Let there be light!

[ppppenguin]

We all need decent lighting so here are a few odd thoughts.

CFLs are dead, or very nearly so. Hooray!

If you really still need a real filament light bulb for any reason then the halogens work well. the 105W types give a LOT of light, rather like an old fashioned 150W bulb.

But for most purposes the mighty LED wins. I've been using some of these recently. they give a very nice diffuse light. There larger versions too which I haven't tried. Very slim, but be aware that the little PSU needs to live somewhere.
http://www.toolstation.com/shop/Lighting...ght/p56573

These MR16 LEDs give a lot of light, easily a match for 50W halogens. but watch out for the MINIMUM ratings of electronic 12V transformers. If not adequately loaded you'll get flicker.
http://www.toolstation.com/shop/Lighting...amp/p79583

Inspired by Brian Cuff I have one of these above my bench. Oodles of diffuse, shadow-free light. CHeaper now then when I bought mine.
https://www.tlc-direct.co.uk/Products/LTSP50WW.html

These have an integral driver and weren't available when I bought mine: https://www.tlc-direct.co.uk/Products/LTSP40WW.html

The 1520 lumen LED bulbs you can get for under £10 in various palces are a good replacement for 100W GLS.

Poundland LEDs are great for many smaller applications. At the Dulwich Museum I've fitted dozens of them in the TV display and Droitwich rooms.

Some LEDs are dimmable but you usually need a trailing edge dimmer such as this. Again most dimmers have a MINIMUM load requirement and so work badly with LEDs. Trailing edge dimmers are also nice and quiet, no audible buzz.
http://www.screwfix.com/p/varilight-trai...w-va/94816

[Refugee]

Those 595mm squares look interesting. I have a place where they can replace an old tube strip-light.

[ppppenguin]

The panels are designed to be a drop-in replacement for the fluorescents used in suspended ceilings. Used more and more in shops, offices etc, they give a nicer light than the old florries and for a lower cost of ownership. For a commercial user they use less power for more light and don't ned regular relamping. For the most part in a shop etc they should last between major refits. For my lab I simply used 4 little angle brackets to hold it to the ceiling. You can get frames for surface mounting or do some DIY carpentry for a neater result.

There are LED replacements available for various other fittings too. There are tubular ones that fit directly into fluorescents though it's better to choose the type that needs you to bypass the ballast. Also for PL, Double-D etc. I can now see no reason to use any fluorescent lamps of any kind, whether conventional or compact. the only exception might be if you're stuck with an odd size historic fluorescent fitting (3 foot or 8 foot) and can't repalce the fitting. Even then, the older T12 tubes are now harder to get.

[Craig]

Here's an interesting conundrum:

Mercury batteries have disappeared because of the toxicity of mercury (but totally ignored that it is used in fluorescent strip lighting and CFL's, and in mercury amalgam tooth fillings)
Lead-free solder and unleaded petrol because of the toxicity of lead (but what about car batteries?)
NiCd batteries on the way out or dead because of the toxicity of cadmium

But - many LED's are based on arsenic compounds (like gallium arsenide). And $30Bn worth of them were manufactured in 2016. And yet there is hardly any information out there about the toxic burden that will end up in landfill.

Global production of arsenic is dominated by China (75% of global output), and is currently about 40,000 tons per annum globally, the majority of that ending up in LED's and high speed analogue IC's based on GaAs, and hence found in every mobile phone. Given the global love of technology, all that ends up in landfills. Yet there seems to be no consideration of the long-term implications of that. Or at least noone is owning up to it publically, yet.

[ppppenguin]

Life is hazardous. Whether it's arsenic or tigers. We have to accept a sensible balance between utility and safety.

The amount of mercury in fluorescents was pretty small, probably a lot less than the amount released from the coal burning power stations that powered them. Commercial quantities of florries should have been recycled properly. Dentists in the UK (and likely elsewhere in the 1st world) have to dispose of old fillings properly. I believe that crematoria are significant source of mercury pollution. Composite resin fillings are rather better than amalgam.

NiCd batteries were superceded by NiMH as much for better performance as lower toxicity.

Lead from car batteries is largely recycled, it helps here that the supply chain can readily act as a return chain. Car batteries also contain significant amounts of arsenic.

There's a little online about arsenic in e-waste: https://sites.google.com/site/dukeewaste/arsenic http://ewasteguide.info/hazardous-substances
Whether the electronics waste stream is a significant cause of arsenic pollution is another question. Mining the stuff is certainly nasty.

[pwdrive]

We used to hit a lot of arsenic when drilling and blasting for tin down here, it had a distinctive smell when the drill hit it, Devon Great Consols was the largest producer back in the day, William Morris was a director of that company for a while, the remains of some of the arsenic calciners, labyrinths and stacks still survive down here, originally it was considered as a waste product but it eventually found a market in controlling the Boll Weevil in the cotton plantations etc.

Lawrence.

[Craig]

Arsenic compounds used to sublime in the chimneys from Tin calciners, and small children were sent up the chimney with a brush to clean off the toxic soot, in the 18th and early 19th centuries.

[Craig]

Incidentally - I'm a firm believer in LEDs for domestic lighting. We've been going in that direction for several years now in our house. And the latest generation of cars use LED's for the headlamps.

All I'm saying is that there is an unexpected consequence of this in toxic waste.

[Terry]

I bought some LED strip lights from Lidl recently for lighting the kitchen worktop. There are two cabinets in a corner, so it is especially dark when you stand there.

They are mains driven and came with short male/female link leads so that they can be daisy chained, up to a maximum of 10, I believe. I think, from memory, that they cost £10 each.

I only needed two, one under each smallish cabinet. They are superb! The housings allow the LEDs to be swivelled so they are positioned to give beautiful even light coverage from the wall to the worktop edge.

Management are delighted!

[ppppenguin]

There are some rubbish LEDs around. Typically overclaiming on brightness and/or poor colour rendering. In fact even the good ones aren't quite perfect on colour rendering so some very critical applications may still need halogens.

Some LEDs tend to run hot and will have short lives but the overall trend is better and cheaper.