Vehicle Electrification: More than Fuel Economy
By William G. Rankin
With
oil again approaching $70 a barrel and gasoline prices at the pump
over $3.00 per gallon, vehicle owners are feeling increased economic
pain and looking for relief. The solution offered by most vehicle
manufacturers is the incorporation of efficient electric motors
to displace conventional internal combustion engine (ICE) power.
Many companies, including UQM Technologies, Inc., are working on
vehicle electrification alternatives that provide a variety of benefits
to their customers.
Vehicle electrification may involve simply replacing inefficient
belt and gear driven under-the-hood auxiliaries (pumps, heating/air
conditioning, cooling fans, etc.) with efficient electric powered
ones. It can also combine electric propulsion with ICEs in various
parallel, series, and plug-in hybrid configurations to increase
efficiencies, or eliminate the ICE entirely by replacing it with
full electric propulsion, such as in a battery or fuel cell powered
vehicle. Generally, as vehicle power becomes more electric, fuel
efficiency improves and cost and complexity increases. With rising
fuel prices, vehicle makers are finding it much more feasible to
justify electrification, particularly when other benefits are considered.
Powering under-the-hood auxiliaries with electric motors has a number
of advantages. Auxiliaries can be relocated as needed because they
do not require proximity to an engine-driven belt or gear, allowing
for more flexible vehicle architectures and improved access for
service and maintenance. Operation is also independent of engine
speed, which allows variable speed and power modulation while improving
controllability and reliability. Importantly, powering auxiliaries
with electric motors takes a significant load off the engine and
reduces both fuel consumption and emissions. In order to power these
auxiliaries, the conventional inefficient alternator must be replaced
with a higher power, efficient generator, which can also provide
export power to run other on or off-board equipment. Under-the-hood
electrification is a key strategy of many diesel powered vehicle
makers to meet pending diesel emission mandates. 
Vehicle electrification offers different value propositions to different
vehicle makers and end users. When electric motors are used for
vehicle propulsion, their ability to instantly deliver high torque
results in exhilarating performance. Consider a 12,100-pound GVW
hybrid electric HMMWV with four 100 horsepower electric motors –
one driving each wheel – that does 0 to 50 mph in 7.5 seconds,
climbs a 60 percent grade, can be skid steered, is capable of operating
in stealth mode, and consumes 30 percent less fuel than a conventional
ICE powered HMMWV. The vehicle can also serve as a mobile powerplant,
eliminating the need to tow a generator and delivering sufficient
power to run a field hospital, command post, or 25 homes. This power
can also be used to operate electrically based weapon systems.
In agricultural tractors, electrification allows the replacement
of the inefficient and imprecise transfer of mechanical power through
a power-take-off shaft and hydraulics with electric power. With
electric propulsion, the tractor has improved performance, consumes
less fuel, and has sufficient electric power to operate implements
equipped with electric motors for planting seeds, applying chemicals,
and harvesting crops with precise control, resulting in less waste
and higher yields. The tractor becomes a mobile powerplant capable
of literally powering the entire farm.
Lawn tractors, like the one used to cut your lawn, can have similar
capabilities when electrified. Individual electric wheel motors
and electrically-driven cutter blades improve performance and consume
less fuel. And, like its agricultural big brother, the lawn tractor
is a mobile power generator capable of delivering electric power
to operate hand tools like saws, drills, weed trimmers, and chain
saws, and in fact an entire home’s electrical needs in case
of a power outage.
With these examples, you can only imagine the possibilities that
an electric grid-connected, mobile power plant that pulls into your
garage each night might bring to its owner.
William G. Rankin is
president and CEO of UQM Technologies (www.uqm.com), a recognized technology leader
in the development and manufacture of high performance, power dense,
and energy efficient electric motors, generators, and power electronic
controllers.
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