CFL Savings Calculator Enter inputs in black. Outputs/results are in blue. Enter Assumptions: Average Daily Use, hours 3 Energy Star Assumption Compact Fluorescent Bulb life, hours 10,000 Most currently available CFLs are rated for 8,000 to 12,000 hours (depending on bulb) North Carolina Average Residential Electricity Rate (cents/kWh) 9.12 Energy Star data Pounds of Coal required to produce 1 kWh electricity: 0.963 0.963 derived from Energy Star assumptions for Coal emissions factor & carbon content Coal CO2 emissions factor (Pounds CO2/kWh coal generation): 2.06 2.06 from Energy Star assumptions NC-specific energy mix emissions factor (Pounds CO2 from overall fuel mix): See NC Electr. Sources & CO 2 tab 1.29 Annual Savings Annual kWh Energy saved per Cost year savings 49.28 $4.49 84.32 $7.69 Coal Savings, pounds per year if 100% coal generation 47.45 81.20 Coal Savings, pounds per year assuming NC fuel mix 28.71 49.12 CO2 savings, pounds per year if 100% coal generation 101.51 173.69 CO2 savings, pounds per year assuming NC fuel mix 63.56 108.77
Replaced Bulb New Bulb Wattage wattage Wattage savings 60 15 45 100 23 77 Bulb Lifetime Savings
Replaced Bulb New Bulb Wattage wattage Wattage savings 60 15 45 100 23 77 Years operation
kWh saved bulb lifetime 450 770
Lifetime Energy Cost Savings $41.04 $70.22
Coal Savings, pounds over CFL life if 100% coal generation 433.35 741.51
Coal Savings, pounds over CFL life assuming NC fuel mix 262.18 448.61
CO2 savings, pounds over CFL life if 100% coal generation 927.00 1586.20
CO2 savings, pounds over CFL life assuming NC fuel mix 580.50 993.30
Costs in $, Coal and CO2 Lifetime Pounds Coal Lifetime Energy used, if 100% Cost coal generation $13.68 144.45 $54.72 577.80 $20.98 221.49 $91.20 963.00 Lifetime Pounds Coal used, assuming NC fuel mix 87.39 349.57 134.00 582.62 Lifetime Pounds CO2 generated, if 100% coal generation 309.00 1236.00 473.80 2060.00 Lifetime Pounds CO2 generated, assuming NC fuel mix 193.50 774.00 296.70 1290.00
Daily hrs Bulb life operation hrs 3 10,000
Years operation Watts 9.13242 15 60 23 100
Bulb "lifetime", kWh used hrs lifetime 10,000 150 10,000 600 10,000 230 10,000 1,000
CO2 from NC Energy Mix
Fuel Coal Nuclear Petroleum Natural Gas Hydroelectric Other renewables Pumped storage & other total
% mix 60.5 30.8 0.4 2.4 4.2 1.4 0.3 100
Pounds CO2 Pounds CO2 contributed to per kWh proportional 100 kWh mix 2.06 124.63 0.00 0.00 1.97 0.79 1.32 3.17 0.00 0.00 0.00 0.00 0.00 0.00 128.59 pounds CO2/kwH for proportional mix
1.29
Fuel percentages from U.S. Department of Energy State Electricity Profiles 2005 (most recent available). CO2 factor from Energy Star Change a Light, Change the World 2007 Campaign Facts and Assumptions Sheet Petroleum and Natural Gas factors from "Carbon Dioxide Emissions from the Generation of Electric Power in the United States", July 2000, U.S. Dept. of Energy
# of Households in North Carolina Avg Annual U.S. Household Lighting Use, kWh
3,409,840 2007 Energy Star Data 1,950 2007 Energy Star Data Bulb lifetime Energy Savings, kWh 1,534,428,000
based on spreadsheet calculations
based on Energy Star's "NC Fun Facts" figure of up to 172 million kWh annual savings
If every NC household saved replaced one 60-watt standard bulb with one 15-watt Annual Energy CFL: Savings, kWh 168,019,866 Annual NC energy savings will light
Annual NC savings of 172 million kWh will light
86,164 homes for one year 88,205 homes for one year 786,886 homes for one year
Bulb Lifetime NC energy savings will light
based on spreadsheet calculations
If every house in NC replaced one 60w light with a 15-watt light, we would save: million pounds 217 of CO2 a year assuming fuel mix of 60% coal, 31% nuclear etc. $15,323,412 dollars in annual energy costs 18,897 cars a year using Energy Star factor of 11,470 pounds CO2/car/yr
CO2 equivalent to
h annual savings