MIT to upgrade cogeneration plant with new natural gas turbines by 2020

Enhancements part of Climate Action Plan to reduce campus emissions by 32 percent

The MIT Department of Facilities is upgrading the cogeneration, or “cogen,” plant in the Central Utilities Plant (CUP) at 59 Vassar Street by installing new turbines and upgrading the chilled water plant. The new turbines are projected to start providing energy in 2020.

Cogeneration is a means of generating power in which a turbine (in MIT’s case, a natural gas-powered turbine) generates electricity, and a heat recovery steam generator captures waste heat from the turbine’s exhaust. The plant then uses this captured steam for heating and cooling.

The cogeneration plant, which supplies heated and chilled water and about 50 percent of the main campus’s electricity, is part of a portfolio of projects that make up MIT’s Climate Action Plan, which MIT announced in October 2015. The Climate Action Plan’s mission is to reduce campus emissions by at least 32 percent by 2030. MIT is currently on track to surpass this goal, Director of Utilities Ken Packard told The Tech in an interview Tuesday.

Built in 1995, the CUP initially had one turbine which produced, on average, approximately 20 megawatts (MW) of power and 1,800 pounds of steam. In 1995, MIT’s peak load was 22 MW; it is now 38 MW. This peak load is projected to increase to 42 MW when MIT.nano and the new undergraduate and graduate dorms are completed.

In addition, the current turbine is nearing the end of its projected 20-year lifespan and will need to be replaced with two new turbines, each equipped with a heat recovery steam generator. The new plant will produce 44 MW of power and 3,000 pounds of steam.

However, the CUP will not necessarily require another upgrade 20 years in the future. “I think we’re going to have some optionality on that,” Packard said. “This turbine will have some rigorous service from the manufacturer itself, and I think it will be MIT’s choice in how they reinvest in this turbine setup over the life of the turbines and how they want to extend it.”

MIT initiated permit reviews for CUP upgrades in December 2015. After approvals from the Massachusetts Department of Energy, MIT began construction this July and projects that the upgrade will be complete in 2020.

“Upgrades to the central utility plant will ensure that it operates far more efficiently, fully offsetting the expected 10% increase in energy demand due to campus growth,” Maria Zuber, vice president for research, wrote in an email to The Tech yesterday.

The new plant will use natural gas instead of fuel oil as the current plant does, except in cases of emergency. In addition to having a lower carbon footprint than fuel oil, natural gas is also currently the cheapest fuel.

Two turbines as opposed to one will also increase the CUP’s resiliency, which is important in preparing for emergency conditions and heat needs.

“We’re not going to solve [climate change] with a silver bullet, it’s going to be silver BBs, the project being one of the BBs in that portfolio,” Packard said.

In addition to the cogen plant, the Climate Action Plan also includes projects to reduce buildings’ energy demands, as well as the Summit Farms solar plant in North Carolina, from which MIT currently imports 17 percent of campus electricity. MIT aimed to source 40 percent of its power from the plant when it first opened last year.

MIT is working “to meet carbon neutrality in the context of our own campus [and] what’s feasible in a dense urban environment that requires completely resilient power systems,” Director of Sustainability Julie Newman said in a phone interview with The Tech Tuesday.

The new facility will have windows to allow passerby a view of the energy machinery inside. It will also have a presentation center where MIT can educate the community about how the CUP functions and what MIT is doing to solve the energy crisis. MIT will continue to give tours for students and the public.