2/27/15, "Cold weather kills electric car range," mnn.com, Jim Motavalli
Image caption: "Carbon dioxide emissions per mile go up in colder climates, worsening the environmental equation. (Graphic: Environmental Science and Technology)"
"Range is a huge issue with EV owners, and for very good reasons.
The Volt has the gas engine in reserve, but 100 miles is the standard
top end for battery electrics. And that’s only under optimal conditions;
bad weather makes the range much worse.
A new study published in Environmental Science and Technology
(EST) looks at the range-and-weather equation, and reports, based on
driver testimony, that cold days (using the heater) or very hot ones
(air conditioning) can reduce range up to 40 percent. Remember that gas
cars generate their own electricity for accessories like that; in
electrics, everything drains the battery. Also, batteries simply aren’t
as efficient in extreme weather (especially if they lack pack heating
and/or cooling).
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And I’ve seen much the same in winter EV driving — the 100-mile car
becomes the 60-mile (at best) car. A Volt I drove during a New England
winter went 28 miles before switching to the gas engine, which isn’t bad
— Nissan Leaf and Mitsubishi i-MiEV cars I drove did much worse under
frigid conditions. One December, I got 34 miles from an i-MiEV
that’s rated at 62. Mitsubishi has warned i-MiEV drivers not to use the
heater because it will cut the range in half; a refreshed 2016 model
may improve that dilemma.
.
I like heat in the winter (and air conditioning in the summer), which is one reason my results are worse than average. Patrick Wang, a San Francisco Volt owner, told me that 40-degree weather reduced his range modestly to 34 miles, and he compensates by pre-warming the car while it’s plugged in at home, then setting the heater to low.
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I like heat in the winter (and air conditioning in the summer), which is one reason my results are worse than average. Patrick Wang, a San Francisco Volt owner, told me that 40-degree weather reduced his range modestly to 34 miles, and he compensates by pre-warming the car while it’s plugged in at home, then setting the heater to low.
EST’s research suggests that that in a city with a moderate
climate, such as San Francisco, the median range for a Nissan Leaf
battery electric is around 76 miles, and it’s above 70 miles more than
99 percent of the time. In a super-hot city like Phoenix, it can drop to
49 miles on the worst day of the year, while in super-cold Rochester,
Minnesota, a 36 percent range drop was observed. Even within a big state
like California, there can be energy-consumption-per-mile variations of
18 percent because of differences in weather.
Range (in all weather) is king, and that’s why the Tesla Model S’
265 miles is so prized. And it’s also why the Volt’s 2016 improvement is
so welcome....
Jeremy Michalek of Carnegie Mellon University, co-author of the EST
study, told me, “Climate is one extra factor that electric car buyers
should consider depending on where they live....
Michalek also points out that Californians’ environmental equation
is also bettered by the fact that the state gets most of its electricity
from clean sources. A Union of Concerned Scientists report found,
encouragingly, that 60
percent of the U.S. population lives in regions where, all factors
considered, the battery electrics emit fewer greenhouse gases than a Toyota Prius hybrid. Climate Central also investigated, concluding that electric cars are the best option for the climate in 16 states..
But these are moving targets. The electric grid is getting cleaner,
and as it does the EV’s environmental scorecard improves in most of the
country." via Junk Science, via Steven Goddard
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Linked in above article:
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2/24/15, "Carnegie Mellon Study Shows Electric Vehicle Range and Emissions Vary With Climate," cmu.edu, Tara Moore
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8/8/13, "A Roadmap to Climate-Friendly Cars: 2013," Climate Central
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