SINGLE-FAMILY HOME OPERATING COSTS: NATURAL GAS VS. RESIDENTIAL HEATING OIL, PROPANE AND ELECTRIC Average costs for a three person, 2300 square foot single-family home in the DC metropolitan region utilizing space heating, water heating, cooking and drying.

Estimated Annual Savings if Converted Equipment Description Operating Costs 1,2,3,4 to Natural Gas Operating Life-Cycle Cost 9 DC MD VA DC MD VA DC MD VA

Space Heating 5,6,7 Natural Gas - Average Furnace, 80% AFUE $500 $514 $504 - - - $7,500 $7,707 $7,561 Residential Heating Oil (#2) - Average Furnace, 80% AFUE 5 $1,238 $1,238 $1,238 $738 $725 $734 $18,576 $18,576 $18,576 Propane - Average Furnace, 80% AFUE $1,912 $1,912 $1,912 $1,412 $1,398 $1,408 $28,674 $28,674 $28,674 All Electric Furnace/Resistance Heat 12 $2,014 $2,179 $1,703 $1,514 $1,665 $1,199 $30,213 $32,683 $25,551 Electric - Standard Efficiency Heat Pump, 8.7 HSPF7,15 $858 $929 $726 $359 $415 $222 $12,877 $13,930 $10,890

Natural Gas - High Efficiency Furnace, 92% AFUE $435 $447 $438 - - - $6,521 $6,702 $6,575 Residential Heating Oil (#2) - High Efficiency Furnace, 92% AFUE $1,077 $1,077 $1,077 $642 $630 $639 $16,153 $16,153 $16,153 Propane - High Efficiency Furnace, 92% AFUE6 $1,662 $1,662 $1,662 $1,228 $1,215 $1,224 $24,934 $24,934 $24,934 Electric - High Efficiency Heat Pump, 9.5 HSPF7,13 $806 $872 $682 $371 $425 $243 $12,091 $13,079 $10,225

Water Heating 5,8 Natural Gas - Standard Water Heater, 0.59 EF $143 $147 $144 - - - $1,855 $1,906 $1,870 Residential Heating Oil (#2) - Standard Water Heater, 0.59 EF $353 $353 $353 $211 $207 $210 $4,594 $4,594 $4,594 Propane - Standard Water Heater, 0.59 EF $546 $546 $546 $403 $399 $402 $7,092 $7,092 $7,092 Electric - Standard Water Heater, 0.9 EF $447 $484 $378 $305 $337 $235 $5,817 $6,292 $4,919

Natural Gas - Condensing Tankless Water Heater, 0.95 EF $89 $91 $89 - - - $1,152 $1,184 $1,161 Residential Heating Oil (#2) - Condensing Tankless Water Heater, 0.93 EF 5 $224 $224 $224 $211 $207 $210 $2,914 $2,914 $2,914 Propane - Condensing Tankless Water Heater, 0.93 EF $346 $346 $346 $403 $399 $402 $4,499 $4,499 $4,499 Electric - High-Performing Water Heater, 0.95 EF $424 $459 $358 $305 $337 $235 $5,511 $5,961 $4,660

Cooking 10 Natural Gas - Standard Cooktop, 40% Efficient $40 $41 $40 - - - $401 $412 $404 Electric - Standard Cooktop, 74% Efficient $104 $112 $88 $64 $71 $47 $1,037 $1,112 $877

Clothes Drying 11 Natural Gas - Standard Dryer, 2.67 EF $30 $31 $30 - - - $298 $307 $301 Electric - Standard Dryer, 3.01 EF $127 $137 $107 $97 $106 $77 $1,266 $1,370 $1,071 Notes:

1 Average gas rate / net therm based on published Washington Gas tariff rate schedules (Residential Heating) and actual net purchased gas charges for the 12 months ending July 2016. Taxes not included.

2 Electric cost / kWh based DOE-published “Average Retail Price of Electricity to Ultimate Customers by End-Use Sector, by State,” April 2016 (Table 5.6.B). Taxes not included. Source: https://www.eia.gov/electricity/monthly/epm_table_grapher.cfm?t=epmt_5_06_b

3 Residential fuel oil rate / gallon based on most recent average 12 months of DOE’s “Central Atlantic (PADD 1B) No. 2 Heating Oil Residential Price (Dollars per Gallon)” from October 2014 through March 2016. Source: http://www.eia.gov/dnav/pet/hist/LeafHandler.ashx?n=PET&s=M_EPD2F_PRS_R1Y_DPG&f=M

4 Propane rate / Gallon based on most recent 12 months of DOE’s “Central Atlantic (PADD 1B) Propane Residential Price (Dollars per Gallon)” from October 2014 - March 2016 Source: http://www.eia.gov/dnav/pet/hist/LeafHandler.ashx?n=PET&s=M_EPLLPA_PRS_R1Y_DPG&f=M

5 Conversion factors: 1 MMBtu = 7.2 gallons #2 heating oil; 10.9 gallons liquid propane; 293 kWh electricity; 10 therms natural gas.

6 Heating load required based on square footage of home with average insulation and standard ceiling height.

7 Heat pump efficiency (HSPF) adjusted for DC region.

8 Daily water heating equipment efficiencies (EF) and analysis based on DOE usage per person in household and regional water temperature.

9 Operating life-cycle cost equal projected annual operating costs X appliance lifespan. (Maintenance is not included.) Furnace life estimated at 15 years per DOE Home Heating Guide. Source: http://www.energy.gov/sites/prod/files/2014/01/f6/homeHeating.pdf). Water heater life estimated at 13 years based on ACEEE Life-Cycle Cost analysis. Source: http://www.aceee.org/node/3068#lcc. All other appliance estimated to have 10-year useful life.

10 Cooking equipment efficiencies (% efficient) and energy consumption based on 2 MMBTU / Yr (20 Therms / Year) usage provided by ESC Carbon Footprint Spreadsheet.

11 Drying equipment efficiencies (EF) and energy consumption based on DOE National Single Family Average of 8 Drying Loads / Week and 7 Lbs / Load provided by ESC Carbon Footprint Spreadsheet.

12 Electric resistance heat (e.g., electric baseboard) is heat generated by converting electricity to heat. 3,412 Btu = 1 kWh (COP = 1).

13 The coefficient of performance or COP of a heat pump is a ratio of heating or cooling provided to work required and is calculated: (Heat Energy Transported)/(Energy Input). COP decreases at colder outdoor temperatures. Where natural gas block rates in place (MD, VA), average net cost/therm estimated by applying block rates to evenly distributed annual total gas use of 900 therms.

AFUE = Annual Fuel Utilization Efficiency http://energy.gov/energysaver/furnaces-and-boilers