Renewable Energy per LEED

The LEED Rating Systems offer two opportunities to take advantage of renewable energy sources. The most direct opportunity is through Energy and Atmosphere credit 2 (this number is for BD+C- others have a similar credit with a different number), which is for on-site renewable energy. This means producing energy on site from a renewable source like a photovoltaic panel or a wind turbine and using it to directly power your building. The other opportunity is with Energy and Atmosphere credit 6 (BD+C) for “Green Power”. Green Power means purchasing grid-source renewable energy. This is a little bit like buying carbon offsets. You typically have the option of either paying an small increase per kilowatt hour to your local utility company which acts as an incentive for them to invest in renewable strategies like wind farms or solar arrays or buying “Green Tags” or Renewable Energy Certificates (RECs) from an energy provider anywhere in the country. Either way, you will receive the same energy from the utility grid for your project, but the idea is that you will be spurring the development of grid-source renewable energy sources through your financial incentive.

For both the on site renewable energy credit and the Green Power credit, the types of energy sources that count as “renewable” are basically the same (but done on much different scales). The following sources DO count as renewable for the purposes of LEED:

The following systems do NOT count as renewable:

The biggest confusion on the on site renewable energy credit always seems to stem from what is an acceptable “geothermal” system vs. the unacceptable “geo-exchange” system. This comes down to a matter of semantics. Fairly recently, ground source heat pumps have become a very popular mechanical system and are often refered to by manufacturers and system designers as “geothermal” systems. In actuality, these are geo-exchange systems where the ground is used as a heat source and a heat sink in the form of open or closed wells or loops, but the system still relies on electric or gas heating/cooling to supplement the temperate water that is run through the ground. The type of geothermal that is considered renewable by LEED is deep earth water or steam that is directly used to produce power or used directly as heat.

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4 thoughts on “Renewable Energy per LEED

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  2. My company is considering a geothermal system for an industrial facility. The proposed system is a well of approximately 150 meters deep, where water of appr 10 Deg C is pumped up and directly used for cooling of the building in summer time. However the same water will be used during wintertime for heating by using a heatpump.

    This would meet the LEED requirement of “deep” however would the use of a heat pump (vapor-compression system for heat transfer) disqualify this application for the on-site renewable credit?

    The LEED guidance document confused me:

    Geothermal energy systems using deep earth water or steam sources (and not using vapor compression systems for heat transfer) may be eligible for this credit. These systems may either produce electric power or provide thermal energy for primary use at the building.

    Geo-exchange Systems: (a.k.a. geothermal or ground-source heat pumps) Earth-coupled HVAC applications which do not obtain significant quantities of deep-earth heat, and use vapor-compression systems for heat transfer are not eligible as renewable energy systems. These systems are adequately addressed in EA Prerequisite 2, and may be considered under EA Credit 1.

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    1. Jeff- unfortunately what you are talking about for your project is still considered “geo-exchange”, so it wouldn’t be able to be used as “renewable energy” by LEED standards. When they say “deep earth” they are talking about much deeper than 150 meters and the water from these sources is much much hotter than the water you will be getting from your system.

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