Solar-powered airports? It could happen

— -- Jet contrails may be adding to global warming but on the ground, many airports are getting very green. During last week's Earth Day celebration air travelers could get free recycling tips at Seattle-Tacoma International Airport's energy fair, free tote bags at Denver International Airport, and free plantable postcards embedded with wildflowers at Boston's Logan Airport. And all during April, aka Earth Month, airports around the country trumpeted their successes with recycling, solid-waste reduction, hybrid vehicle adoption, air quality improvement programs, and other eco-friendly actions. One exciting trend: solar and wind power projects that may eventually allow some airports to operate off the grid. Here are just some of the airports generating their own juice.

• In 2007, San Francisco International Airport installed more than 2,800 solar panels on the rooftop of Terminal 3. Visible from the AirTrain that travels between terminals, the solar panels generate a small percentage of the airport's overall electrical needs, but enough to power all the daytime lighting needs in Terminal 3. Pleased with the success of this first foray into solar power, airport officials plan to integrate solar, and possibly wind, power into Terminal 2, which is currently being remodeled.

• In 2008, a highly visible "solar forest" sprouted up just outside the south baggage claim area at California's Long Beach Airport. The six solar "trees" are actually steel poles topped with photovoltaic (PV) arrays that measure about 9 feet by 9 feet each and shift and tilt throughout the day to track the sun.

While the forest is a test project that generates less than 10% of the airport's overall energy needs, airport spokesperson Sharon Diggs-Jackson says there are plenty of educational rewards being harvested. "We have information panels out there that explain the project and tell people about things they can do to save energy at home."

Next year, when the airport breaks ground for a new parking structure, Diggs-Jackson says solar technology will be an integral part of the project.