Cogeneration: a sustainable choice

Cogeneration is a clean, efficient, and cost-effective choice for power production. Its benefits are the result of generating two types of energy from one fuel. In MIT’s case, electrical and thermal energy are both generated from a single natural gas turbine. The necessary replacement of the existing cogeneration turbine in the Central Utilities Plant (CUP) presents MIT with a valuable opportunity to renew and strengthen its commitment to energy conservation and effective climate change mitigation.

Pollutant reductions

  • The upgraded CUP will use natural gas for all normal operations, lowering the plant's regulated pollutant emissions more than 25% from 2014 emissions levels.
  • The two new turbines will be cleaner and more efficient. Their state-of-the-art emissions controls include catalysts that will reduce the plant's NOx (nitrogen oxides) emissions by 90%.
  • MIT’s new gas supply agreement with Eversource will enable the plant to run entirely on natural gas by 2020, eliminating the use of fuel oil except for emergencies and testing. This will further reduce emissions. 
  • When upgraded, the plant’s boilers will all be compatible with cleaner #2 fuel, eliminating the use of #6 oil on campus by 2019. On the rare occasions when fuel oil is required for testing or during an emergency, only #2 fuel will be used.
  • MIT's power system also has new cooling towers with high-efficiency drift eliminators that help reduce particulate emissions and conserve water.

Greenhouse gas reductions

  • The upgraded plant supports MIT’s goal of reducing campus greenhouse gas (GHG) emissions at least 32% by 2030. 
  • The upgrades to the plant will reduce MIT's GHG emissions by 10% in 2020, which will offset a projected 10% increase in GHG emissions due to energy demands created by new buildings and program growth. 
  • This reduction is above and beyond the GHG emissions benefits that stem from MIT's original shift to cogeneration in 1995. Since the cogeneration plant first came on line, MIT has achieved annual reductions in GHG emissions of 15%-20% compared to conventional boilers and utility power. 
  • During its first 20 years of cogeneration, the Institute avoided an average of 68,000 metric tons of carbon dioxide emissions each year, according to the EPA. 
  • In 2013 alone, the GHG emissions avoided by MIT were equal to the emissions generated by the electricity use in more than 8,000 single-family homes over a period of one year. 
  • The existing plant received the Energy Star Combined Heat and Power Award  in 2002 for environmental excellence from the U.S. Environmental Protection Agency (EPA) and the Department of Energy. 

In MIT’s cogeneration plant, a natural gas turbine powers a generator to produce electricity for campus buildings. Waste heat from the turbine exhaust is converted into thermal energy by a heat recovery steam generator, and the resulting steam and hot water are used for on-campus heating and cooling. The plant upgrade will increase its power capacity while reducing emissions.