This credit rewards projects that select mechanical equipment and refrigerants with lower ozone depletion and global warming impacts. The credit calculation takes several other variables into account—including equipment life, refrigerant leakage rateThe speed at which an appliance loses refrigerant, measured between refrigerant charges or over 12 months, whichever is shorter. The leakage rate is expressed in terms of the percentage of the appliance's full charge that would be lost over a 12-month period if the rate stabilized. (EPA Clean Air Act, Title VI, Rule 608)., and the ratio of coolant charge to cooling capacity—in order to determine compliance.
All permanently installed HVAC&R equipment with more than 0.5 lbs of refrigerant—including chillers; unitary HVAC equipment (split and packaged); room and window air-conditioners; computer, data center, and telecom room cooling units; and commercial refrigeration equipment—is addressed by this credit.
This is a relatively easy credit to achieve if your project has a centralized cooling plant, with a favorable “coolant charge to cooling capacity” ratio. But even for projects with smaller, more dispersed units, this credit should be achievable if you consider the credit requirements early. The best way to confirm compliance is to run the calculations as soon as an HVAC system is proposed.
If your project already has designed an HVAC system and now wants to change the refrigerant to meet the credit, you will find that it may not be as simple as swapping out the coolant or the compressor unit for a more environmentally benign choice. Rather, your entire HVAC system may have to be resized to accommodate the different capacities and efficiencies of the newer units.
Only the default leakage rate of 2% is accepted in the credit calculations.
All HVAC&R equipment that will serve the project building should be included in the calculations.
Any permanently installed piece of equipment containing greater than 0.5 lbs. of refrigerant and included in the project scope should be included in calculations.
While a phase-out is allowed in the prerequisite, this credit is like other credits in that it must be achieved as part of the LEED scope of work. The work should be completed during construction.
To reduce ozone depletion and support early compliance with the Montreal Protocol while minimizing direct contributions to climate change1. Climate change refers to any significant change in measures of climate (such as temperature, precipitation, or wind) lasting for an extended period (decades or longer). (U.S. Environmental Protection Agency, 2008)
2.The increase in global average temperatures being caused by a buildup of CO2 and other greenhouse gases in the atmosphere. This temperature change is leading to changes in circulation patterns in the air and in the oceans, which are affecting climates differently in different places. Among the predicted effects are a significant cooling in Western Europe due to changes in the jet stream, and rising sea levels due to the melting of polar ice and glaciers..
Do not use refrigerants, or use only refrigerants (naturally occurring or synthetic) that have an ozone depletion potential (ODPOzone Depletion Potential (ODP) is a measure of ozone impact a chemical has relative to CFC-11 (trichlorofluoromethane), which has a ODP of 1. ) of zero and a global warming potential (GWPGlobal Warming Potential (GWP) is a measure of substances’ ability to absorb heat and warm the atmosphere relative to carbon dioxide, which has a GWP of 1, over a given time period. ) of less than 50.
Select refrigerants that are used in heating, ventilating, air-conditioning, and refrigeration (HVAC&R) equipment to minimize or eliminate the emission of compounds that contribute to ozone depletion and climate change1. Climate change refers to any significant change in measures of climate (such as temperature, precipitation, or wind) lasting for an extended period (decades or longer). (U.S. Environmental Protection Agency, 2008)
2.The increase in global average temperatures being caused by a buildup of CO2 and other greenhouse gases in the atmosphere. This temperature change is leading to changes in circulation patterns in the air and in the oceans, which are affecting climates differently in different places. Among the predicted effects are a significant cooling in Western Europe due to changes in the jet stream, and rising sea levels due to the melting of polar ice and glaciers.. The combination of all new and existing base buildingThe base building includes elements such as the structure, envelope, and building-level mechanical systems, such as central HVAC, and materials and products installed in the project (e.g., flooring, casework, wall coverings). and tenant HVAC&R equipment that serve the project must comply with the following formula:
For multiple types of equipment, calculate a weighted average of all base building HVAC&R equipment, using the following formula:
We are using a heat pumpA type of heating and/or cooling equipment that draws heat into a building from outside and, during the cooling season, ejects heat from the building to the outside. Heat pumps are vapor-compression refrigeration systems whose indoor/outdoor coils are used reversibly as condensers or evaporators, depending on the need for heating or cooling. In the 2003 CBECS, specific information was collected on whether the heat pump system was a packaged unit, residential-type split system, or individual room heat pump, and whether the heat pump was air source, ground source, or water source. type water heater. The refrigerant capacity for the unit is over the 0.5 lb threshold. Does anyone have any advice as to determine the nominal capacity of the heat pump portion of the water heater since that is what needs to be compared to the refrigerant charge?
Also I was planning on listing the equipment as a packaged heat pump. Does that seem appropriate?
I've not had experience including heating-only equipment in this credit and it'd be great to hear from anyone that has, since this has actually been puzzling me for a while! The credit language is written as if it applies to heating, cooling, ventilation, and refrigeration, but only cooling and refrigeration is ever addressed.
My thought is that the best approach, from the standpoint of the credit intent and the calculations, would be to use the nominal heating capacity of the equipment (found on the cutsheet or submittal), convert it to tons to keep the units correct in the calculation, and then include it in the table.
If it's serving water heating and not space heating, it may be better to list it as an "other" type of equipment with a ten-year lifespan. You can use a longer value for the lifespan if the manufacturer is able to provide backup documentation, such as a warranty period.
I am working on a CS project and the drawings do not have any planned ref equipment since this will be at the tenants discretion to decide at a later date.
If our plans do not include ref equipment, are we still able to receive points for this credit? What is required to submit for certification if we do not have this equipment included in the drawings?
Alanna, this is covered on page 15 of the LEED Reference Guide. Basically you can only count what's in your CS scope to earn the credit, unless you use a tenant lease agreement.
LEEDuser is produced by BuildingGreen, Inc., with YR&G authoring most of the original content. LEEDuser enjoys ongoing collaboration with USGBC. Read more about our team
Copyright 2017 – BuildingGreen, Inc.