Estimating global CFL savings
Estimating global CFL savings
The Worldwatch Institute's estimates are based on 15% decay in existing
CFL stock per year and the same amount of light from 15-watt CFLs and
60-watt incandescents. Worldwatch estimates are based on 15-watt CFLs
replacing 60-watt incandescents, used for 4 hours per day, and with an
"average-sized coal fired-power plant" producing 440MW electric
output, operating 80% of the time (80% availability). Global incandescent
sales are estimated at 11.0 billion units in 1999; assume 1000 hours for
an incandescent lamp and 10000 hours for a CFL. Incandescent market estimate
provided to IAEEL and WWI from industry sources. The 1999 CFL market sales
figure (432 million) is decayed by 15% over the year. While the estimate
expresses the savings from installing CFLs instead of incandescents, it
is difficult to determine how many CFLs are literally used in place of
incandescents.
The emission reduction estimates are based on 0.196 metric tons of carbon
and 0.0038 metric tons of sulfur dioxide per 1000 kilowatt hours of electricity
generated in the United States. Electricity consumption and carbon emissions
are taken from US Department of Energy (DOE), Energy Information Administration
1999, Table: "1997 U.S. Electric Information at a Glance," available
on web site: www.eia.doe.gov, retrieved
January 19, 2000.