There is significant confusion around the requirements for calculating and documenting refrigerant leakage rates for existing equipment. The EPA has published three different formulas, two of which are contained in the reporting rules and one which is in a guidance document about the reporting rules for industrial refrigeration systems. Additionally, the Rating System refers to the “EPA Clean Air Act, Title VI, Rule 608 procedures governing refrigerant management and reporting” but those procedures are actually contained in 40 CFR Part 82, Subpart F. These rules provide triggers and requirements when annual refrigerant leakage rates exceed a threshold, with the required corrective actions including repair, decommissioning, and retrofit/replacement. Some project teams report that refrigerant pressures are checked on regular intervals but that refrigerant is only added when the loss is significant. Please clarify what methods may be used to calculate refrigerant leakage rates, whether the rates should be calculated for the performance period only or the rate calculated for the most recent refrigerant addition should be used, and what project teams are required to do if the 5% annual and 30% lifetime leakage rates are exceeded.
Leakage Rate Calculation:
The annual refrigerant leakage rate (Lr) must be calculated using a method recognized by the U.S. EPA pursuant to the EPA Clean Air Act Title VI, Rule 608, and must be based on the most recent amount of refrigerant added. The time elapsed is the number of days in between the two most recent refrigerant charges, regardless of the performance period start date and regardless of whether refrigerant is checked on a regular basis (e.g., annually). This applies to both EAc5 and EAp3 for projects with CFC-based refrigerant demonstrating compliance with the maximum annual refrigerant leakage rate (5%).
Refrigerant Impact per Ton:
For recertification projects, the refrigerant impact per ton is based on the most recent refrigerant addition according to Table 1. Credit Compliance Guidance from the Recertification Guidance, April 2013. This means that if the recertification performance period is five years long and refrigerant was added during the first, third and fourth year, the refrigerant leakage rate is based on the refrigerant added during the fourth year and the number of days between the third and fourth year refrigerant additions. The project is required to track refrigerant leakage throughout the entire recertification performance period, but only the most recent refrigerant addition is used in the calculation of refrigerant leakage rate, regardless of whether it is more or less than previous additions.
CFC-based Refrigerant:
For recertification projects with CFC-based refrigerant, the refrigerant leakage rate must be calculated for each refrigerant addition during the performance period to demonstrate whether the maximum annual refrigerant leakage rate (5%) has been continuously met throughout the entire recertification performance period. For both initial certification and recertification projects, if the 5% annual refrigerant leakage rate is exceeded (including catastrophic equipment failure resulting in significant refrigerant leakage) , the project is still eligible for EAp3 as long as the EPA Clean Air Act Title VI, Section 608 guidelines (http://www.epa.gov/ozone/title6/608/608fact.html), as stated below are followed:
1. Owners or operators of refrigeration and air-conditioning equipment with refrigerant charges greater than 50 pounds are required to repair leaks within 30 days when those leaks result in the loss of more than a certain percentage of the equipment's refrigerant charge over a year. For the commercial (e.g. grocery stores and warehouses) and industrial process refrigeration sectors, leaks must be repaired within 30 days when the equipment leaks at a rate that would release 35 percent or more of the charge over a year. For all other sectors, including comfort cooling (such as building chillers), leaks must be repaired when the appliance leaks at a rate that would release 15 percent or more of the charge over a year.
2. For LEED purposes, leaks must be repaired within 30 days when the appliance leaks at a rate that would release 5 percent or more of the charge over a year. The equipment is not required to be decommissioned or replaced at this time.
3.The EPA Clean Air Act Title VI, Section 608 guidelines also state that, “This requirement is waived if, within 30 days of discovery, owners develop a one-year retrofit or retirement plan for the leaking equipment. Owners of industrial process refrigeration equipment may qualify for additional time under certain circumstances”.
End of Life Refrigerant Leakage Calculation for Equipment with CFC-based Refrigerant:
The maximum 30% end of life leakage rate shall be calculated based on the total amount of refrigerant lost over the life of the equipment through the end of the performance period. If a project has experienced a catastrophic equipment failure resulting in a refrigerant leakage rate exceeding 30% during the performance period, the project is not eligible for certification unless the project commits to decommissioning or replacing the equipment within one-year from the end of the performance period. This applies to both initial certification and recertification.
International Applicability:
The Montreal Protocol has achieved universal ratification and most project locations should have local requirements with procedures for limiting the atmospheric discharge of refrigerants. Project teams wishing to use local requirements should contact USGBC early in the project to ensure that the alternative standard is acceptable.