Below are the assumptions and variables that were used for this calculator:
| Business Variables: | ||
| BES Average Hours Per Day Use | 9.589 | |
| BES weighted avg VT $/kWh | $0.115 | |
| BES Hours Per Year Per CFL | 3,500 | |
| BES KWH Used Incandescent Per Year | 262.5 | |
| BES KWH Used Per CFL Per Year | 69.9997 | |
| BES KWH Saved Per Year Per CFL | 192.50 | |
| BES Lifetime CFL KWH Savings | 660 | |
| BES CFL Life (in Years) | 3.43 | Based on Bulb Life Divided by Hours Per year of use |
| BES CFL BULB Life (in Hours) | 12000 | |
| Incandescent Bulb Life | 1000 | |
| typical Purchase cost of incandescent | $0.50 | |
| typical Purchase cost of CFL | $5.00 | |
| BES CFL Cost 1st Year | $1.46 | |
| BES Incandescent 1st year cost | $1.75 | |
| Incandescent Lifetime (CFL Bulb Life) cost | $4.00 | |
| BES Days Used | 365 | |
| Residential Variables | ||
| RES Average Hours Per Day Use | 3.4 | |
| RES weighted avg VT $/kWh | $0.133 | |
| RES Hours Per Year Per CFL | 1,241 | |
| RES KWH Used Incandescent Per Year | 93.075 | |
| RES KWH Used Per CFL Per Year | 24.82 | |
| RES KWH Saved Per Year Per CFL | 68.255 | |
| RES Lifetime CFL KWH Savings | 440 | |
| RES CFL Life (in Years) | 6.44 | Based on Bulb Life Divided by Hours Per year of use |
| RES CFL BULB Life (in Hours) | 8000 | |
| Incandescent Bulb Life | 1000 | |
| typical Purchase cost of incandescent | $0.50 | |
| typical Purchase cost of CFL | $5.00 | |
| RES CFL Cost 1st Year | $0.78 | |
| RES Incandescent 1st year cost | $0.62 | |
| Incandescent Lifetime (CFL Bulb Life) cost | $0.00 | |
| RES Days Used | 365 | |
| Lifetime Savings Equivalents: | ||
| 1 kWh = tons of coal | 0.0001644 | |
| lbs CO2 per kWh electricity generated | 1.260 | Source: Avoided Energy Supply Costs in New England: 2007 FINAL REPORT |
| average annual household electric usage in Vermont (KWH) | 7000 |
