mead cohen berger shevtsova garfinkle michta grygiel blankenhorn
Uh Oh EVs
How a Green Cause Is Worsening China’s Smog Problem

Electric vehicles may be one of environmentalists’ favorite eco-options, but they aren’t helping China clear its smoggy skies. To the contrary, they’re actually part of the problem, as their expansion in recent years has raised¬†demand for coal-fired power plants and increased the air pollutants those plants produce. Reuters reports:

A series of studies by Tsinghua University, whose alumni includes the incumbent president, showed electric vehicles charged in China produce two to five times as much particulate matter and chemicals that contribute to smog versus petrol-engine cars. Hybrid vehicles fare little better.

“International experience shows that cleaning up the air doesn’t need to rely on electric vehicles,” said Los Angeles-based An Feng, director of the Innovation Center for Energy and Transportation. “Clean up the power plants.” [. . .]

Tsinghua’s studies call into question the wisdom of aggressively promoting vehicles which the university said could not be considered environmentally friendly for at least a decade in many areas of China unless grid reform accelerates.

Greens would have you believe that electric vehicles are by nature environmentally friendly, but that glosses over an important point: how the electricity used by those cars is produced. In China, coal is going to be the cheapest option more often than not, and while the recent effort to get more EVs on the road might save emissions at the tailpipe, it is increasing localized air pollutants and greenhouse gas emissions at coal-fired plants. According to this new research, these EVs actually have a net negative effect on Chinese air quality.

This serves as a timely reminder of the dangers of buying into green hype. Many of the policy prescriptions they’d have governments champion have unintended consequences or, as is the case here, don’t actually accomplish the environmental achievements that they claim. It’s not enough to incentivize electric vehicle purchases with tax breaks. To really make this a effective¬†policy, you need to green the power supply itself and make sure the grid can handle the new, cleaner energy sources. None of that is easy, and, especially, it’s not cheap, but embracing this approach halfway has put China in a position where new cars are actually making its deadly smog worse.

Features Icon
Features
show comments
  • Andrew Allison

    EVs are far, far worse for the environment than IC-powered vehicles. Quite apart from the pollution produced in generating the electricity consumed, the Laws of Thermodynamics show that every conversion (from fuel to steam to electricity to high voltage (for transmission), transmission, to low voltage to DC to chemical energy to DC to kinetic energy) involves losses. Compare this sorry chain to the fuel-to-kinetic energy which drives an IC engine. I’d be surprised if EVs are even half as efficient in converting fossil fuel into motion.

    • f1b0nacc1

      While your analysis is completely sound, the problem is that most of China’s electricity is produced by burning coal, and very dirty coal at that (in very dirty power plants, making it worse). Under those circumstances, even though it SHOULD be cleaner, I wouldn’t be shocked if it ended up being dirtier.
      TL; DR = More efficient if the same fuel was being burned at both levels, but here it is different fuel at each level

      • Andrew Allison

        Believe it or not, I did consider this, but decided for the sake of brevity not to get into the issue of the fuel used for generation. The knock against coal is that, in addition to producing CO2, it produces other devilish (sulpherous) by products which, bad as the are, are not greenhouse gases. Oil produces less, and NatGas even less of the by-products, but the combustion of them all produces CO2 (roughly 2.0:1.5:1.0). There is, of course, any easy way (nuclear) to make the generation of electricity clean. Good luck with that.

        • f1b0nacc1

          Frightening….we agree again!

          One minor point….the real problem with coal (the CO2 thing is silly and spurious) is heavy metals…

          • Andrew Allison

            This must stop!! [grin]

    • Pait

      The calculations you showed to me above would have electric cars as efficient as gasoline cars, so they contradict your statement here – I’m surprised you didn’t bother to correct it.

      Still, they underestimate the efficiency of electric cars significantly.

  • Pait

    Producing electricity in central plants is a lot more efficient than burning gasoline in an internal combustion engine. Thus the chances that electric cars actually pollute more than gasoline cars are rather small. It is moe likely that your post is in error.

    • Proud Skeptic

      Actually, with the direct burning at the source of gasoline, the gasoline powered cars are more efficient. Burning anything to make electricity is a multistep process, involving waste heat and all of the other by products a gasoline engine involves. The killer for electricity are the huge transmission losses that are incurred.
      Think about it…electric resistance heat in a home is almost 100% efficient but nobody uses it because it is the most expensive way to heat a home. The reason is the inefficiency of electrical generation and the losses over the grid. It is much cheaper to burn oil or gas at the site (your home) and heat that way.

      • Pait

        No, they are not. Internal combustion engines are very inefficient. Electricity transmission losses are significant but the higher efficiency of central power plants easily compensates that, which is one big reason we don’t generate electricity with small home generators.

