Max wattage for LED bulbs in new light fittings

[Harry Bloomfield]

therefor saving of £611 so far.
and more importantly just over 1 tonne of CO² saved

the LEDs were £9 each back in Jan 2014, think they are about £3 each now.

I have probably saved even more since swapping to LED's. I bought around 20x 3.5w quality LED's at BHS store closure at 50p each. They put out a surprising amount of light and I used them as my general replacement around the house, where a lot of light wasn't essential, backed up by more powerful CFL lighting sources for when more was needed, with the addition of turning lights off when not needed.

I still have two tungsten lamps, one lighting the under stair cupboard, the second lighting the back door foyer area - neither are normally used. Three florescent tubes in my loft workshop, another lighting the utility, then several modular florescent fittings lighting my garage and workshop.

 

[Munroast]

But you have not considered the CO2 generated by their manufacturer compared with halogens!

do you have some figure so as I can factor them in ?

will need to know CO2 in the production of a GU10 type LED, and also the CO² from the production of a similar bulb of Halogen design. And considering Halogen only last a fraction of the time of a LED then it would not surprise me if one LED lamp produced a great deal less CO² than 4 Halogen.

 

[winston1]

No I don’t have the actual figures.

 

[DetlefSchmitz]

No I don’t have the actual figures.

What a surprise!

 

[endecotp]

But you have not considered the CO2 generated by their manufacturer compared with halogens!

Imagine that every penny of the price that you spend on the LED bulb is used to buy cheap coal to burn.
That gives you an upper bound on the CO2 emissions during manufacture.

Apparently coal costs about $60/tonne (from a quick google). So the £1.50 I just paid for a lamp could have bought about 30 kg of coal, which would have prpduced about 100 kg of CO2.

Compare with the tonne of CO2 that Munroist has estimated as the saving.

Note 100 kg is only an upper bound, the true amount is surely a tiny fraction of that.

 

[JohnW2]

.... As to cost, lets say 14p per kwh and on 4 hours a day .... over 7 years
.... therefor saving of £611 so far. ... And that is just for one room !

Very similar to what I reported above (post #6). Admittedly I assumed 6h per day (but, like you, also assumed 14p/kWh), my kitchen works out at a saving in running cots of about £108/year, hence £756 over 7 years - and, again, 'just for one room' - and, like you, I have had to replace very few of the LEDs over the past several years.

Kind Regards, John

 

[Munroast]

Very similar to what I reported above (post #6). Admittedly I assumed 6h per day (but, like you, also assumed 14p/kWh), my kitchen works out at a saving in running cots of about £108/year, hence £756 over 7 years - and, again, 'just for one room' - and, like you, I have had to replace very few of the LEDs over the past several years.

Kind Regards, John

The one thing that neither of us have accounted for is the heat energy that came off the more traditional type of bulbs, probably for 9 months of the year this heat would have supplemented the heating systems in our homes. Probably not the most cost efficient type of heating, but all that heat energy was inside the home and ultimately our heating systems would have needed to work less.

 

[JohnW2]

The one thing that neither of us have accounted for is the heat energy that came off the more traditional type of bulbs, probably for 9 months of the year this heat would have supplemented the heating systems in our homes. Probably not the most cost efficient type of heating, but all that heat energy was inside the home and ultimately our heating systems would have needed to work less.

Yes, that is a consideration, and something that ericmark here is always making quite an issue out of.

However, I think it is a very trivial consideration in most domestic situations. In any event, even if the heat produced was 'useful' (at some times of year), since electricity is by far the most expensive way of generating heat, one would have done better to use bulbs which produced no heat (hence used much les electricity) and, instead, spend a little more (much less than the electricity would cost) on a little more gas or oil.

... and then, of course, there are usually at least some months of the year during which the additional heat would be 'unwelcome'/unneded, and hence the cost of producing it definitely 'wasted money'.

Kind Regards, John

 

[Harry Bloomfield]

The one thing that neither of us have accounted for is the heat energy that came off the more traditional type of bulbs, probably for 9 months of the year this heat would have supplemented the heating systems in our homes. Probably not the most cost efficient type of heating, but all that heat energy was inside the home and ultimately our heating systems would have needed to work less.

OK, let's think about that one. My gas heat costs me less than 1/4 what electrical heating would cost. My boiler is rated 18Kw and my calculations suggest it needed to burn around 1/50th of the time, to keep the house warm and supply all of our hot water needs - at this time of year (the past weeks figures). So gas heat input around 350w each hour, spread over the 24 hours.

Had I not swapped tungsten for LED, we would have probably been burning around 200w for six hours each evening for lighting, 90% of which is waste heat - versus the maybe 30w of LED I am actually using. In addition to swapping to LED's and somewhat earlier, I swapped 3 CRT TV's for 2 LED and 1 plasma. I swapped the large plasma two years ago for a large LED screen. CRT's were even less efficient than tungsten lighting.

I'll leave it to someone else to derive a conclusion from my figures above, but what I do know, is that despite comfort levels increasing dramatically over the years, my bills have reduced dramatically. £9.56 for gas and £8.94 for electric, for the week, last week, despite all the gadgetry running 24/7 here.

 

[bernardgreen]

The thermal energy, ( radiated infra red ) from incandescent lighting can be detected by human skin and has a therapeutic benefit for the person and their skin.

This is lacking in LED lighting.