CalFinder Q&A: Determining LEED Points for Solar Thermal Systems

From on March 05, 2009 in Green Remodeling

A question from John Hurley: “We are putting together several proposals for a CA state university for solar thermal system for a dormitory. It will only be a pre-heat water system due to constraints on size. We will have either 24 collectors with 500 gallons of storage or 48 collectors with 1K gallons of storage. How can I find out the LEED points this system would contribute to the project? They are hoping the LEED rating will be Gold.” John, leedcertified.jpg While the size of the solar thermal system will certainly affect its impact on the building’s Leadership in Energy and Environmental Design (LEED) rating, points awarded for the system are calculated not by size but by percentages. That is, the percentage of the building’s total energy use produced on-site by the solar system. For existing buildings, LEED’s Energy and Atmosphere Credit offers 1 point for each 3% of the building’s total energy produced by renewable energy. Therefore, calculating your solar thermal system’s contribution will require at least an estimation of the expected performance and resultant energy savings from the solar hot water system. For more specific information, the U.S. Green Building Council (USGBC), which administers LEED ratings, offers free PDF downloads that break down the rating system for each project category (existing buildings, new construction, etc.), or you can purchase a reference guide for step-by-step instructions on obtaining LEED certification. As for which level of certification the dormitory can achieve, that depends on a wide variety of factors. Much more than a solar thermal system will be needed to achieve LEED-Gold certification, although a solar thermal system will be a huge help. Other helpful links: The Harvard University Office for Sustainability summarizes renewable energy and LEED excellently. Wikipedia offers a broader but equally detailed outline of LEED requirements and the point system.