You can watch Lux’s interview with Shuji Nakamura here: 

The smart city revolution shows no signs of slowing down, and the opportunities for the lighting industry are ripe for the taking. In the run up to Lux’s Lighting Fixture Design Conference, which will run from the 21 to the 22nd of February in Central London, they reveal their top five smart cites, where lighting is allowing city authorities to reimagine how our population centres are managed.

5) Los Angeles

Los Angeles is currently seeing through a plan to replace every old sodium-vapour streetlight with smart LED fixtures. The city is now 80 percent of the way through the project, which has seen the conversion of nearly 200,000 street lights. The project has saved the city over nine million dollars and has acted to reduce crime.

The existing streetlight poles are being replaced with ‘smartpoles’, which are fitted with 4G LTE wireless technology and act to improve phone reception in the tightly packed city. The smart street lights are also capable of alerting city authorities when a fixture breaks down and is need of repair and some are also able to monitor and compile analytics on traffic levels and the availability of parking places.

As we reported last year some Los Angeles street lights are able to use sensors to listen out for car crashes, reporting them to the emergency services when they occur.

Singapore is aiming to become the world’s first ‘smart nation’. Sensors and cameras are being installed to track absolutely everything from traffic to the capacity of wastepaper bins.

In Singapore lighting plays a role in the city’s incredibly smart transport network, which utilises road sensors, smart traffic lights and smart parking.

Late last year Philips Lighting announced a partnership with the Sentosa Development Corporation to develop a connected streetlight management system on Singapore’s island resort of Sentosa.

It was also recently announced that visible light communication (VLC) is being installed in the massive CapitaLand Mall to create an indoor positioning system that allows shoppers to find their favourite stores amid the mall’s labyrinth of aisles and corridors.

The authorities in Singapore have also joined forces with Scottish Li-Fi firm pureLifi, in an attempt to bring the revolutionary technology to the South-Asian city-state.

Copenhagen is already one of the world’s most sustainable and smart cities and it aims to become carbon neutral by the year 2025. Nearly half of the city’s street lights were replaced recently with LED. A number of these new fixtures form the backbone of a growing smart lighting network.

The LED streetlights brighten when vehicles approach and then dim after they pass, ensuring that roads are not continuously illuminated when it is not necessary. This is a safer option than turning off streetlights altogether in order to save money, which has been the case in the UK.

The sensor-laden light fixtures are also able to capture data and analytics and are able to help coordinate the city’s services. For example, fixtures can alert city authorities that waste bins need to be emptied.

San Francisco was arguably one of the first smart cities in the world and given its location, near Silicon Valley, this should hardly be surprising.

The city has more LEED-certified buildings than any other in the United States and a connected city initiative enables residents to locate parking places.

It was recently announced that 18,500 of San Francisco’s light-pressure sodium street light fixtures would be replaced with smart LEDs.

Will tunable street light breakthrough silence LED critics? PLUS: Smart street lights tell cities when to salt frozen roads. AND: LED protest signs take centre stage at demonstrations. Lux Today 7 February 2017.

While all the sound and fury has been coming from the human-centric lobby, there’s been a quiet revolution going on in the agricultural sector. LED technology has brought massive change to the lighting for horticulture sector and the rearing of livestock. By creating LED systems that offer special spectral outputs, crop and livestock production is enhanced, reducing costs and increasing profits for farmers, while at the same time improving the quality of the product.

Historically, lighting in agriculture was seen purely from a human standpoint. It may be that our light sources left us with little option than to make the best use, or what we perceived as best use, of those sources. Now that we have a ‘tunable’ light source we are able to focus on providing the plants, birds and beasts with the best growing environment.

Horticultural lighting

Research has identified specific wavelengths that are needed to promote growth and fruiting in plants.  By applying LED technology it has been possible to create dedicated lighting systems.

For example: chlorophyll absorption occurs in two ranges, 400-500nm and 600-700nm, and that means plants grow most efficiently under blue and red light. It’s worth noting here that plants are seen to be green because they reflect that wavelength. Green light is of no use to the plant at all.

