Geothermal Snow Melting System Nearing Practical Application

Many cities in snowbelt areas in Japan spend a large amount of money on snow control every winter, for methods such as pumping up and sprinkling groundwater over roads and warming the road surface with electrical heating cables. But a new snow melting system that uses geothermal heat has been attracting attention in recent years.

The system extracts geothermal heat from a depth of about 100 meters. The ground temperature at that depth is roughly the annual average temperature of the region, and stable throughout the year. In the geothermal snow melting system, a heat exchanger pipe is inserted in a hole drilled up to about 100 meters deep, and connected with iron heating pipes embedded just below the pavement surface. The system extracts heat from the earth by circulating antifreeze through the system. Since it harnesses natural energy to melt snow, its running costs are very low. One of the drawbacks of the system, however, is its higher construction cost.

The Snow Management and Construction Technology Research Center of Fukui Prefecture has made a great effort to reduce the construction cost and succeeded in cutting it by 75 percent. This has been realized by using the foundation pilings of buildings as a heat exchanger. In December 2003, the center tested the system on a bridge in Fukui City.

Using a technology that stores summertime solar heat for winter use, this system also cuts maintenance costs to one-twentieth of a conventional snow melting system that uses electric heating cables. Mr. Toshiatsu Kawahara, a researcher at the center, says that his center has embarked on a study to apply the new technology to the heating and cooling of buildings.




Posted: 2004/04/20 02:02:18 PM
Japanese version