ledl:led_lighting

Differences

This shows you the differences between two versions of the page.

Link to this comparison view

Both sides previous revision Previous revision
ledl:led_lighting [2026/03/12 11:38] – Dave Darbyledl:led_lighting [2026/03/26 18:33] (current) – external edit 127.0.0.1
Line 1: Line 1:
-# LED lighting+This topic is part of [[gt:power|Power & heating]]. 
 +====== LED lighting ======
  
  
Line 10: Line 11:
  
  
-## What is LED lighting?+===== What is LED lighting? =====
  
 LEDs (light-emitting diodes) are semi-conductors that emit light via [electroluminescence](https://en.wikipedia.org/wiki/Electroluminescence). An electric current is passed through the semi-conductor, whose electrons are agitated and emit light in the form of photons. This doesn't involve very much heat (and the heat that is generated is dissipated), so LEDs are cool to the touch, even when illuminated. LED lighting differs from other light sources in the following ways: LEDs (light-emitting diodes) are semi-conductors that emit light via [electroluminescence](https://en.wikipedia.org/wiki/Electroluminescence). An electric current is passed through the semi-conductor, whose electrons are agitated and emit light in the form of photons. This doesn't involve very much heat (and the heat that is generated is dissipated), so LEDs are cool to the touch, even when illuminated. LED lighting differs from other light sources in the following ways:
Line 32: Line 33:
 LED lighting takes energy saving a step further (see below). LED lighting takes energy saving a step further (see below).
  
-### History+==== History ====
  
 Light emission from semi-conductors had been known about since the turn of the 20th century, but it wasn't until the 1960s that the first visible red LED was developed. Other coloured LED lights were developed over the following years but the level of illumination that they provided was fairly low. In the 1970s, brighter LEDs were developed and used in fibre optics. LEDs began to be used in displays, but you needed thousands of them gathered together to make a difference to the surrounding light. This continued to be an issue until the 21st century, when ways to produce more light from a single bulb were found. Light emission from semi-conductors had been known about since the turn of the 20th century, but it wasn't until the 1960s that the first visible red LED was developed. Other coloured LED lights were developed over the following years but the level of illumination that they provided was fairly low. In the 1970s, brighter LEDs were developed and used in fibre optics. LEDs began to be used in displays, but you needed thousands of them gathered together to make a difference to the surrounding light. This continued to be an issue until the 21st century, when ways to produce more light from a single bulb were found.
Line 59: Line 60:
  
  
-## What are the benefits of LED lighting?+===== What are the benefits of LED lighting? =====
  
-### Personal: effectiveness+==== Personal: effectiveness ====
  
 Compared to CFL bulbs, LEDs give out their light immediately which means you don’t get that period when they are warming up before you get full illumination. Compared to CFL bulbs, LEDs give out their light immediately which means you don’t get that period when they are warming up before you get full illumination.
Line 80: Line 81:
 </WRAP> </WRAP>
  
-### Personal: cost+==== Personal: cost ====
  
 The cost of LEDs has always been an issue (you can expect to pay about £5-10 for a single bulb on average) but prices are falling and, if you take into account their longevity and low energy usage, they're now more efficient and more cost-effective that tungsten and CFL or fluorescent bulbs, despite the initial outlay. If you buy an LED bulb for £10 and it lasts 5 times as long as a CFL bulb which costs £2, you're already on a par. Add in the electricity cost savings and you can see the overall benefit. According to GMI Energy, replacing 40 58W fluorescent strip lights with 40 20W LED lights can save in excess of £1,300 a year on utility bills for a business. The cost of LEDs has always been an issue (you can expect to pay about £5-10 for a single bulb on average) but prices are falling and, if you take into account their longevity and low energy usage, they're now more efficient and more cost-effective that tungsten and CFL or fluorescent bulbs, despite the initial outlay. If you buy an LED bulb for £10 and it lasts 5 times as long as a CFL bulb which costs £2, you're already on a par. Add in the electricity cost savings and you can see the overall benefit. According to GMI Energy, replacing 40 58W fluorescent strip lights with 40 20W LED lights can save in excess of £1,300 a year on utility bills for a business.
Line 101: Line 102:
 </WRAP> </WRAP>
  
-### Environmental+==== Environmental ====
  
 LED lights use less electricity – you can get a 90% reduction if you are replacing traditional filament bulbs and up to 30% if you are replacing more modern CFL or fluorescent ones. LED lights use less electricity – you can get a 90% reduction if you are replacing traditional filament bulbs and up to 30% if you are replacing more modern CFL or fluorescent ones.
Line 122: Line 123:
 </WRAP> </WRAP>
  
-### Decentralising power away from corporations / community building+==== Decentralising power away from corporations / community building ====
  
