A kitchen with two ceiling mounted fittings each containing four 50 Watt Halogens, that are on for an average of six hours a day.
Running Costs - 8 x 50 Watt bulbs for 6 hours a day over a year (876 kWh @ 15p per kWh inc VAT) = £131.40
Replacement Bulb costs - (each Halogen bulb pops after 1000 hours) 2190 hours in a year means 17.5 replacements at £4 each = £70
Total cost for Halogen lighting = £201.40 for the first year, £402.80 after the second year, £604.20 after three years, etc.
OK, lets replace all these power-hungry halogens with some top of the range Bell Intensity Warm White LED Bulbs (of course you can replace them one at a time to spread the initial cost)
Running Costs - 8 x 5 Watt bulbs for 6 hours a day over a year (87.6 kWh @ 15p per kWh inc VAT) = £13.14
Replacement bulb costs - 8 x £28.95 (inc VAT) = £231.60
Total cost for LED lighting = £244.74 for the first year, £257.88 after the second year, £271.02 after three years, etc.
So, by the end of the second year we have saved a total of £144.92 on lighting and will continue to save £188.26 every following year (that's a saving of 90%).
A word about Lamp life
LED
lamp life of 50,000 hours = 6 hours a day for over 22 years.
LED lamp life of 30,000 hours = 6 hours a day for 16 years.
Halogen lamp life of 1000 hours = 6 hours a day for under 5.5 months.
