Cold truths about electric cars' cold-weather shortcomings
By Charles Lane
Friday, January 28, 2011
Count me among the many thousands of Washington area residents who spent Wednesday night stuck in traffic as a snowstorm sowed chaos all around us. Being car-bound in sub-freezing weather for six hours can make a guy think. I counted my blessings. The situation could have been worse, I realized: My fellow commuters and I could have been trying to make it home in electric cars, like the ones President Obama is constantly promoting, most recently in his State of the Union address.
Cold truths about electric cars' cold-weather shortcomings
It is a basic fact of physical science that batteries run down more quickly in cold weather than they do in warm weather, and the batteries employed by vehicles such as the Nissan Leaf or the Chevy Volt are no exception.
The exact loss of power these cars would suffer is a matter of debate, partly because no one has much real-world experience to draw on. But there would be some loss. Running the heater to stay warm, or the car radio to stay informed, would drain the battery further.
Here's how thecarelectric.com, a pro-electric Web site, candidly summarized the matter:
"All batteries deliver their power via a chemical reaction inside the battery that releases electrons. When the temperature drops the chemical reactions happen more slowly and the battery cannot produce the same current that it can at room temperature. A change of ten degrees can sap 50% of a battery's output. In some situations the chemical reactions will happen so slowly and give so little power that the battery will appear to be dead when in fact if it is warmed up it will go right back to normal output. . . .
"In a car where all power is supplied by a battery pack you can see where this would be a problem. The batteries don't produce as much power so the car has less power. The batteries also have to work harder so the effective range of the car is also significantly reduced. Charge time will also be longer. Cold has a negative impact on all aspects of battery operation."
"Alongside the negative impact on the batteries cold also has a negative impact on the driver as well. Drivers need to be warm to operate the vehicle effectively so on top of the reduced range and power of the batteries just from the temperature they also must operate the car heater to keep you warm. This will further reduce the range of the car.
"If you live in an area where the winters get extremely cold an all-electric vehicle will have to be garaged and equipped with some kind of plug-in battery warmer for it to be effective in the coldest months of the year. Keep these thoughts in mind if you're planning an electric car purchase; we don't want you finding out the range of your car has been halved when it's five below zero and you're fifteen miles from home."
To be sure, gas-powered cars are hardly invulnerable. Plenty of motorists ran out of fuel in Wednesday night's mega-jam. But my hunch is that electrics would faced similar problems or worse. And many electric-car drivers who did manage to limp home Wednesday would have been out of options the next day: You can't recharge if you don't have electricity, and hundreds of thousands of customers were blacked out Thursday from the snow. The Post reports that this will be the case for many of them for days.
Carmakers say they are on top of these issues. General Motors has tested the Volt's battery in cold conditions and says it includes a margin of reserve power for such weather. Indeed, the Volt comes equipped with a backup internal combustion engine, so you need never fear, as long as the tank is full of premium gas (the only kind a Volt can use). Of course, burning gas rather defeats the "green" purpose of the $41,000 (before federal tax rebate) four-seat car. But at least you won't die of exposure on the road.
As for the Leaf, which touts a 100-mile range under optimum conditions (i.e., mild weather and no big hills like the ones I had to negotiate on 16th Street), Nissan is designing a "cold weather package" of options. But neither the cost nor the availability date has been announced.
Now, if the cars were cheaper than gas-powered cars of equal performance, these cold-weather risks might be acceptable. But electrics are substantially more expensive than cars of greater capability - and will be for years to come. Frankly, I don't know why anyone would consider buying one - especially if he or she lives north of the Mason-Dixon Line.
In his address Tuesday, the president reiterated his goal of putting 1 million plug-in hybrids and all-electrics on the road by 2015 and insisted that Congress spend hundreds of millions of additional dollars to achieve it. At present, fewer than 5,000 electrics are out there, so auto companies would have to make and sell about a quarter of a million vehicles annually between now and 2015 to meet his target.
Even with substantial government subsidies, I doubt the president will get there. Michael Omotoso of J.D. Power and Associates - a consulting firm that, unlike the Obama Energy Department, has spent a lot of time asking consumers what they actually want - told me the number could reach 750,000 by 2015, and 1.1 million by 2020 if all goes well.
But the million-car goal is meaningless: It would represent 0.4 percent of the U.S. automotive fleet, yielding no substantial reduction in carbon emissions or U.S. dependence on foreign oil for the government's multibillion-dollar investment. Alternative policies, such as a modest increase in the gas tax or support for more efficient internal combustion engines, would do more to accomplish the administration's legitimate goals faster and at lower cost.
Call me a curmudgeon, but I think J.D. Power is optimistic. This subsidized market niche is just one well-publicized malfunction away from disaster. Perhaps a Volt battery will overheat and burst into flames, as some computer batteries have been known to do. Or maybe a Leaf driver will suffer frostbite while stuck in the next blizzard. Let's just hope one of his neighbors pulls over to help him out.
The writer is a member of the editorial page staff. His e-mail address is firstname.lastname@example.org.
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