I have spent alot of time messing around with LED bulbs and for any new build or major refurb i can strongly vouch for the following which I have put into a few bedrooms - the quality and intensity of the light is hard to beat.
responda light - (it is also a Northampton based hi-tech company)

Hi, I am also looking into LED for my summer house the one's I have come across don't seem to be bright enough to light a room, any ideas tried CREELLS web site but they are US based, who are responda light? thanks bevs.

The units are 7w each and they produce a light far in excess of a standard downlight, they are also dimmable (with the right set up)

I have put into a hotel room, 7 of these as downlights provides heaps of light - so its very practical.

url: www.realworlddesigns.co.uk

but I bought mine through the electric centre in Northampton.

hi, i have purchased the system without PIR/sound activation, although I plan on putting it in certain applications with PIR - eg hallways and store rooms

I can confirm that this is a "proper" solution. The light quality is powerful, instant and low energy - and the colour quality is excellent - basically there are only two possible disadvantages -

1. cost - its much higher - but obviously it will pay back quickly
2. lifetime - supposedly 30k hours or 50k hours or whatever - who knows - we can only know how good these things are once they have been in for years. (but I do have a manufacturors 5 year guarantee)

I am not affiliated with the company - although I did tell them I would be interested in buying shares in them!

Terry,

I'm not sure what you mean by not quite there, as far as I am concerned this product is "there", but the cost is around £35+vat for the light and transformer, which is equivalent to probably 1.5 or 2 regular 35/50w halogens, so if you consider the cost of the electrician, then it may actually be a saving on installation (for new build). For slightly more expensive transformers they are dimmable too (with quality dimmers )

i just realised my post before was not clear, each bulb puts out alot more light than a regular GU10 halogen - i dont have a light meter but you could safely assume you could replace say 3 halogens with 2 of these products, so thats what I meant by making savings with a sparky. also as cwatters mentioned you can actually DIY these if you have a plug in power source- (another saving)
so even though it seems expensive at first glance, it actually isnt.

Can see these as a downlighter replacement, but still not sure why much better than a CFL on a central pendant?

J

James - in short they are not.

LEDs are great - I love them, but only the best current LEDs compete with CFLs on efficiency, and nothing outside the lab competes with flourescent tubes. I have recently found that actual CFLs, especially the lower-power ones, are less efficient than I had previously understood so CFLs are 40-100 lumens/watt, with average being say 55. LEDs are 10-80, and I have no idea what you actually get out of typical units currently on sale after allowing for PSU losses.

So so long as you are getting 'latest' LEDs then they may well be as good as CFLs, and might even be a bit better. They do have other advantages too, like instant start, perfect dimability and closer-to-daylight colour temps, but then they are currently much more expensive, and some don't like the colours.

So yes, much better than halogens, but worse than tubes and 'similar' to CFLs (between 5 times worse and nearly twice as good depending).

Sadly very few suppliers tell you how many lumens/watt you are actually getting so it's very hard to choose stuff at the moment.

I found some efficiency data. these are 44 Lumens/watt, so about the same as a 7 or 9W CFL.

More data on the Responalight series found here..

http://www.led-lightbulbs.co.uk/images/pdf/EX-7WW-36_datasheet.pdf
and
http://www.mgc-lamps.com/documents/Respondalight.pdf


Anyway the above says "Up to 500 lumen output" which I contrast with a typical 35W halogen downlight (around 600L) and a 50W halogen (900L). I know there are issues with quoting light output in Lumens but it's hard finding any tech data. The Respondalight web site has a beam intensity profile drawing but I couldn't find a similar drawing for a halogen downlight. The Philips website in particulare seems free of technical data these days.

So not too bad.

hotelRefurber
I am looking for lighting for my kitchen (c4m x 4m), and had planned to use 7 or 8 spotlights such as halogens. Do you think these Respondalights would be an adequate replacement? I have been keen to use LEDs if possible, but until now I have not found anything which I could guarantee would be suitable. (Also not keen to invest in something without having seen it in action somewhere!).

Are these a suitable light to link to some sort of pv set up,?am trying to understand how pv could be used.

Ive used standard fittings with 2W cfl from megaman - take a bit to warm up but good output per watt.

The LED bulbs are almost good enough.

I have used 4 of the GU10 variety in a kitchen for about 6 months. They run off mains 240V. The brightness is not quite there yet - my Missus is not happy. Where they win on price compared to halogens is on lifetime. 30000 hours compared to 2000 hours. So they are already cheaper when you include reduced elec consumption and longevity.

The other LED variety run off 12V. They easily include the 12V to current converter to regulate them. The electronic solution for this is mass market already as it is used in cell phones etc. There would be an excellent market for 12V lighting circuits, it already exists in caravans. However my understanding is the UK government has already moved to screw this up by including low voltage lighting in with the electrical regulations.

Government is living proof of entrapy.

Hotelrefurber,
how many units are on in the above picture
tom