The innovative technological market keeps doing it—solving problems—for which we all benefit.
Pint-size hydro power on tap
By Michael Kanellos
Wed Oct 24 12:56:40 PDT 2007
REDWOOD CITY, Calif.--It's hamster-size hydroelectric power.
Rentricity, a start-up in New York City, has come up with a hydroelectric generator that lets municipal water facilities generate power. Pressurized water from the facility passes through a turbine, and the turbine produces water. The water subsequently comes out of your faucet.
The company doesn't like to use the term "hydroelectric power"--which conjures up images of large construction projects and regulatory tangles--but the principles are the same, Frank Zammataro, president of Rentricity, said during a meeting here at the Dow Jones Alternative Energy Innovations conference.
The system works because municipalities process millions of gallons of water a day and the water gets highly pressurized during the purification process. Some facilities process 9 million gallons of water a day and hold the water at 45 psi (pounds per square inch). If water came out of the faucet at that pressure, you'd have trouble washing your face without getting welts. Thus, water districts have to artificially bleed off the pressure.
But instead of doing that, the utility can make electricity. A single "Flow-to-Wire" micro-turbine generator from Rentricity can produce anywhere from 20 to 300 kilowatts of power, depending on the pressure and water flow. (A U.S. home solar system typically generates about 3 kilowatts.) Sensors and software from the company also monitor performance.
"It won't reduce the flow," Zammataro said. "We are taking off-the-shelf technology but configuring it in unusual ways."
