Only 20 geothermal boreholes were drilled at the WestJet complex because a majority of the piping was embedded in the building’s structural piles.

19. Hybrid Geothermal Technology

The team at Stantec saved $800,000 in construction costs by embedding geothermal piping into the structural piles at the WestJet office complex in Calgary, Alb., rather than drilling boreholes adjacent to the building site, which is the standard approach. Regular geothermal installation would have required about 200 boreholes, each about four-inches in diameter and 300–350 feet deep, but incorporating geothermal piping into 73 of the building's 105 structural piles before concrete was poured required only 20 additional boreholes to be drilled, each about 350 feet deep. The geothermal system, in concert with the $100 million project's many other sustainable features (rainwater collection, daylighting, recycled materials), should help the property save $200,000 annually on energy costs and earn it a

LEED Gold rating.

20. Kinetic Road Plates Power Purchases

Kinetic road plates installed in a parking lot at the Sainsbury's store in Gloucester, England. Kinetic energy captured as vehicles drive over the plates is channeled back into the store. The plates can produce up to 30 kWh of electrical power every hour, enough to power the store's checkout machines. "Customers can now play a very active role in making their local shop greener, without extra effort or cost," says Alison Austin, Sainsbury's environment manager. The syst

em was invented by Peter Hughes, of Highway Energy Systems, based in Somerset, England.

Graduate student Shawn Shields checks server performance while Dr. Yogendra Joshi looks on at Georgia Tech’s simulated data center.

21. Cutting the Cooling Load of Data Centers by 15%

Researchers at the Georgia Institute of Technology, Atlanta, are using a 1,100-sf simulated data center to develop and evaluate new ways of controlling heat in commercial data centers, one of the fastest-growing building types in the country. The researchers, led by Professor Yogendra Joshi of the Woodruff School of Mechanical Engineering, have found ways to cut energy center cooling costs 15% by rearranging servers and space for optimal airflow patterns. Their simulated data center uses several different cooling systems, partitions to change room air volumes, sophisticated thermometers attached directly to a server's motherboard, and both real and simulated airflow sensors to measure the output of fans and other systems. The research is sponsored by the U.S. Office of Naval Research and the Consortium for Energy Efficient Thermal Management.