Sam Goldwasser wrote:

Cost of 60W incandescent lamp: $0.25 cents.

On what planet is that ?

More like £0.45 here.


Cost of electricity to run a 1000 hour 60W lamp over its life at 10
cents/kWh: $6.

£6

Total cost over life: $6.25.

£6.45

Cost of electricity and lamps to run 60W lamps over 30,000 hours: $187.50.

£193.50


Cost of 60W equivalent CFL + electricity over 30,000 hours assuming it
uses 25 percent of the power of a 60 W incandescent lamp: $22

£ 1.95 for qty 5, 6000 hr Philips bulbs

+ $45

£45

= $67.

£ 46.95


Around here, good quality spiral CFLs with 5,000 to 8,000 hour claimed
lifetimes cost around $5-6 in hardware stores (much less at large home
centers).

£ 0.39 @ Morrisons for Philips.

So £ 193.50 for incandescents vs £ 46.95 for CFLs.

Graham