 This is a tricky one, as LEDs are made and sold by corporations, and so until co-operatives start to make them, you have to support corporations if you use LEDs. However, as they use much less electricity, that means that you need to pay less to energy corporations. This is a tricky one, as LEDs are made and sold by corporations, and so until co-operatives start to make them, you have to support corporations if you use LEDs. However, as they use much less electricity, that means that you need to pay less to energy corporations.
Line 130: Line 131:
  
  
-## What can I do?+===== What can I do? =====
  
-### Fittings+==== Fittings ====
  
 You don't have to change your fittings - LEDs come in screw fitting and bayonet as standard, for ceiling, wall or desk lights. More recently, excellent LED strip lights have also been developed. If you're replacing the kind of halogen bulbs with two little pins in the back, you can find LEDs to replace them too. They might be low-voltage bulbs though (for off-grid / battery systems) - so talk it through with the retailer first if you're unsure. Changing fluorescent strips can be more of an issue, and choosing the right ones needs a little more thought. Some LED strip lights are made to fit into existing fluorescent tube fittings, but others will need an electrician to do a bit of work first - again, talk to your retailer. You don't have to change your fittings - LEDs come in screw fitting and bayonet as standard, for ceiling, wall or desk lights. More recently, excellent LED strip lights have also been developed. If you're replacing the kind of halogen bulbs with two little pins in the back, you can find LEDs to replace them too. They might be low-voltage bulbs though (for off-grid / battery systems) - so talk it through with the retailer first if you're unsure. Changing fluorescent strips can be more of an issue, and choosing the right ones needs a little more thought. Some LED strip lights are made to fit into existing fluorescent tube fittings, but others will need an electrician to do a bit of work first - again, talk to your retailer.
Line 140: Line 141:
 {{ http://lowimpactorg.onyx-sites.io/wp-content/uploads/office-1.jpg }} {{ http://lowimpactorg.onyx-sites.io/wp-content/uploads/office-1.jpg }}
  
-### Brightness+==== Brightness ====
  
 Look at lumens for brightness, not watts. Wattage tells you how much energy the bulb is using, not its brightness. For example, a typical 60-watt incandescent bulb will give 800 lumens, but an LED light will give the same brightness for around 10 watts. A 100-watt incandescent bulb and a 25-watt LED will both give around 1600 lumens. Look at lumens for brightness, not watts. Wattage tells you how much energy the bulb is using, not its brightness. For example, a typical 60-watt incandescent bulb will give 800 lumens, but an LED light will give the same brightness for around 10 watts. A 100-watt incandescent bulb and a 25-watt LED will both give around 1600 lumens.
Line 157: Line 158:
 </WRAP> </WRAP>
  
-### Buying LEDs+==== Buying LEDs ====
  
 LED lighting is now widely available across the UK. You can also buy online but if you want to achieve the energy and cost savings, it's essential to buy quality. Make sure you read reviews and choose a reputable supplier or brand before you settle on a particular product. In the end, it’s worth paying a bit extra for a bulb that actually does the job you want it to do. LED lighting is now widely available across the UK. You can also buy online but if you want to achieve the energy and cost savings, it's essential to buy quality. Make sure you read reviews and choose a reputable supplier or brand before you settle on a particular product. In the end, it’s worth paying a bit extra for a bulb that actually does the job you want it to do.
Line 177: Line 178:
 </figure> </figure>
 </WRAP> </WRAP>
-### Installing and using LEDs+==== Installing and using LEDs ====
  
 LEDs do actually produce some heat, but they dissipate it so that the bulb stays cool. This means that LEDs might not be ideal for enclosed spaces, where they might not be able to dissipate the heat. LEDs do actually produce some heat, but they dissipate it so that the bulb stays cool. This means that LEDs might not be ideal for enclosed spaces, where they might not be able to dissipate the heat.
Line 186: Line 187:
  
  
-## Further resources+===== Forum ===== 
 + 
 +This topic belongs to the section [[gt:power|Power & heating]]. You can ask questions or add information on the corresponding [Forum section](https://forum.growingthecommons.org/t/power). 
 + 
 +===== Further resources =====
  
 - [Wikipedia](wp>History of the LED): History of the LED - [Wikipedia](wp>History of the LED): History of the LED
Line 200: Line 205:
  
  
-## Related topics+===== Related topics =====
  
-- [Energy saving](https://knowledge.growingthecommons.org/doku.php/ensa/energy_saving) +- [Energy saving](ensa:energy_saving) 
-- [Low-impact energy](https://knowledge.growingthecommons.org/doku.php/lien/energy) +- [Low-impact energy](lien:energy) 
-- [Candlemaking](https://knowledge.growingthecommons.org/doku.php/cndl/candlemaking)+- [Candlemaking](cndl:candlemaking)
  
-## Specialist curators of this topic+===== Specialist curators of this topic =====
  
  • ledl/led_lighting.1773315499.txt.gz
  • Last modified: 2026/03/12 11:38
  • by Dave Darby