MIT has launched a two-year project that will replace the Institute's decades-old power plant with a state-of-the-art cogeneration facility fueled by natural gas.
The $37-million plant, scheduled to be in operation in 1995, will allow MIT to produce about 75 percent of its energy needs. The plant will generate electricity and steam, providing power, heat and cooling for much of the campus.
The projected annual energy-budget savings is 15 to 20 percent. The new plant will generate 22 MWe (megawatts) of electricity.
In addition, the new facility will:
Improve air quality by reducing pollutant emissions by 45 percent, a level equivalent to reducing daily vehicle commutes to and from Cambridge by 13,000 round trips. That amounts to a 5.3 percent reduction in total daily commutes.
Be 18 percent more efficient because the combustion of a single fuel-natural gas-will cogenerate steam and electricity.
Reduce by 9 million gallons a year the region' s dependence on imported oil by switching to natural gas.
In addition, based on present projections, it is expected that MIT's decision to provide 75 percent of its power needs will lower the need for Cambridge Electric Light Company (CELCO) infrastructure and result in long-term savings to CELCO and its customers.
MIT will continue to be a major customer of CELCO, from which it will purchase about 25 percent of its electricity needs. MIT expects to pay CELCO about $2.5 million annually, and the Institute will continue to be one of the system's larger rate payers.
MIT has commissioned Parsons Main, Inc., of Boston to design the facility. Parsons Main also will provide construction assistance and start-up services.
The work will involve replacing two of the five existing oil-fueled boilers with new cogeneration units and upgrading the others, which will be used as backup units.
Cogeneration is the use of one fuel to generate two forms of energy. In the MIT project, a 19,000 kilowatt (kW) electric generator will be powered by a natural-gas turbine engine producing electricity. The resultant hot exhaust gases will be used to produce steam in a heat-recovery generator. Because one fuel fulfills two purposes, cogeneration is 18 percent more efficient than generating electricity and steam in independent operations.
The new facility will be located on the site of MIT's present central utility plant at 59 Vassar St., not far from Massachusetts Avenue. The rear of the plant site abuts the railroad right of way.
When it goes on line in 1995, the cogeneration facility will provide the bulk of the energy needs of all of the MIT campus except that portion north of the railroad tracks that cross Massachusetts Avenue.
Part of the cogeneration project involves replacing some of the campus electrical distribution system, which contains many components that are approaching their life expectancy. Work on this aspect of the project began in June and required a shutdown of electrical service for varying times in several buildings in June and July and earlier this month.
A version of this article appeared in the August 25, 1993 issue of MIT Tech Talk (Volume 38, Number 3).