Add rim joist insulation 61% 109 Add solar hot water system 61% 109 Add photovoltaic 60% 108 Add foundation wall insulation 51% 91 Increase oil boiler AFUE 46% 83 Add vaulted ceiling insulation 43% 78 Add duct insulation 43% 78 Reduce duct leakage 41% 74 *Note that central heating systems were upgraded for a portion of the sample. While ductless mini-splits were included in every model they were sized to meet the cooling load of each home, not the heating load. As a result, the existing heating equipment was modeled to fulfill the remainder of the heating load and was upgraded where applicable. Table : Measures Included in Comprehensive Technical Potential Model Run—Less Common* Sample Measure % of Sites Size Upgrade freezer 33% 60 Install ECM fan motor 29% 53 Upgrade dehumidifier 27% 49 Replace gas storage water heater with instantaneous 24% 43 Replace tankless coil with indirect water heater 24% 43 Replace electric DHW with heat pump DHW 23% 42 Add DHW pipe insulation 22% 39 Increase oil furnace AFUE 16% 29 Increase gas furnace AFUE 14% 26 Increase gas boiler AFUE 13% 24 Replace oil storage DHW with more efficient oil storage 5% 9 Replace LP storage water heater with instantaneous 3% 6 Install air source heat pump 2% 4 Increase propane furnace AFUE 1% 2 Increase propane boiler AFUE 1% 2 Replace gas storage DHW with more efficient gas storage 0% 0 Replace gas storage DHW with gas condensing 0% 0 Replace LP storage DHW with more efficient LP storage 0% 0 Replace LP storage water heater with LP condensing 0% 0 Upgrade central air conditioner 0% 0 Upgrade room air conditioners 0% 0 Install ground source heat pump 0% 0 *Note that central heating systems were upgraded for a portion of the sample. While ductless mini-splits were included in every model they were sized to meet the cooling load of each home, not the heating load. As a result, the existing
Add rim joist insulation 109 61% Add solar hot water system 109 61% Add photovoltaic 108 60% Add foundation wall insulation 91 51% Increase oil boiler AFUE 83 46% Add vaulted ceiling insulation 78 43% Add duct insulation 78 43% Reduce duct leakage 74 41% *Note that central heating systems were upgraded for a portion of the sample. While ductless mini-splits were included in every model they were sized to meet the cooling load of each home, not the heating load. As a result, the existing heating equipment was modeled to fulfill the remainder of the heating load and was upgraded where applicable. Table : Measures Included in Comprehensive Technical Potential Model Run—Less Common* Measure Sample Size % of Sites Upgrade freezer 60 33% Install ECM fan motor 53 29% Upgrade dehumidifier 49 27% Replace gas storage water heater with instantaneous 43 24% Replace tankless coil with indirect water heater 43 24% Replace electric DHW with heat pump DHW 42 23% Add DHW pipe insulation 39 22% Increase oil furnace AFUE 29 16% Increase gas furnace AFUE 26 14% Increase gas boiler AFUE 24 13% Replace oil storage DHW with more efficient oil storage 9 5% Replace LP storage water heater with instantaneous 6 3% Install air source heat pump 4 2% Increase propane furnace AFUE 2 1% Increase propane boiler AFUE 2 1% Replace gas storage DHW with more efficient gas storage 0 0% Replace gas storage DHW with gas condensing 0 0% Replace LP storage DHW with more efficient LP storage 0 0% Replace LP storage water heater with LP condensing 0 0% Upgrade central air conditioner 0 0% Upgrade room air conditioners 0 0% Install ground source heat pump 0 0% *Note that central heating systems were upgraded for a portion of the sample. While ductless mini-splits were included in every model they were sized to meet the cooling load of each home, not the heating load. As a result, the existing
R15_Single-Family%20Potential%20Study_Review%20Draft_9-05-14.docx