Sign up for low energy lightbulbs

My friend Steve is 15 signatures short of his pledge to replace all the bulbs in his home with low-energy equivalents. I converted the last of our rooms to low energy on Tuesday by replacing the dimmer swift and swapping out the 40-watt bulbs for three 5-watt candle style bulbs at a total cost of £18, including the Georgian brass switch. The 5-watt bulbs are the equivalent of 25 watts, but if anything the room is brighter now (probably because I only had two working 40-watt bulbs in there). As for the £18 cost, I'll soon recoup that in lower electricity bills. Here's how the saving will work out:

My RSPB Energy electricity supplier charges 8.89p per unit. One unit of electricity is equal to 1,000 watts per hour. We spend three hours in the lounge in the evening - 80 watts x3 = 240 watts per night, so a conservative estimate is that those lights were generating two units (17.8p) of electricity a week. Multiply that by 52 and those lights cost £8.85 a year. Start adding up the rooms of your home, and the cost soon shoots up. By replacing those bulbs as I've done, I've reduced the amount consumed by over 80%, so now my cost is just £1.66 a year, a saving of over £7 - and that's just one room. That means it takes around 18 months to recoup the cost of the bulbs (£4 each), and after that they're making money. As they have a working life of at least five years, you do the maths.

By the way, if anyone wants a Georgian brass-style dimmer switch...

To sign Steve's pledge, click here.