Approximately what percentage of chillers in existing buildings use CFC-11 as a refrigerant?

The usage of CFC-11 as a refrigerant in existing buildings is a significant consideration in the context of environmental impact and regulatory compliance. CFC-11, or trichlorofluoromethane, is a chlorofluorocarbon that has been largely phased out due to its harmful effects on the ozone layer. However, in older systems, particularly those installed before widespread awareness and regulation, a substantial number of chillers still utilized CFC-11.

Research and industry reports indicate that a considerable portion of existing chillers, particularly those manufactured in the 1970s and 1980s, employed CFC-11 as a refrigerant, and estimates suggest this number hovers around the 30% mark. This level of usage reflects the historical prevalence of CFC-11 in earlier refrigeration technologies. While the phase-out efforts have succeeded in reducing the overall percentage of chillers using this refrigerant, approximately 50% is representative of a realistic estimate within the scope of existing older systems, accounting for those that still have not yet transitioned to more environmentally friendly alternatives.

The higher figures typically ascribed to percentages over 75% are not supported by current assessments, as regulations and industry practices have pushed for the replacement of