Shedding Light On LEDs

Over the last year or so LED lighting has come on in leaps and bounds. I used to associate LEDs with cheap novelty products, short range torches and low voltage Christmas lights, but not anymore. My personal eureka moment came when I fitted a LED replacement bulb in my Maglight torch last year and promptly temporarily blinded myself.

Since then I have gone on to change all the bulbs in my camper van to LED which now means I can run my lighting from the battery for days instead of just hours. This was so successful that I decided to experiment with LED replacement bulbs in my house as well.

What Is An LED Bulb?
LED stands for Light Emitting Diode and until fairly recently you only found them in displays such as digital alarm clocks and some television and computer screens. LEDs only emit light straight in front of them, which coupled with their low brightness made them unlikely candidates for general lighting applications. However, new manufacturing techniques have conquered the brightness problem almost too well (do not look straight into one) and clever arrangements of the LEDs and the use of diffusers have largely solved the directional problems.

LEDs can create almost any colour so you can have red, blue, green or even colour changing bulbs, but by far the most popular are white of course. They generally come in two shades, bright white which I find a bit harsh, though some people like them for kitchens and bathrooms, and warm white which is nearer to the colour temperature of traditional bulbs. Daylight options are also becoming available though I haven't tried these yet.

Saving Money
Replacing your traditional incandescent bulbs with equivalent brightness compact fluorescent bulbs (CFLs), which most of us have already done, saved about £3 per year per bulb or £50 over the lifetime of the bulb. Switching to LEDs however can save you a lot more as the higher initial cost is more than off set by their long life and low running costs.

Saving The Planet
LEDs have no IR (infrared) or UV (ultra-violet) emissions and unlike compact fluorescent contain no dangerous chemicals or atmospheric pollutants. The directional quality of LEDs makes them less light polluting as well.

They have a service life of up to 25 years and are very efficient in the way they use electricity, turning 80% of the power into light. This is a great deal better than a conventional bulb that, at best, only manages to convert 20%, giving off the remaining 80% as heat.

It is estimated that around 20% of the world's energy is used in lighting and that this would reduce to a mere 4% if we all switched to LEDs. If this is true then perhaps we don't need nuclear power stations, which supply about 18% in the UK, but to simply change our light bulbs instead.

Calculating Brightness
One of the biggest stumbling blocks to successfully changing from incandescent, compact fluorescent or halogen to LED bulbs is getting your head round this new range of wattages. Most of us have a good idea how bright a 60W incandescent light bulb is and have probably long ago replaced most of them with 11W compact fluorescents but there the story ends because LEDs can have quite different brightnesses depending on the colour of the light and how they are configured and housed. So instead of relying on Watts we need to compare Lumens.

Buying Sensibly
The rrp of LED bulbs are usually set ridiculously high but they can be found at very substantial discounts on the internet and increasingly in stores as well. The important thing is to only buy makes that you trust and preferably from retailers with a good returns policy (a certain amount of trial and error is no bad thing). Do not be tempted to buy cheap copies: if the price seems too good to be true, it probably is. I made this mistake initially but learnt my lesson when one of the bulbs burnt out within hours. Personally, I have used and trust Aurora, Lumilife and Philips, but any main brand name should be fine.

Conclusion
The replacement of conventional bulbs with LEDs has led to better controlled and nicer lighting. Generally I am very pleased with my LED lighting and consider it a worthwhile investment which should more than pay for itself both financially and environmentally over the next few years. I hope you have found this article useful and are inspired to follow where we have LED!

John Adams is Creative Director at Permanent Publications and writes occasional technology articles related to the ecorenovation of his home. 

The fully illustrated version of this article which also includes;12 Volt LEDs in Practice, 240 Volt LEDs in Practice, Tube Lights & CFL Fittings, Controls, Key Benefits of LED Bulbs, Lumens Table and a Cost Comparison Table, appears in Permaculture magazine No79, Spring 2014.