CS-2009 EAc4: Enhanced Refrigerant Management 1-2 points

The intent of Energy and Atmosphere Credit 4, Enhanced Refrigerant Management is to Reduce ozone depletion and support early compliance with the Montreal Protocol while minimizing direct contributions to global warming. Our project is a high-rise mixed use (mostly residential, but partly retail and commercial) building being built in a new section of Dubai and will be connected to a new District Cooling Plant using HFC-134a for all of its cooling demand. The project has no small HVAC or Refrigerant systems and plans to use in-ceiling sprinklers for fire suppression in corridors and occupied spaces in the building. Local code requires that the electronic building management equipment room (an area comprising less than 1% of GFA) for the building employ a different system for fire suppression utilizing the compound FM200. This is a chemical suppression system made by Dupont Chemical company. Upon our initial research, FM200 appeared to be noncompliant with Montreal Protocol Phase out efforts because a key ingredient in production of FM200 is HCFC-22. However, according to the manufacturer, the HCFC-22 is used and entirely consumed (except for trace quantities) in the production of FM200. In other words, the HCFC-22 is used in the chemical reaction required to create the fire suppression chemical, the reaction causes the HCFC to be changed to an HFC (HFC-227ea as listed on the manufacturer\'s MSDS at http://msds.dupont.com/msds/pdfs/EN/PEN_09004a358037d86b.pdf). As a result, by the time the product arrives packaged at our project site it is no longer an HCFC. In the event of release through leakage or a fire, this chemical will not contribute to ozone depletion. We believe that this product should not negate our capacity to achieve EA Credit 4 as the final use product is, in fact, an HFC. Please confirm that our approach to this credit is correct and will meet the intent and requirements of the credit.

EA Credit 4 has been restructured between LEED-NC 2.1 & 2.2 to take into account the global warming impacts of HVAC equipment. The premise is that HFC refrigerants, preferred for their low ozone depletion potential, are less efficient than their CFC and HCFC counterparts, and thus cause more emissions from electricity generation. The formula developed guides applicants to utilize systems and refrigerants that optimize global warming and ozone depletion reductions, and uses the ratio of refrigerant to cooling capacity as a measure. We believe that refrigerant charge is a good indicator of Ozone Depletion Potential, but not of Global Warming Potential. Our experience with numerous projects, including supermarket and school projects, all of which use packaged rooftop units and ductless split systems, has created confusion and conflicting rewards in the goal of using less refrigerant. Case in point, the Trane 5-ton standard efficiency packaged rooftop unit has a refrigerant charge of 1.88 lbs/ton (meets the criteria of the credit as written) and uses 1.05 kW/ton, while the Trane 5-ton High Efficiency has a refrigerant charge of 2.5 lbs/ton (does NOT meet the criteria of the credit) and uses 0.95 kW/ton. The high-efficiency unit uses 10% less electricity, but still does not meet the credit despite a reduction in emissions due to less electricity used. This example is typical of major HVAC manufacturers of packaged rooftop units, and not simply an anomaly. Furthermore, supermarkets are heavy users of refrigeration equipment, and almost always utilize remote condensers and heat rejecters to prevent excess heat loads within the sales area. The refrigerated cases and freezers are connected to the condensers through refrigerant lines, typically using the HFC refrigerant R404a. The constraints of the building type and the distance between the heat rejection equipment and the cases necessitates using large amounts of refrigerant, sometimes up to 6 lbs/ton, and cannot possibly meet the criteria of the credit. The mere existence of this equipment precludes supermarket buildings from receiving this credit, despite the use of environmentally friendly refrigerants and waste heat recovery technology to assist in dehumidification and hot water heating. Similarly, the credit does not directly address the use of ductless split systems. This type of unit is most effective for conditioning spaces that are difficult to reach with traditional ductwork, and by nature must use refrigerant to connect the condensing unit to the fan coil unit. The quantity of refrigerant is indicative of the distance between the two and not necessarily of the efficiency of the unit. In the context of the supermarket building type: 1) Should we specify less efficient HVAC equipment that meets the credit instead of pursuing increased energy efficiency? Does that meet the intent of the credit? 2) Can we exclude the refrigeration equipment from this calculation? If not, what is the best practice recommended to achieve this credit, as the current criteria are unreachable? 3) Can the limit for ductless split systems be raised, or does achievement of this credit create a de facto requirement to eliminate use of these types of systems? Please contact Andrew Ellsworth at andrew@evolveea.com or 412.362.2100 to obtain supporting documentation for this CIR in the form of charts, graphs and cut sheets. This information is critical to understanding the issue being raised.