An electric snowmobile competition
helps meet the need for a zero-emissions
workhorse in the Arctic.
by TRACY DAHL
SOLAR TODAY®
NOVEMBER/DECEMBER 2010
VOL. 24, NO. 9
Every year the SAE Clean Snowmobile Challenge kicks off with a lineup of the machines. Sixteen university teams competed in the 2009 competition, 17 in 2010.
The pioneering McGill EV snowmobile has evolved into a capable utility sled and was demonstrated as a workhorse at the Vancouver Winter Olympics. But the University of Wisconsin – Madison
team has won the Zero Emissions category of the Clean Snowmobile
Challenge three years running. They sent a team representative to
Summit Station twice: Ethan Brodsky in 2008 and Nick Radovec in
2009. UWM won the event again in 2010, but the team felt they had
gotten all they could out of testing in Greenland and sent runner-up
Scott Keefe, of Clarkson University.
Brodsky, now a Ph.D. electrical engineer developing new MRI tech-
niques, worked on UWM’s snowmobiles for six years, beginning in 2002.
For the eight-person BuckEV team, he coordinated battery and wiring
design and the interface with the control programmer. He spent three
days at Summit, traveling two days each way to get there. “The chief
design barrier remains range,” he says. “Gasoline still has a 100-to-1
advantage in energy density, but the electric sled pays for itself in a few
years in any remote location where you have to fly in gas. At Summit,
it even makes sense to charge from a diesel generator, because waste
heat from the generator is recovered for water- and space-heating so
it’s much more efficient than a gasoline snowmobile engine.”
“The biggest need for the snowmobile is in June and August, for
set-up and tear-down,” Brodsky said. It’s basically a mule, used to tow
sleds up to about 1,500 lb (680 kg) for 5 to 10 miles ( 8 to 16 km) at a
stretch. The electric motor is ideal for this kind of work, as it produces
maximum torque at 0 rpm.
Meet BuckEV, Three-Time ZE Champion
Tracy Dahl is a technical specialist in renewable energy
for CH2M Hill Polar Services.
location, far from any sources of industrial pollution, provides an international
research platform for atmospheric science, snow chemistry, ice core analysis
and other research, much of which bears on global climate change.
The station’s primary source of electrical power is a set of diesel-powered
generators. It creates a local pollution source that can skew research data,
depending on wind direction. Summit is resupplied mainly by ski-equipped
LC-130 aircraft, flown by the New York Air National Guard 109th Air
Wing. They too create very significant exhaust emissions that can affect
data. Heavy equipment and conventional snowmobiles are also contributors. One way to minimize data skewing has been to move the primary
sampling sites away from Summit proper, out to a satellite camp about a
ethaN brODsky
Jennie Thomas (foreground) and Jochen Stutz, from the University of California
– Los Angeles Department of Atmospheric and Oceanic Sciences, used the Buck
EV sled to transport a heavy and expensive set of optics.
BuckEV2 weighs 690 lb (313 kg), with a 356-volt battery packing
27. 6 amp-hours. The battery is composed of 1,296 lithium-ion cells,
from A123, with a market value of about $10,000 in 2010. The batteries drive a Delphi EV1 AC induction motor, producing peak 100 hp
(75 k W), or 50 hp ( 37 k W) under continuous load. The controller is an
Azure Dynamics DMOC 445LLC. To minimize noise and maintenance
requirements, EV2 uses a carbon-fiber reinforced Gates drive belt
between the motor and the track-drive paddle wheel.
