The National Institute of Advanced Industrial Science and Technology (AIST) announced on May 28, 2007 that it had succeeded in collaborating with City of Sapporo and other organizations to achieve a 65 percent reduction in the energy consumed by the circulating pump in the air-conditioning system of Sapporo City Hall by injecting a surfactant into the circulating air-conditioning water. Surfactants are compounds that reduce the surface tension of water. It is estimated that taking this measure can reduce annual expenditures by 630,000 yen (U.S.$5,122) while eliminating about 32 tons of CO2 emissions.

As technology for reducing the motive energy required to deliver the water that serves a heat medium for air-conditioning systems in buildings, injecting a surfactant reduces the friction between the water and the inner walls of pipes. Thus, the energy consumed by the pump that supplies water to air-conditioning units throughout the building is reduced, saving electricity.

In this experimental study, the demonstration test was conducted from late February till mid-May 2007 at Sapporo City Hall, which has 19 above-ground floors and two basement floors. The surfactant used was an approximately 0.5 percent concentration of LSP-01A (manufactured by the LSP Cooperative Society). Data were collected mainly on the stability of the system and its heating performance, and so far no problems have been found.

As the system uses almost the same circulating pipes for cooling and for heating, the Institute started another experiment in August 7, 2007 to verify that the surfactant used for heating is also effective in cooling.

http://www.aist.go.jp/index_en.html

Posted: 2007/09/27 05:18:38 PM
Japanese version

TAG Energy , Local government , Technology , University/Research institute