Rating System

LEED BD+C: New Construction, LEED BD+C: Schools, LEED BD+C: Retail, LEED BD+C: Healthcare, LEED BD+C: Data Centers, LEED BD+C: Hospitality, LEED BD+C: Warehouses and Distribution Centers

Rating System Version

v4 - LEED v4, v3 - LEED 2009

Inquiry

Our project is connected to a district energy system which provides both heating and cooling for the building; no additional building-level cooling systems are installed. The district system draws heavily on deep lake cooling with a complement of refrigerant-based cooling. We also have walk-in refrigerators on the premises. We are not permitted to count the deep lake cooling with a refrigerant factor of zero, so because the walk-in refrigerators use refrigerants with a high impact (according to the LEED calculation), we exceed the impact limit of 100 for the credit even though the project?s cooling capacity is largely provided by refrigerant-free sources.\n We propose a calculation methodology that demonstrates a design case reduction of the total refrigerant impact as compared to the baseline case:\n • The baseline case is calculated by factoring the total cooling capacity of the building?s baseline case and a refrigerant impact of 100 per ton. The demand (during the simulated year) is 1496 kW for the baseline case and 1704 (483,9 tons) installed capacity, as per the EAp2 form and the EA Section 1.4 Tables respectively.\n o total design case cooling capacity = 483.9 tons\n o total refrigerant impact = 483.9 x 100 = 48390 \n • The design case factors the labeled capacity on the district energy system?s heat exchanger (district cooling exchanger) and the walk-in refrigerator equipment, and their respective refrigerants. \n o total design case cooling capacity = 393.7 tons\n o total refrigerant impact = 393.7 x 86 = 33798 \n • Total reduction in cooling demand = 393.7 / 483.9 = 81.36 (18.64% reduction)\n • Total reduction in refrigerant impact = 33798 / 48390 = 69.85 (30.15% reduction)\n The calculation confirms that the refrigerant impact reduction is in excess of that associated with the reduced cooling capacity. We would like this to be an ACP.