of ducted central air conditioning systems—see Section A.2. Heating Fuel Interactive Effects The heating fuel IE factor is a ratio of the whole-building heating fuel increase to the electric energy savings resulting from a lighting retrofit. It is calculated in the following manner: Table 7 expresses the heating fuel IE factor in BTU/kWh—the annual increase in heating fuel use in BTU per annual kWh of lighting savings. This factor accounts for interactive effects on heating requirements only for homes that are not heated with electricity; the electric IE factors in Sections 3.1 and 3.2 account for heating interactive effects in electric-heated homes. Replacing incandescent bulbs with more efficient bulbs results in 1,902 BTU in increased heating consumption on average per kWh of electricity saved at the lighting end use. The heating IE factor for gas-heated homes is larger because these homes tend to be less efficient—based on Home Energy Rating System (HERS) scores—than other homes. Table 7: Heating Fuel IE Factors BTU/kWh – Heating IE Factor in Heating fuel Number of Homes BTU/kWha Oil, LP, or biomass 1,887 118 Natural gas 1,941 48 Overall 166 1,902 a Weighted with heating fuel proportional weight—see Section A.2. Table 8 presents the same information as Table 7, converted from BTU to units of heating fuel. On average, homes heated with fossil fuels will use an extra 0.01 to 0.02 units of fuel per kWh of lighting savings. Table 8: Heating Fuel IE Factors Units of Fuel/kWha – Heating IE Factor in Number of Heating fuel Fuel Units/kWh Homes Oil (gallons) 0.014 112 Natural gas (ccf) 0.019 46 LP (gallons) 0.019 3 Biomass (MMBtu) 0.002 3 Overall (MMBtu) 166 0.002 a Weighted with heating fuel proportional weight—see Section A.2.
of ducted central air conditioning systems—see Section A.2. Heating Fuel Interactive Effects The heating fuel IE factor is a ratio of the whole-building heating fuel increase to the electric energy savings resulting from a lighting retrofit. It is calculated in the following manner: Table 7 expresses the heating fuel IE factor in BTU/kWh—the annual increase in heating fuel use in BTU per annual kWh of lighting savings. This factor accounts for interactive effects on heating requirements only for homes that are not heated with electricity; the electric IE factors in Sections 3.1 and 3.2 account for heating interactive effects in electric-heated homes. Replacing incandescent bulbs with more efficient bulbs results in 1,902 BTU in increased heating consumption on average per kWh of electricity saved at the lighting end use. The heating IE factor for gas-heated homes is larger because these homes tend to be less efficient—based on Home Energy Rating System (HERS) scores—than other homes. Table 7: Heating Fuel IE Factors – BTU/kWh Heating fuel Number of Homes Heating IE Factor in BTU/kWha Oil, LP, or biomass 118 1,887 Natural gas 48 1,941 Overall 166 1,902 a Weighted with heating fuel proportional weight—see Section A.2. Table 8 presents the same information as Table 7, converted from BTU to units of heating fuel. On average, homes heated with fossil fuels will use an extra 0.01 to 0.02 units of fuel per kWh of lighting savings. Table 8: Heating Fuel IE Factors – Units of Fuel/kWha Heating fuel Number of Homes Heating IE Factor in Fuel Units/kWh Oil (gallons) 112 0.014 Natural gas (ccf) 46 0.019 LP (gallons) 3 0.019 Biomass (MMBtu) 3 0.002 Overall (MMBtu) 166 0.002 a Weighted with heating fuel proportional weight—see Section A.2.
R67-Residential%20Lighting%20Interactive%20Effects%2C%20Review%20Draft%209-17-14.docx