Keeping Honda Motor Co. s facility in this western Ohio village cool during a heat wave without breaking the bank is as simple as freezing water. The Japanese automaker makes ice at night and then melts it during the day to cool the 1 million-square-foot complex of buildings, where vehicles are designed. Honda says the ice-chiller system saves on electricity costs by reducing power use during peak hours, while requiring less water than its old system.

Ice-chiller systems have been used in the past, but primarily by big operations such as convention centers, hospitals and universities rather than factories. "They got extremely popular in the early to mid- 90s. Manufacturers havent really gotten aboard with it so much," said Bob Smith, vice president of the Baltimore-based RMF Engineering Inc., which designs the systems. Vikki Michalski, spokeswoman for American Electric Power Co. of Columbus, Ohio, said ice-chiller systems are unusual among the utilitys manufacturing customers in Ohio. It can take businesses a long time to recover the costs of buying such a system and they take a lot of space, she said.

Hondas ice pit, which sits under the floor of the power plant that serves the complex, is 20 yards long, about 9 yards wide and about 8 feet deep. A spiders web of white pipes snake through the spotlessly clean power plant, and the only sound is the metallic hum of a condenser. Despite the ice-making system in its bowels, the plant is a comfortable 72 degrees. The ice-making begins about midnight, when two 450-ton chillers -- giant metal tanks that look like massive drug capsules -- kick on.

The chillers cool a salt water solution in the ice pit down to 22 degrees and circulate it through a series of coils. The water begins freezing on the coils and then at the surface. When the process is complete, about eight hours later, a 1-inch-thick sheet of ice has formed on the top of the pit. When workers arrive in the morning at the plant, located about 35 miles northwest of Columbus, the icy solution is used to chill the air that circulates through the buildings, cooling workers and heat-generating computer systems.

John Dirrig, an engineer who works at the facility, said he didnt notice any difference when Honda switched to the system a year ago. "You would never know from a user standpoint," he said. Honda officials declined to say how much the system cost. Allen Bickel, senior facilities engineer, said that while it costs more than conventional systems, he expects it to pay for itself in three years and last as many as 30 years.

Bickel said the idea came from a Honda research facility in Japan that was using a similar system. "It s a large pit, and it looks like a snowcone," Bickel said. Honda was honored Thursday by the United States Green Building Council, a group that advocates for energy efficient, environmentally friendly buildings. The award came in part because of the ice-chilling system. "Whats cool about it is that it s using ice as the coolant as opposed to any sort of Freon," said Elaine Barnes, executive director of the Cleveland Green Building Coalition, referring to the ozone-depleting gas often used in conventional air-conditioning systems. "It is a very clean and environmentally friendly source of air. Its a very efficient system."
(Por James Hannah, Environmental News Service, 19/07/2006)