        Heating is different because burning gas or oil at home for the purpose of generating heat is also 100% efficient. However burning fuel at home to generate electricity is not efficient – most of the chemical energy gets converted into heat. And burning fuel in a car is even less efficient.

        • Proud Skeptic

          Disagree. About 20% of the energy of the burning of gasoline gets to the wheels. In an EV, about 60% of the energy gets to the wheels. But that is only part of the story. Figure in 45% transmission losses to get the power from the power plant to the charger. The charger uses some energy. That puts EV’s at about 30%. The rest is easily accounted for in the converting of the energy from coal, gas, or nuclear to electricity.
          No big improvement in efficiency with EV’s. Break even at best.

          • Pait

            Transmission losses are closer to 10%. Electric motors are more than 90% efficient. Your numbers are not right.

          • Proud Skeptic

            Sorry…transmission losses are enormous.
            I’m done.

          • Pait

            It’s still not correct. Modern gas combined cycle generators are quite efficient. That is where the electricity would come from to satisfy the demand from electric cars. The improvement can be significant.

            I don’t understand exactly why you want to get the negative result, but changing from one wrong argument to another doesn’t make it more convincing.

    • CaliforniaStark

      http://cbsnews.com/news/think-electric-cars-are-truly-green-not-if-their-power-comes-from-coal/

      “The key is where the source of the electricity (for) all-electric cars. If it comes from coal, the electric cars produce 3.6 times the soot and smog deaths than those powered by gas, because of the pollution made in generating the electricity”

      Los Angeles often derives over 50% of its power from coal; from electricity generated in power plants in Utah, Arizona and New Mexico. Supposedly this will be phased out over the next decade. But the environmental trendy in LA who now charge their Teslas and Volts at night often are in effect driving coalmobiles.

      • Pait

        The issue about pollution is somewhat different. First, the air contaminants in a car are generated right where people are driving their cars; while power plants are most often farther from population centers. Also, there are many ways of controlling emissions that are economical in a central plant, while cars present more of a challenge.

        If you are concerned about greenhouse gases (CO2), then raw conversion efficiency is what matters most, of course.

        • CaliforniaStark

          Your original statement was “Thus the chances that electric cars actually pollute more than gasoline cars are rather small.” Then after reading a post with a scientific study contradicting this assertion, you state: “The issue about pollution is somewhat different” then call attention to the proximity of the pollution source. Am assuming you now are in agreement that electric vehicles powered by coal are more polluting than ones powered by gas, as the study in the CBS report states.

          As far as proximity, as a Southern Californian I hope people in Los Angeles take no satisfaction that by, in effect, exporting their pollution they have dirtied the air of the Grand Canyon, three other national parks, and the Navajo reservation.

          Your also say controlling emissions is more economical at a central plant, “while cars present more of a challenge.” The emissions from cars is determined by those of the central plant. In China four coal power plants near Beijing are being closed and replaced with natural gas plants; this will significantly reduce the emissions from electric vehicles in Beijing.

          • Pait

            One issue is efficiency; because electricity generation in a central plant is more efficient, electric cars will use less fuel. A 2nd is that the technology is more efficient, allowing regeneration from breaking losses for example. A 3rd is that pollution control at a central plant is more effective – that is what happens when replacing an old dirty plant by a newer one. A 4th point is that pollutants are generated farther from where people are, causing less harm.

            I see that there are a number of people commenting on this post that are heavily invested in the statement that electric cars are inefficient and pollute heavily. I may have mixed up one argument with the other so perhaps the answer in your thread was to the argument made by someone else in another thread. It doesn’t matter too much.

            Each one presents a different argument, and all of them seem to miss the point. If you want to turn the argument into a game of “gotcha”, there doesn’t seem to be any reason to proceed.

          • CaliforniaStark

            Thanks for the clarification. The efficiency discussion has been interesting to read. Do agree with you that replacing coal with a combined cycle gas plant as a electricity source gives an electric vehicle a more favorable emissions profile than a gas powered vehicle.

    • Andrew Allison

      You are mistaken. Electrical power generation is roughly 33% efficient, the IC engine about 25%. Transmission losses of around 11% make electricity less efficient than the IC engine, and that’s before the losses associated with conversion to/from chemical storage and the motor itself.

      • Pait

        A combined cycle electric power generator typically has efficiency of 50-60%. Electricity generation altogether has efficiency of 39% worldwide. A car engine typically has efficiency of 18-20%. The balance is still amply favorable to electric cars.

        Of course, other factors have to be considered, including where the pollution is generated – near or far from population centers.

© The American Interest LLC 2005-2016 About Us Masthead Submissions Advertise Customer Service