Eric’s Apocalypse Averting Plan No. 1: Use electricity to power as many devices as is reasonably possible. Electricity, once you’ve got it, runs totally cleanly. No carbon output, less noise, fewer moving parts required, and therefore less maintenance needed. And the first machine that should go all electric would have to be our cars, right? Even though the Tesla is technically on the market, the cheapest way to use an electric motor in everyday driving is through the use of conventional hybrids or plug-in hybrids. Conventional hybrids use the gas motor and braking action to recharge, while plug-ins recharge by plugging into the wall at night. Plug-ins also have a small gas motor to extend their range.
But when I start spouting on about electricity and cars, I often get the same response: “But Eric, sure you eliminate tailpipe emissions, but you’re just adding to the pollution at the power plant. We’d have to burn even more nasty, dirty coal to power those snazzy machines.” It’s a major flaw in EAAP1, you know?
Thankfully the Electrical Power Research Institute and the Natural Resources Defense council also got tired of hearing that argument, so they did some research. The study (PDF) compares the CO2-per-mile of normal gas-powered cars, regular hybrids (like Priuses), and plug-in hybrids. The results were most gratifying: the plug-in hybrid produces far less greenhouse gas than conventional cars, even if all the electricity they slurp up at night is produced at a sooty old coal plant. The MIT magazine Technology Review used the study to generate the table I’ve included after the jump. It shows that conventional cars produce 452 grams of CO2/mile, about 28% more than plug-in hybrids, even if the plug-ins get all their electricity from coal-burning power plants.
In the United States, where much of our power comes from coal plants, the plug-in hybrids do a little worse than traditional hybrids. But with any kind of growth in clean energy, the plug-ins produce about half the carbon of the conventional hybrids. So another way I read these results is to give Prius owners yet another reason to pat themselves on the back. Under current technology, they’re driving the greenest cars around. Good on you, eh?
There are a couple of caveats here. The study doesn’t make it completely clear whether they take into account the full life cycle of both oil and electricity generation, like the cost of moving oil, building plants, mining for coal, and so forth. Given the remarkably clean rating given to nuclear power, I’m inclined to think they don’t. Possibly these effects are a wash, but I doubt it. Construction of a nuclear power plant produces a lot of greenhouse gas. Also, the study does not take into account the production of the vehicle. Electric vehicles of any sort do place a special strain on the environment because of all the materials needed to produce the batteries
I’d never heard of the Electrical Power Research Institute, so I decided to check ’em out. Mostly they’re a non-profit organization that does a lot of research and development for the electricity industry. I pulled their tax forms, and it seems they get two thirds of their $250 million operating budget from their members, most of whom are big power companies like San Diego Gas & Electric or Pacific Gas & Electric. Indeed, both of those companies are on the sponsor list for funding the report I’m writing about. I’m trusting this data in part because they have a good reputation for doing good science in the engineering community, and also because of the imprimatur of the NRDC.