Boiler 2, which will be replaced this summer, is a "1950's vintage boiler" at "the end of its life," Packard said. A larger and more efficient boiler that is similar to the other three will be installed over the summer.
"It's a complicated project for sure," Packard said. "We're doing a project that will ensure that we can provide sufficient steam."
The construction project will also replace the original wooden roof of the power plant with a metal roof to make the building more resistant to fire, Packard said. The College is also implementing electrical redundancy at the plant, which ensures that the plant will function if a component fails.
The total cost for the project is $9.5 million, including $1.5 million for the new boiler.
The plant will close sometime in June to prepare the area for the new boiler, which will arrive in late July, Packard said. Once the area has been readied for the new boiler, the three existing boilers will be able to run, he added.
"We'll have a plant that's operational under most demands," Packard said. "The whole plant will be shut down when we're out for eight weeks."
The two temporary boilers will be able to meet the campus's demands for steam over the summer, Packard said.
The boilers produce steam at 450 pounds of pressure, which is then put through one of the plant's three turbine generators. Fifteen percent of the steam's energy is converted into electrical energy, supplying the College with roughly 40 percent of its electricity annually, Packard said. The steam comes out of the turbines in a saturated form at 20 pounds of pressure, and it is this change in pressure that creates electricity.
The rest of the campus's electricity is purchased from Granite State Electric, according to the Facilities Operations and Management web site.
The steam also supplies the College's heating and cooling, as it travels through a campus-wide tunnel system after leaving the turbines. The steam is then condensed to water and pumped back to the plant to be reheated. The College is able to reuse 90 percent of the steam, according to Packard.
Due to the connection between steam and electricity production, more electricity will be created on a cold winter morning when more heat, and thus more steam, is being used, Packard said.
"We only produce as much electricity as there is steam demand on campus," Packard said.
Because Boiler 2 produces steam at 160 pounds of pressure rather than 450 pounds, its steam cannot be put through the turbines to create electricity, according to Packard. Instead, the steam is run through a pressure reducing system to bring it down to 20 pounds so that it can be sent out to campus. The replacement boiler, however, will produce steam at 450 pounds of pressure, increasing the amount of electricity produced by the same amount of steam.
