Light Emitting Diodes (LEDs) are more efficient than incandescent lights - fact. But just how much does this efficiency really impact on global greenhouse gas emissions? It seems that it becomes really significant when their adoption spreads worldwide. By Jeremy Torr.

SINGAPORE, 4 March 2017. It has been estimated that in 2016, some three billion LED lamp units were sold and fitted. This can only have increased in 2017, with up to 30% more being sold last year. By 2020, it is estimated that China alone will be able to churn out some 1.2 billion units a year – and that’s not counting the US, Europe, Taiwan and Russia.

Researchers have calculated that overall, and for the same level of illumination, LED lighting reduces power consumption by an average of 40-50% when compared to fluorescent lights, and 80% when compared to incandescent bulbs. For number nerds, the output is some 2-300 lumens/watt for the most efficient, compared to only around 10 lumens/watt for a standard light bulb.

So the good news is that the global move for consumers and businesses to opt for LEDs is saving almost half a billion tonnes of CO2 that would otherwise have been emitted as part of the process of generating power for old, inefficient lights.

Easy to Adopt

“The efficiency of LEDs is essentially what makes them [attractive],” said LED market analyst Jamie Fox, from research outfit IHS. Fox noted that the attraction of LEDs was that it was simple plug and save, unlike other conservation efforts that require people to reduce consumption or make lifestyle changes.

“LED component and lighting companies were responsible for reducing the global carbon (CO2e) footprint by an estimated 1.5 percent in 2017, and that number is likely to continue to grow as more LEDs are installed around the world,” said Fox.

Although the amount of power used in the manufacture of LEDs was not considered, the efficiencies of scale will likely reduce that compared to the established technology used in making glass-and-metal based lights.

But it’s not just homeowners who are making a difference. There are currently well over 300 million streetlights across the world’s cities and towns, with the number expected to grow to 363 million by 2027. So that in around ten years, the old market for traditional sodium and halide lamps will have shrunk to about 10%, with smart LED lights – ones that report back on local conditions and use energy most effectively – almost one third of that.

And you must be blind to not have noticed that almost all cars and trucks now come with LEDs instead of bulbs. Although the jury is still open about the health and visibility aspects of high power automotive LEDS, with blue-light component in white LEDs suspected of causing toxic stress to the retina, there is no doubt they use less juice.

In tests comparing normal and headlamps in one brand of German car, LEDs showed CO2 reductions of over 1 gram per kilometre. The conventional lights drew 135watts, whereas the LEDs only used 80watts for the same output. That might not sound much, but multiply it by a potential 1 billion cars on the road and it certainly makes a difference.

Down on the Farm

And in offices, where lights are usually left on way longer than in the home, new fluorescent-replacing tube LEDs are making significant inroads. Some forecasts predict around 1 billion tube LEDs will be fitted in commercial premises by the end of 2018. With a saving of up to 50% over normal tubes, and a much longer life too, the move makes good sense.

Even more surprisingly, LEDs are sneaking into the agricultural sector too, with special wavelength LEDs being used to help nurture plants most effectively in market gardens and cannabis growing operations.

LEDs offer other benefits, too. For example, LEDs have a longer life span than traditional bulbs and fewer are produced, so the emissions and pollution associated with the production, shipping, sale and disposal of the products is also lowered, says IHS’s Fox. “LED component companies and lighting companies have transformed the industry,” he said.

Secondly, unlike fluorescents, LEDs do not contain mercury, although some warnings have been sounded about cheap units produced with an excess of lead and arsenic. Nonetheless, the amounts inside the lights are much less, and disposal easier.

So the overall effect of those millions and millions of LEDs being installed everywhere from Bhutanese mountain villages to Jamaican high streets is that the equivalent of 162 coal-fired power plants could have been shut down – with little or no effect on the light in our lives.

“Unlike in other industry sectors, workers at LED companies can honestly say that by selling more of their products, they are helping to reduce global warming,” says Fox.

Maybe it’s time for you to help too – are you an all-LED household yet?