Energy efficiency improvements are being implemented at airport facilities across the country because of a high return on investment. The centerpiece of the Portland International Jetport’s $75 million terminal expansion project was the installation of a geothermal heating and cooling system that reduces operating costs and emissions. A creative first in the airport industry, the $3 million project was able to make use of a $2.5 million Federal Aviation Administration (FAA) Voluntary Airport Low Emissions (VALE) grant. The system will maintain a constant temperature inside the terminal building by injecting heat into the ground during the summer and taking heat out of the ground during the winter. The system has 23 miles of high-density piping and 120 ground wells that reach as deep as 500 feet. The system moves more than 475 gallons of water per minute with a 125 horsepower pump. The new systems replace an oil-fired system and will save $160,000 in operating costs and prevent the emission of 1,000 tons of carbon per year.