LEDs will slash energy use for lighting by 95% | RenewEconomy

LEDs will slash energy use for lighting by 95%

LEDs will slash energy use for lighting by 95%, delivering huge savings to consumers but adding another ingredient to the death spiral for utilities.


Efficient LED lights are appearing more and more in homes, businesses and industry. Today, LEDs (Light Emitting Diodes) use about 85% less electricity than a conventional lighting source such as an incandescent bulb. They may soon use even less.

ledThis is a significant reduction. Around 19% of the world’s electricity demand is used for lighting; compared to just 3% goes to smelting aluminium – although in Australia we only use about 12% of our electricity for lighting and 8% for smelting aluminium.

A simple (but not perfect) measure for lighting efficiency is the number of lumens (a measure of light intensity) a lighting source produces per watt.

A conventional incandescent bulb gets 13 lumens per watt to light your room, while a replacement LED bulb from Philips that can be bought at Coles or Woolworths achieves 80 lumens per watt (a compact fluorescent globe gets about 60 lumens per watt – see technical note at the end)

So, where is LED lighting going?

CREE (the industry leader who, it is speculated, may purchase the next best, Philips’ Lumileds division) has successfully demonstrated Light Emitting Diodes running at 300 Lumens per watt in the lab.  CREE currently sell a $10, 9.5W bulb (available in the US), which produces 85 Lumens per watt and can directly replace an old style 60W globe.

Other breakthroughs and innovations are contributing to achieving higher efficiency’s in LED lighting, including a breakthrough by German researchers http://www.ciol.com/ciol/news/217344/german-researchers-cut-energy-loss-half which will not only effect LED lights, but laptop and mobile phone chargers, cutting losses in today’s most efficient power supplies by half from 10% to just 5%.

Taking all this into consideration, according to the US Department of Energy SSL (Solid State Lighting) program http://energy.gov/eere/ssl/solid-state-lighting we should be able to achieve wall plug efficiencies of 250 Lumens per watt by 2020 which means that a conventional bulb replacement in 2020 would be available using only a third of the electricity of today’s LED bulbs.

3 Watts to light a room

At that staggering rate of 250 lumens per watt, it will only take 3W to light a room, when it used to be done with 60 Watts of power. This represents a 95% reduction in energy required for lighting.

This will have a profound effect on the world’s requirement for lighting energy.  We can expect  – on an absolute basis – that 19% of the world’s electricity which is currently used for lighting to dramatically drop by at least 75%.  On today’s numbers the reduction is the equivalent of the entire electricity consumption of the European Union.

In developed nations these huge efficiency gains from LEDs in the lighting sector will contribute to the continuing restructure of the electricity supply industry, which is currently facing a death spiral unless it can electrify the remaining residential energy services coming from fossil gas and supply a fast tracked electrification of the world’s vehicle fleet.

In developing countries, rooms that can be lit with 3W and task lights with even lower electricity consumption. This means that almost all the remaining 1.5Billion of the world’s population without an electricity supply will be able to access one at very minimal marginal cost in the next 5 years.

While energy requirements and costs for lighting go down, photovoltaic and battery efficiency’s are going up and their costs are coming down as well.  This nexus means that turnkey solar photovoltaic panels, with batteries and high performance lighting will be the mobile phone of the all-electric renewable revolution. leapfrogging the old fixed line poles and wires alternative creating ubiquitous world-wide electricity provision.

LED’s will be the starting point and other services such as mobile phone charging, laptops, basic machines (sewing) and cooking will flow from there.

In order to focus capital and research and development efforts  towards achieving the lowest cost and highest efficiency lighting, wealthy countries such as Australia should be specifically focussing research and development efforts.

This can be done through institutional and non-institutional research grants (equivalent to the US DoE and EU programs) and agencies such as the Clean Energy Finance Corporation. To be effective it must make inroads into financing wholesale changeovers of the nation’s lighting infrastructure ato use the most efficient technology as an incentive for suppliers to retool, upscale and mass produce the newest and highest performance LEDs.

In addition, halogen and fluorescent lighting should be phased out the same way incandescent lighting has been phased out to create even greater incentive to researchers and developers and manufacturers.

The future is looking bright for LEDs and the applications are unlimited, LED’s have had a strong impact on the auto sector, street lighting, appliance back lighting, bicycle lighting and are now even being used for greenhouses saving significant energy when growing food in controlled environments.

(Technical note: These are wall-plug efficiencies meaning the efficiency measurement is taken at the 240 Volt electrical socket, in the case of the LEDs if the measurement is taken at the correct DC voltage of the semiconductor then the lumens per watt rating is quite a bit higher. However wall-plug efficiencies are the most useful measure for consumers to compare with existing lighting and they are commonly quoted).

