The Medical Area Total Energy Plant (MATEP), completed in 1980, is centrally located in the 200 acre Longwood Medical Area (LMA), of Boston. MATEP serves steam, chilled water, and electricity to over 9 million square feet of space in facilities throughout the LMA. This busy neighborhood is home to five major hospitals which have approximately 2,000 beds and serve 103,000 inpatients and 2.4 million outpatients per year. Numerous medical research centers and teaching institutions also are located in the Longwood Medical Area. MATEP's origins date back to 1906 when Harvard University built a powerhouse only yards from where MATEP stands to provide steam and electricity for the Harvard Medical School. When economical electricity became available commercially from the local electric utility, the powerhouse was converted into a steam and chilled water facility. For many years, the converted powerhouse provided low cost heating and cooling service to its customers, most of whom remain customers to this day.
Toward the end of the 1960's, it became apparent that the original powerhouse was becoming obsolete. Studies indicated it could not be relied upon to meet the needs of the growing hospital complex beyond 1980. Planners from Harvard University and area hospitals reviewed alternative methods of meeting the future utility needs of the institutions. These alternatives included having each institution produce its own steam and chilled water, building a central steam and chilled water plant to service all institutions, or constructing a total energy plant. Because the local utility, Boston Edison, did not operate a steam facility in or near the LMA, and chilled water was not available independently, the choices were limited. After a review of the available alternatives, the total energy plant concept was recommended as the most cost effective and fuel efficient way to ensure the availability of utility services on a long-term basis. Based on the analysis and assurances from technical and medical experts that the plant would be environmentally safe, the decision was made to build MATEP. From 1978 to 1998, MATEP remained under the ownership of Harvard University, operated by the Cogeneration Management Corporation.
On June 1, 1998, Advanced Energy Systems (AES) acquired MATEP from Harvard University. After the acquisition of AES by NSTAR, a major electrical, steam and chilled water expansion was undertaken at MATEP to meet the growing needs of the connected facilities and improve the operating efficiency and reliability of the aging plant.
On June 1, 2010 MATEP was acquired by a joint venture between Morgan Stanley Infrastructure Partners and Veolia Energy North America. The joint venture has an O&M contract with Veolia Energy North America as the operator of the plant.