Once the steam enter the building, it goes into a radiator, turns into water and gives off heat in the process--the same type of reaction that causes third degree burns from steam. When the water vapor contracts into a more dense state--from gas to liquid--it gives off energy in the form of heat. Once the steam condenses to water after it has served its heating purpose, it is sent back to the plant through the same system of underground lines and tunnels.

Why Steam Still Matters

Hawkes says buying steam has advantages and disadvantages. "Nothing is a bargain," he says. "This system allows more space in [University] buildings and better use of space without having boiler rooms in each building." Hawkes also adds that steam heating is a lower maintenance system for the University.

At the same time, because the plant is not located directly on campus, the pipes lose some heat as the steam travels through the underground system. Engineers must also worry about the thermal expansion of underground pipes through junctions. "In 300 feet, [the pipes] may expand six to nine inches when they go from room temperature to steam at 400 degrees Fahrenheit," says Hawkes.

Once the heat reaches the pipes outside the building walls, control moves out of the hands of Engineering and Utilities into the domain of Facilities Maintenance Operations, and Hawkes can take a break.

"My responsibility is to bring the steam up to the wall of the building," says Hawkes.

Infiltrating the Buildings

Harvard's original steam source was the Boston Elevated Railway (now the Massachusetts Bay Transportation Authority Red Line) power house, located on Memorial Drive next to Weld Boat House. When the plant was razed to build the river houses, Harvard began to buy steam from the COM/Energy Blackstone Plant down the river.

When the plant moved down the river, Harvard had to build tunnels and lines to transport the steam. Weeks Bridge, for example, was not built for the purpose of a 'nice little foot-bridge,'" says Hawkes. "It was built to get the utilities across the river."

And despite the fact that one's room always seems overheated, Hawkes says a chilled water plant, located in the basement of the Science Center, does exist.

Unfortunately, "the chilled water plant is primarily not used for dormitories," he says. The cooling system is used mainly for libraries, laboratories and classrooms. In a similar method to steam distribution, the chilled water is produced at the plant at 42 to 44 degrees Fahrenheit and then pumped underground to about 65 buildings.

According to Hawkes, the plant works just like a refrigerator.

"Water is cooled down with a heat exchanger using freon as refrigerant," he says. "In the chiller, gas is compressed, and then as it expands, the cooling effect results."

The plant runs though the winter to cool laboratories or other locations with special needs.

"Treasure rooms, [for example], need cooling in winter to control humidity," Hawkes says.

Currently, the chilled water plant is expanding from 8,000 to 13,000 tonnage. To put this into perspective, Hawkes says a typical window air-conditioning unit in a bedroom is half a ton.

The Cost of It All

All this heating, cooling, electricity and water and sewage treatment costs the University approximately 25 million dollars each year. Heating alone amounts to about five to six million dollars, which comprises about half a percent of the University's 1.5-billion-dollar operating budget, according to Hawkes.