico City are evidently in a permanent state of exhaust-fume smog as are other major urban areas around the world.
However, for global warming... Not much help.

There are also problems dealing with the production and re-cycling of the battery components, of course.

 

[Dinwar]

Electric cars need to get their power somehow. If it's via burning fossil fuels, it's either going to be a wash or worse compared to burning gasoline. The benefit is that it's more easily controlled--if we ever find something to use CO2 for, we'll have a centralized supply (well several, anyway) rather than distributing it over the entire world.

If you generate electricity via solar panels, wind turbines, hydroelectric power, or something like that, you have to look at the GHGs emitted during construction, maintenance, and decommissioning. Not an easy thing to figure out.

Here's a breakdown of electricity generation in the USA. Coal is the dominant one, at 45%. So yeah, if you use an electric car your car likely runs on coal. Add the 23.4% for natural gas and 1% for petrolium, and 69% of electric cars run, essentially, on fossil fuels.

 

[Mikemcc]

Even assuming that all of the power was derived from coal, centralised coal burners could be fitted with CCS (if it ever gets past pilot plant scale operation and there aren't further complications). But the assumption that all the power comes from coal is bogus, it doesn't.

 

[Newtons Bit]

But the assumption that all the power comes from coal is bogus, it doesn't.

Who makes that assumption?

 

[WhatRoughBeast]

Who makes that assumption?

For purposes of comparison, both the linked article and the linked study do. For instance,

Electricity from coal, which is the most polluting way to generate power, drastically reduces the environmental advantage for EVs. Because China, for example, generates almost all its power from coal, life cycle analysis of EV cars in China shows they are far more polluting than conventional cars.

However, neither the paper or the study use that as the sole assumption, and both make it clear that for some areas EVs are better than petroleum-based vehicles (from a CO2 point of view). Norway, which gets most of it's electricity from hydo, falls into this category.

 

[aleCcowaN]

Well, the press article is just ... a press article . It's the "paper" which deserves a sceptical review, as it looks like a collection of disjointed analysis all pointing to a relative inadequacy of electric cars.

It starts from the very summary, where 12% of the text reads "EVs (electric vehicles) exhibit the potential for significant increases in human toxicity, freshwater eco-toxicity, freshwater eutrophication, and metal depletion impacts, largely emanating from the vehicle supply chain". Then, it's pointed the "limited" benefits of EVs, specially if a premature end of life is presumed (what translates into "if we fancy to waste resources like vehicles, electrical or not, EVs don't work so well avoiding increasing GHG", a surprising inference ). Of course, some value is to be assumed for EVs (not ECs). They assume 150,000 km as typical for EVs and support it with standard values for conventional cars (including Daimler Benz, whose Mercedes A class five doors is used). They quote, then ignore, lifetimes in specialized literature from 150,000 to 300,000 km. Surprisingly, not real value for EV is cited nor used (for Nissan Leaf, the electrical counterpart used, or as an average). According to the paper they also used a life cycle of 200,000 km that "exaggerates the GWP benefits of EVs to 27% to 29% relative to gasoline vehicles or 17% to 20% relative to diesel". C'mon! They wouldn't let anything to talk nice about EVs.

The fact is vehicles (not cars) include some 20% of the units running 50% of the mileage, that is, trucks, cab cars, police patrols, buses, travelling salespeople, etc. Life cycles of 300,000, 500,000 and 750,000 km are very common, if not the norm. And 50% of the mileage implies a 50% of the impact. Why is this not taken into account in the paper?

On the other hand, many countries, including mine, have or have had incentives to replace old cars. A typical plan in countries with heavy taxes on new car sales -like mine- is giving a rebate and a fiscal cheque of up to 4000 Euros if you sent your old vehicle to the crusher and the vehicle is less of 150,000 km. If such plans, used to stimulate economy during recessions, foster a shorter life cycle for vehicles, electrical or not, that is the environmental cost of such economical stimuli, and not the environmental cost of the vehicles themselves.

These were just a few of many objectionable elements in the "paper", the first ones, not even the worst ones. I hope you will also provide critical insights on it.

 

[cosmicaug]

This was published a couple of days ago in BBC's web.

The article is mainly based in this paper, published in the Journal of Industrial Ecology (editor and affiliations, linked there).

Both electric cars and papers talking badly about them are to be sceptically analysed, and this case seems to have a component of electric car "slandering" by coupling it to electricity generated using coal.

How much environmentally friendly are electric cars from a point of view of GHG generation?

I know I should RTFA (and maybe I will later) but is this taking into account efficiency? On the one hand, you have varying power transmission losses with anything electric but on the other hand internal combustion engines are incredibly inefficient as compared to electric motors.

 

[ehcks]

If your car is already electric, then you don't need to do anything when/if your country transfers its power systems from fossil fuels to renewable energy plants.

Even if it is slightly worse now, it will certainly be better in the future.

 

[Dr. Keith]

Electric cars need to get their power somehow. If it's via burning fossil fuels, it's either going to be a wash or worse compared to burning gasoline.

