The Power Plant Expansion project is an expansion and addition to the existing boiler, chiller and power plant building at a Medical School campus. The project is seeking certification under LEED for New Construction v2.2. The main purpose of the addition and expansion will be to house new high pressure steam equipment, a water chiller, and an electric generator. This new equipment will be sized primarily for the new 300,000 SF R&D/lab/office building being designed for the campus, and there will also be some redundancy/back-up capacity for the existing plant equipment. There will be some accessory control spaces and workshop spaces to service the new plant equipment. There will also be a small (5,000 SF +/-) addition to the opposite side of the building for office space. Please confirm that the following project approach will be acceptable to USGBC for LEED EAC1 compliance and certification: We propose to include only the energy used to heat, cool, ventilate, and light the LEED project areas in the EAc1 energy model, in accordance with ASHRAE 90.1-2004, Appendix G. We will also include domestic hot water generation as normally calculated in LEED models. We propose that the energy input into the steam boiler, chiller and generator, and the energy output from the building (in the form of steam, chilled water, and electricity feeding the campus) be considered process energy, because the purpose of the new equipment and the new space is to create steam, chilled water and electricity for the other buildings on campus. We will need to include the impact of the net process energy on the systems within the project area (for example, the heat output from the boiler will need to be ventilated out of the boiler room, and it may be an opportunity for heat recovery). If we cannot use this approach, the large quantity of energy used in the boiler plant space to make the steam, chilled water, and electricity for the campus will dwarf the small amount of energy needed to maintain HVAC, lighting and domestic hot water in the project area. It will be extremely difficult for the energy model to show the required energy savings for LEED certification.
The applicant is requesting clarification that the energy generated (steam, chilled water & electricity) from a campus plant be considered process energy. Power generated within the plant building and distributed to other campus buildings may be considered process energy while applying the benefit to any uses within the plant building. However, resultant heat generated that is used for the energy systems of the plant building will not be termed process energy, and will have to be considered in the energy model in accordance with the CHP document. As such the plant building should only account for energy consumption of district thermal energy and district power generated that will be used within the building. Refer documents on District Energy Systems and Combined Heat & Power Systems to apply the guidelines. The documents can be found on the USGBC web-site at the following URL: http://www.usgbc.org/ShowFile.aspx?DocumentID=4176 and http://www.usgbc.org/ShowFile.aspx?DocumentID=1354 Applicable Internationally.