One light bulb Conventional (incandescent) light bulb Compact florescent Light bulb (CFL) Saving Assumptions
Cost of bulbs  $                 4.00  $                   1.50  $           2.50 1 light, ~3hrs/day, 1,000 hr/year, 10,000 hours, over 10 years.
Ten incand. Last 1,000hr $0.40 each
One CFL lasts 10,000hr $1.50 each
Cost of electricity  $               60.00  $                 13.00  $         47.00 60W for incand., 13W CFL
10,000hr, $0.10 per kW/hr
Cost of repairing environmental damage  $                 3.64  $                   0.79  $           2.85 Incand. uses 600kW.hr, emits 0.36 tons carbon, causing $3.64 damage
CFL uses 130 kW.hr, emits 0.08 tons carbon, causing $0.79 damage
TOTAL  $              67.64  $                15.29  $         52.35                  
1600 Sudbury seniors assuming 10 light bulbs each Conventional (incandescent) light bulb Compact florescent Light bulb (CFL) Saving Assumptions
Cost of bulbs  $             64,000  $               24,000  $        40,000 Same as above, except 1600 Sudbury seniors, 10 light bulbs each
Cost of electricity  $           960,000  $             208,000  $      752,000
Cost of repairing environmental damage  $             58,240  $               12,640  $        45,600
TOTAL  $        1,082,240  $            244,640  $     837,600