Little Rock, Ark. -- It looks much
like any other Entergy Arkansas, Inc. line truck – large, painted white with an
Entergy logo and a bucket stretched across the back.
But, on closer examination, this one
has something the others don’t: an electric motor. A long green stripe stretched
across the sides clearly labels the truck as a hybrid – a vehicle that has a
diesel engine and a battery-powered electric motor. Today three of the trucks,
which Entergy Arkansas leases, went into service in the Little Rock area.
The hybrid trucks offer several
distinct advantages over standard vehicles.
Fuel savings: Depending how they
are used, the hybrid trucks consume 20-30 percent less fuel.
Environmental benefit: Hybrids emit
less CO2, the most common greenhouse gas.
Safety advantage: At the work site,
the hybrids’ hydraulics are powered by batteries, rather than the truck’s
diesel engine. So they are much quieter, allowing for easier communications
between linemen on the ground and linemen working from the bucket on dangerous
energized power lines.
Entergy transportation planners
believe electric vehicles, in one form or another, are the way of the future.
Adding these hybrids to the fleet will give Entergy workers more opportunities
to learn how to maintain them.
In 2008 Entergy vehicles in Arkansas,
Mississippi, Louisiana, and Texas used 5,868,900 gallons of both gasoline and
diesel fuel at a total cost of $21,157,000. Of those, 1,200 were “medium-duty”
trucks (bucket trucks), and 3,000 were light-duty cars and pickups. The Entergy
Arkansas fleet has 312 medium-duty trucks, including the three new hybrids.
The three hybrid trucks added to the
fleet today average 6.09 miles per gallon. The standard version of the same
vehicle averages 4.96 miles per gallon. Assuming 20,000 miles a year, this will
save about 748 gallons per year per truck.
The company has leased ten new
hybrids, three of which will be used in the Little Rock area. The lease is
higher for a hybrid truck, but fuel costs will be lower. The amount of net
savings will depend on the price of diesel fuel in the future.
Three years ago Entergy Arkansas was
one of 14 utility companies to participate in a nationwide pilot of hybrid
service trucks. The results of that pilot validated the decision to invest in
more hybrids. The one truck used in the pilot in Arkansas is still in service
today. It has been as reliable as the conventional trucks.
While operating the vehicle is
similar to driving a standard-issue diesel bucket truck, a noticeable difference
comes after stopping at a job site. Normally, the noisy diesel engine powers the
boom that lifts the lineman to work on aerial power lines. In the hybrid, the
power comes from the quiet electric motor. It is during these idling times that
the hybrid vehicle is expected to cut down most on fuel consumption. Standard
diesel trucks burn one gallon of diesel fuel per hour when idling. The company
expects to save $2-3 per hour per hybrid truck by using electric motors for boom
It is not necessary to plug in the
hybrid to charge its batteries. They are charged by the diesel engine, as in a
normal vehicle, and they recapture kinetic energy when brakes are applied.
The battery system not only powers
the hydraulic unit during boom operations, it provides drive assistance until
the vehicle reaches about 20 m.p.h.
Entergy Arkansas, Inc. provides
electricity to 680,000 customers in 63 counties. Entergy Corporation is an
integrated energy company engaged primarily in electric power production and
retail distribution operations. Entergy owns and operates power plants with
approximately 30,000 megawatts of electric generating capacity, and it is the
second-largest nuclear generator in the United States. Entergy delivers
electricity to 2.7 million utility customers in Arkansas, Louisiana, Mississippi
and Texas. Entergy has annual revenues of more than $13 billion and
approximately 14,700 employees.