Only if you ignore the retail gasoline distribution system which is far less efficient than the distribution system for residential electricity.

 

[wardenclyffe]

I know I should RTFA (and maybe I will later) but is this taking into account efficiency? On the one hand, you have varying power transmission losses with anything electric but on the other hand internal combustion engines are incredibly inefficient as compared to electric motors.

There's also another way to look at efficiency. I would assume that power plants always try to run at peak efficiency in order to make the most money. Individual vehicle owners, while it is in their best interest, cannot be counted on to do so. For power plants, I'd think that their versions of catalytic converters are constantly inspected, whereas vehicles can pump out as much pollution as they want.

Ward

 

[Dr. Keith]

There's also another way to look at efficiency. I would assume that power plants always try to run at peak efficiency in order to make the most money.

Yes, they are much more able to run at higher efficeincies.

Individual vehicle owners, while it is in their best interest, cannot be counted on to do so.

This is not a matter of desire, it is a matter of what is possible. An internal combustion engine is most efficient (power/fuel) at wide open throttle (WOT). Cars are not designed to take advantage of that efficiency. They only rarely need that much power, so most IC engines in cars rarely will be used within their most efficient range. In fact, to get the best mileage from a car and maintain a comfortable ride, you would never use the engine in its most efficient state.

By contrast, a power plants tend to as efficiently as possible as often as possible.

For power plants, I'd think that their versions of catalytic converters are constantly inspected, whereas vehicles can pump out as much pollution as they want.

Most cars are inspected on an annual basis, so it is nto a complete free for all.

 

[jj]

It would seem that the argument that coal-powered electricity driving a car is "worse than gasoline"

This seems odd to me, most powerplants, coal or not, are rather more efficient than a gasoline engine operating at variable speed.

 

[wardenclyffe]

Most cars are inspected on an annual basis, so it is nto a complete free for all.

Is that true? In California (which I think would be pretty strict), I think it's only every other year. In other states, it might be even more lax. I drive an ancient diesel, so I'm exempt. Yes, I'm part of the problem.

Ward

 

[Soapy Sam]

It would seem that the argument that coal-powered electricity driving a car is "worse than gasoline"

This seems odd to me, most powerplants, coal or not, are rather more efficient than a gasoline engine operating at variable speed.

There are a lot of transmission losses though, jj.

 

[Dr. Keith]

Is that true? In California (which I think would be pretty strict), I think it's only every other year. In other states, it might be even more lax. I drive an ancient diesel, so I'm exempt. Yes, I'm part of the problem.

It is variable by location, but there are regular inspections for the majority of cars.

There are a lot of transmission losses though, jj.

As there are in the retail gasoline distribution system.

 

[Dymanic]

Is that true? In California (which I think would be pretty strict), I think it's only every other year.

And that only if you are within an "Air Quality Management District". Up in the Sierra foothills, where I live, smog inspection is required only on a change of title -- and even then there is an exemption if the new owner is a close family member.

 

[Dinwar]

Only if you ignore the retail gasoline distribution system which is far less efficient than the distribution system for residential electricity.

Fair enough. My point wasn't necessarily that electric cars aren't worth it--it was merely that we have to look beyond the cars themselves.

Scientific American did a recent article on the problems of tar sand that addresses these issues. I know it's not a scientific publication, but I was at the airport; what can you do?

And many cars are NOT inspected anually. Alabama and Ohio didn't require any checks, for example. Some states do, some don't.

This seems odd to me, most powerplants, coal or not, are rather more efficient than a gasoline engine operating at variable speed.

That's part of what I was trying to get at: intuition isn't going to help us much. We need someone to actually crunch the numbers.

 

[Dr. Keith]

Fair enough. My point wasn't necessarily that electric cars aren't worth it--it was merely that we have to look beyond the cars themselves.

Agreed. Some people just tend to focus on large smokestacks. You have to see the whole picture, the systems that support each vehicle from cradle to grave. And frankly, at this point it isn't a slam dunk and both are moving targets.

Scientific American did a recent article on the problems of tar sand that addresses these issues. I know it's not a scientific publication, but I was at the airport; what can you do?

You can do a lot worse, that is for sure!

And many cars are NOT inspected anually. Alabama and Ohio didn't require any checks, for example. Some states do, some don't.

I was not aware that entire states were free of inspections. Thanks. I do think the trend is towards more cars being inspected and I also think the trend is that cars are getting more efficient. Moving targets.

That's part of what I was trying to get at: intuition isn't going to help us much. We need someone to actually crunch the numbers.

And even then, the numbers are moving. Byt the time you finish your study there will be a new car available that is 20% more efficient, or has 20% more range, or uses less damaging battery tech. These things are in the pipeline, but the pipeline is moving quickly.

And as someone mentioned up thread: even if it is a wash now, it is easier to upgrade a set of power plants than it is to recall and upgrade a million cars. So, there may be reasons to favor electric cars because their pollution is centralized and more easily addressed.

 

[Nessie]

Lowering air pollution levels is the only definite advantage of electric cars IMO.