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  1. nakedChimp 6 years ago

    nice optimism going on here.. make it so 😉

  2. Andrew Thaler 6 years ago

    I pulled a LED ‘public streetlight’ out of a rubbish bin on Friday… a 25 watt ‘StreetLed’ unit. Little bit of water ingress around the day/night sensor and some small internal corrosion. All it took was a quick 1 minute re-wire and a new lead and presto: it works well. $300 light, installed for only 6 months and chucked in a rubbish bin by an electrical company. Seems people ‘in the industry’ don’t understand the resilience of LED lights. It does a better job than an 80W Mercury Vapour unit. I am impressed with my ‘find’.

    • Dave Blake 6 years ago


      I replaced my 40W flouro kitchen light with 3 x 1.8W aquarium lights, one on top of the fridge, one near the sink, and the other fixed on an exposed beam over the stove. Get rid of the suckers, used 2 “tool clips” to hold it in place, These ones have an in-line switch, very handy. Will not win any home beautiful awards, but give me 6W vs 40W any day.

      Kitchen light switch now taped over

      Have a look here

      Na Na Neddy

    • Miles Harding 6 years ago

      Good find!

      At 250 lm/w, those CREE lamps mentioned are something like 50% efficient at converting electricity into light and probably at the limit when reasonable colour (white-ish vs 555nm green) light is considered.
      Gone will be the inadvertent vent holes in ceilings.

      I was thinking that this will be most beneficial in the third world, where a home lighting system will get smaller, safer and less resource intensive.

      The next hurdle may be running out of the rare dopants used to make the LEDs.

  3. Alexander Dudley 6 years ago

    This will surely be enough to impact the coal profit projections and make marginal projects like Maul’s Creek untenable.

  4. JohnRD 6 years ago

    Would it make sense to convert the wall sockets to DC power at the logical voltage for LED’s? The DC power could could come direct from solar PV with a small battery to provide reliable power during blackouts? I would have thought it an easy job to connect lighting circuits to DC at the switchbox?
    For that matter are there other power uses in the house that could be converted to take advantage of the DC coming from solar PV? Some things like, charging computer batteries, involve converting AC to DC before it can be used. Other things like normal stoves, radiators, electric jugs etc. could use DC or AC.

    • Chris Fraser 6 years ago

      I wondered the same thing. Although the current would be negligible, it would require duplication of wiring for dc applications. Still, you can energise directly from battery and not suffer the conversion losses.

      • JohnRD 6 years ago

        Chris: In my switchbox there are a number of separate lighting switches. Hence connecting lighting to DC should be easy. There are also a number of separate power switches so it would be possible to convert some to DC while retaining AC where it is appropriate.

        • Matthew Wright 6 years ago

          In new houses they just put the left side of the house on one or two circuits and the right side of the house on one or two circuits with an RCD for each. Lighting and power are now on the same circuits to save on labour/wiring costs.

          • Chris Fraser 6 years ago

            Thanks Matthew. I hope the Australian Standard makes it ok to put lights and 10 amp power points on the same circuit.

          • AC Tesla 6 years ago

            I don’t know where you got this Matthew. There is no standard on how a house is wired. It’s always a matter of practicality and balancing power needs and the ease of doing it. I’ve seen all outlets on a couple of circuits and overhead lighting and cans on others. Or a mixture of lights combined with outlets. Different contractors and electricians do it differently. There are charts etc. How much voltage, how many amps, the size of the wire, the length of the run. There are so many variables.

    • Matthew Wright 6 years ago

      I don’t think it would. As mentioned in the article new breakthrough’s out of Germany are increasing the efficiency of AC – DC power supplies from 90% (for the best ones) to 95% efficient. (The really cheap ones are around 80% efficient today)

      At 95% efficiency their is considerable cost saving and flexibility of not having a separate wiring rail (which also adds safety issues) to not make going to DC wiring in houses worth it. There was an industrial consortium with a few large consumer electronic companies involved that was investigating DC powering of houses but I haven’t heard from them. We pay a price for standardisation and sometimes it is worth it.

  5. Matthew Wright 6 years ago

    Two things I missed in the article.
    1. It seems that activity based lighting is seriously being considered for the domestic market. So you would have your 10W today (3W in 2020) 60W incandescent replacement LED pendant light, lighting you room. If you leave the room for more than five minutes and leave the light on the light will reduce to 30% of it’s full output. Upon sensing heat or movement it will turn up to full brightness. The marginal cost of adding this capability once it is done in the millions by CREE and Philips will be insignificant. This is how the bulb will come when you purchase it for $5 at Coles/ Woolworths / Bunnings.

    2. Background light detection will also be included that will vary the output based on the ambient lighting conditions. So at dawn and dusk and during the day the light in the room will be measured and the output of your artificial LED lighting will be adjusted accordingly saving even more energy.

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