New Ground Air Units, Retrofits 737s With Winglets

Alaska Airlines announced Monday it recently began using mobile ground-based air units for cabin venting, cooling and heat on parked aircraft at nearly all its gates at Seattle-Tacoma International Airport. The airline also announced it has retrofitted all its 737s capable of using blended winglets. The two projects are the latest in a series of ongoing initiatives by the carrier to conserve fuel and reduce carbon emissions.

Since 2002, these efforts have reduced the amount of fuel Alaska Airlines uses to transport one passenger one mile by 17 percent. The accompanying reduction in carbon dioxide emissions is equivalent to taking 130,000 cars off the road for one year.

Of course, such measures don't simply offer environmental benefits... but economic ones as well. The diesel-powered preconditioned air units, along with ground-based electrical power, replace the use of an aircraft's onboard auxiliary power unit (APU), which runs on jet fuel. The ground-based units burn about 10 times less fuel than APUs, meaning the new units will significantly reduce costs and benefit the environment by lowering carbon emissions.

At Sea-Tac Airport, the use of preconditioned air units at 19 gates is expected to conserve more than 1.1 million gallons of fuel per year, saving the company $2.6 million annually based on the current pump price, said Kristin Fuson, an Alaska Airlines flight operations engineer and the project manager. Although the units burn diesel fuel, carbon dioxide emissions will be reduced by 24 million pounds a year because of dramatically less fuel burn, Fuson said.

Annual savings will more than double to 2.4 million gallons of fuel and $5.5 million once the units are in place at Alaska Airlines' other hubs in Anchorage, LAX, Portland and San Francisco later in the year.

Alaska Airlines had been moving toward using ground-based air units for about two years. Fuson noted the units make even better economic sense with oil prices hovering around $135 a barrel. The airline has purchased or leased 33 mobile air units for the five hub airports.

Even with the initial cost of $65,000 per unit, the machines pay for themselves in about 11/2 years, Fuson said. If the project is successful, more units will be purchased for other airports. Starting in September, some fixed units will be installed at all the hubs. The fixed units are powered by electricity from the airports and do not burn fuel or produce emissions.

Earlier this month, Alaska Airlines also completed retrofitting all its existing 737s capable of using blended winglets, matching new aircraft delivered to the airline. Winglets improve an aircraft's fuel efficiency and reduce greenhouse gas emissions by about 3 percent -- or some 100,000 gallons a year per aircraft.

Alaska Airlines has undertaken several other fuel-saving initiatives in the past year, including speeding up retirement of its MD-80s to fly only more-efficient 737s. As ANN reported, the airline's remaining seven MD-80s will be taken out of service August 25 instead of the end of December, as originally planned.

The carrier has also joined with other airlines in using only one engine when taxiing, and employing satellite-based en-route navigation. The carrier also switched to lighter-weight catering carts in 2006; that change alone has saved nearly 300,000 gallons of fuel annually, Alaska said.

FMI: www.alaskaair.com/