energy saving light bulbs

wellsie82

Morning everyone,

For some years now we've used energy saving bulbs in the standard lights we have (the bog standard screw-in 40-60 watt things) but it's crossed my mind that 2-3 rooms in our house have a light fitting which requires up to 5 GU10 style halogen lights

The bulbs we currently use in these are 35-40watt and on the fitting itself it says "max 35w"

I've been looking online today to see whether there is such a thing as an energy efficient bulb to replace these as I imagine the halogen ones aren't the cheapest to run

I've come across these http://www.energybulbs.co.uk/products/Spotlights/GU10+Spotlights/Decor+Eco+Halogen+GU10+20W%3D35W+-+10+PACK/547816439 but im wondering whether they'll be strong enough in terms of light output to replace what we currently have. They say "Equivalent To 35w" but the actual wattage is 20. Does this mean we'll be paying for 20w but getting the equivalent light output of 35w?

The other question is whether it's worth replacing them at an outlay of some £30?

sunshine54

if the light output is the same you will be saving 15w. over the lifetime of the bulb (2000hrs) you will save 15x2000= 30000w= 30kw
at a cost of £30 you will spend £1 to save 1kw/h off your bill (about 8p)

wellsie82

sunshine54 wrote: »

at a cost of £30 you will spend £1 to save 1kw/h off your bill (about 8p)

so its not worth it really - is that the gist of it?

ddoris

The bulbs you link to will save £3 each if they last rated 2000hrs -assume 10p/kwh
A 2w led at £10 each will save £99 over it's rated 30000hrs ,not dimmable. Tho the 3w led says equiv to only 25w and is £17
http://www.lightbulbs-direct.com/product/3430/gu10-led-3w-warm-white/

These seem a better choice 'til led fall in price - http://www.energybulbs.co.uk/products/3560407181 -not dimmable but each would save £18 over it's life. They do 11 and 13 w as well £5.95 and £6.45 -tempted myself - the watt limits are regards heat so all lower watt consumption should be fine. I can't vouch how bright any of these look tho' .

edit -not clear how long you will keep saving for in post #2 -eg if you claim it will save 8p/hr then it pays for itself in under 13 hrs??? An excellent payback!

notbritishgas

No experience with energy saving GU10's, but if you believe what they say then yes you get the equivalent light of a 35w light for 20w of power, saving about 50%.
However I think a better alternative would be to consider LED GU10's. These typically consume about 3w of power for your light output so the saving is greater but the initial cost may be a bit higher.
Google LED GU10 to see what is available.

Edit: Cor blimey, there were no posts when I started typing.

wellsie82

thanks for all the replies today guys - if anything im more confused lol

i like the dimmer feature on the current bulbs so i think id like to keep this on any replacements, i think i'll try and have a look online for a calculator type tool which can work out costs of running the current ones vs potential new ones

djohn2002uk

notbritishgas wrote: »

Edit: Cor blimey, there were no posts when I started typing.

Perhaps a typing course might help. :cool:

wellsie82

interesting, ive found a calculator at http://www.lightbulbs-direct.com/article/energy-saving/

now ive put in as follows: 35 watts, 2 hours per day, 5 bulbs, cost of 23p which comes in at £29.38 per year. the annual cost at 7watts is £5.88

now the wattage of the original link i posted was 20 so to get 7watts up to 20 im multiplying by 2.9. if i multiply £5.88 against 2.9 i get £17.05 which is sacing of £12.33 per year

assuming ive worked this out correctly, this means that in two years i would of saved nearly £25 (nearly the cost of the intial pack of ten bulbs), and this is notwithstanding the two other fittings we have which contain 2-4 bulbs per fitting that i have excluded from my workings out

spakkker

If you have a fitting with 4 x35W bulbs it will use140w (1000w for an hour is 1 unit, kw/hr, say cost 10p/unit) which will cost nearly 10p if on for 7hrs -7x140=980w (nearly 1 unit, 1000w)
If you use 4 led bulbs of 3w each you are only going to use 12w ,1 unit of leccy is 1000w so you can run 4 leds at 12w for 1000/12 =83 hours for 10p. 83 hours with 4x35w would use 83x140= 11620w , 11.6 units or £1.16 hence saving a quid every 83 hours use.

edit You seem to have got it - just remember the rated lifetime of the bulbs as well. Leccy isn't getting any cheaper either.

horace_2

Don`t forget the clean up costs for a `chemical spillage` if you break the outer glass.

This makes any energy saving a total nonsense.

globalds

If you want to try an LED GU10 then have a look at the ones in Lidl's supermarket.

They are equivalent to a normal 25w light( 3w LED). They are very similar in colour and are only £5.00 each so if they are not to your taste it is not a huge pile wasted.

I tried 4 as replacements in a small bathroom and they are not bad.