12-10-2013, 10:40 AM
Our house and neighbouring houses have four R80 downlighters in the kitchen, fitted by the builder 22 years ago, in which we use 60 Watt spotlight bulbs. A neighbour has fitted CFLs and they take an age to warm up - hopeless if popping in and out of the kitchen as they never come to full brightness before they're switched off each time, so whereas we switch our lights off when we leave the kitchen, he leaves his on all the time. Hence, CFLs are a dead loss, as they are in other locations where lights are often used for short periods - bathrooms, toilets, store rooms etc, where there is little saving to be made anyway.
The LED ones at the link Jeremy provided look appealing, but the savings seem to be based on office use - not in a domestic kitchen as the savings assume 8 Hrs a day, 365 days a year. (I doubt that many householders leave kitchen lights on eight Hrs a day, 365 days a year). Our kitchen gets little natural light so the lights are often on when we're in there, but we don't live in the kitchen and spend a lot of time each week away from home. I'd estimate that at the very most, we have the kitchen lights on an average of four hours a day for six months and two hours a day for six months - an average of 3 Hrs a day over the year, which would be an upper limit. Hence, that would be 3Hrs x 365 days = 1,095 Hrs a year. The present four lights consume 240 Watts in contrast to four LED lights at 10 Watts each, so each hour in use of LED lights would save 200 Watts, so x 1095 = 219 kW a year saving. Taking the 16p per KW used on the LED light website that equates to a saving of £35.00 a year for all four lights at the very most - about half of the saving of the example on the website of £18.30/Yr per fitting - £73.20 for four.
The cost of four fittings would be 4 x £26.00 and I'd need four bezels @ £3.25 each due to the present holes in the plasterboard being larger than the new fittings, so that's £117 total + VAT £23.40 = £140.40. £35.00 a year saving = four year payback, assuming we don't move house. In our case the cost/benefit case would be so marginal as to not be worth the effort, notwithstanding the fact that we have eight spare 60Watt R80 bulbs which will last us at least two years. (I'm not of course suggesting that our situation is typical, but they assume that I'd do such work on a DIY basis - were an electrician to be employed, the payback period would probably be about a decade).
(The website boasts that the fittings are judged to be 'the lighting project of the year' but doesn't say who awarded that accolade, or how many other similar fittings it was compared with).
The LED ones at the link Jeremy provided look appealing, but the savings seem to be based on office use - not in a domestic kitchen as the savings assume 8 Hrs a day, 365 days a year. (I doubt that many householders leave kitchen lights on eight Hrs a day, 365 days a year). Our kitchen gets little natural light so the lights are often on when we're in there, but we don't live in the kitchen and spend a lot of time each week away from home. I'd estimate that at the very most, we have the kitchen lights on an average of four hours a day for six months and two hours a day for six months - an average of 3 Hrs a day over the year, which would be an upper limit. Hence, that would be 3Hrs x 365 days = 1,095 Hrs a year. The present four lights consume 240 Watts in contrast to four LED lights at 10 Watts each, so each hour in use of LED lights would save 200 Watts, so x 1095 = 219 kW a year saving. Taking the 16p per KW used on the LED light website that equates to a saving of £35.00 a year for all four lights at the very most - about half of the saving of the example on the website of £18.30/Yr per fitting - £73.20 for four.
The cost of four fittings would be 4 x £26.00 and I'd need four bezels @ £3.25 each due to the present holes in the plasterboard being larger than the new fittings, so that's £117 total + VAT £23.40 = £140.40. £35.00 a year saving = four year payback, assuming we don't move house. In our case the cost/benefit case would be so marginal as to not be worth the effort, notwithstanding the fact that we have eight spare 60Watt R80 bulbs which will last us at least two years. (I'm not of course suggesting that our situation is typical, but they assume that I'd do such work on a DIY basis - were an electrician to be employed, the payback period would probably be about a decade).
(The website boasts that the fittings are judged to be 'the lighting project of the year' but doesn't say who awarded that accolade, or how many other similar fittings it was compared with).
Regards, David.
BVWS Member.
G-QRP Club Member 1339.
'I'm in my own little world, but I'm happy, and they know me here'
BVWS Member.
G-QRP Club Member 1339.
'I'm in my own little world, but I'm happy, and they know me here'