The amount of light required for photosynthesis to take place matters because there is a direct relationship between the two, up to a point. There is a light saturation point where the plant cannot absorb any more chlorophyll, at around 700 micromoles per m2 per second. Any further illumination is a waste of energy (and money).

EXPLAINER: Micromoles

Lighting for plants is measured in micro-moles per second. Micromoles measure the number of photons that pass through a target area; one micromole of light equals a little over 62 quadrillion photons. That sounds very complicated but a new range of spectrometers is now available that provides micromoles per m2 per second readings as simply as they do readings in Lux. 

Artificial lighting has been used historically to help extend the ‘growing day’ but we are seeing a move towards total managed environments where artificial lighting provides 100 percent of the illumination in the growing sheds. The LED systems are tuned to provide specific wavelengths according to the growth cycle of the specific plants.

Blue light can stimulate flowers to open up, beginning the plant’s daytime circadian cycle

Red light (and enhanced red light) is good for stem growth and flowering

Infra-red light can mimic the effect of sunset

The ratio between blue and red LEDs is specific to the plant type.

Poultry shed lighting

Getting the light right for poultry breeding is essential, because getting it wrong can be catastrophic for the population of a poultry shed. Stressed fowl become aggressive and it has been known for entire flocks of chickens and turkeys to be destroyed overnight as a consequence of the violence wreaked by the birds.

Research has identified the wavelengths that domestic fowl best respond to and it has been possible to create lighting that mimics the forest under-canopy lighting that birds ‘remember’ in their genetic make-up. This means that domestic fowl have peak sensitivity in the blue-green range, from around 500nm – 700nm, but there is also a substantial response in the UV(A) range – chickens can see ultra violet light that is invisible to humans.

Light at the red end of the spectrum needs to be handled very carefully. Red light promotes sexual activity and growth rate, though it is also thought that the excitation caused by the red wavelength can also be the cause of aggressive behaviour in well-populated sheds.

For the producer, the ideal situation is to create an environment where poultry do not exhibit stressful behaviour, such as over-eating. Layers also need to produce eggs with consistent sizes and ample shell thickness and fowl grown for their meat need sufficient environmental stimulation so that they move around, helping muscle development.

An LED system using specific wavelengths during the course of the day can result in an ideal outcome for the producer. It will produce calm birds that eat less but convert more of that food into body mass, they also come to maturity more quickly in a stress-free state, which means better meat for the customer.

Pig and beef unit lighting

Generally speaking, a lot of research still needs to be done on lighting for pigs and cattle. As we get closer to the human condition, the effect of 100 percent artificial lighting environments suggest that the situation is complicated.

Some of the data is to be expected:

24-hour illumination of pig sheds has reported detrimental effects

24-hour darkness is not an optimal condition

Piglets and weanlings benefit from additional daylight hours, but reproductive behaviour in boars is enhanced by reduced daylight hours. It all sounds very human.

From the point of view of the unit manager, one piece of information is valuable; neither pigs nor cattle appear to have any response to red light. This means that units can be supervised during the night-time by using red lighting – sufficient for security and over-seeing without upsetting the desired circadian rhythms of the beasts themselves.

As research data becomes available, it will be possible to design a lighting regime for pig units and cattle units that is cost-effective for the producer and most beneficial for the beasts themselves.

In summary, as the world’s demand for food increases, producers will need to find the most efficient ways of raising crops and livestock. For those products to have any real nutritional value for the (literal) consumer, then it is beholden on those producers to make sure that growing conditions are optimised for each species. LED lighting is well-placed to deliver the appropriate illumination.

Delivering the inaugural annual lecture of the Worshipful Company of Lightmongers, he said: ‘We need to find ways of delivering increasingly sophisticated lighting services to the whole of humankind…in ways that cause considerably less impact, which probably needs less total economic activity.

‘Lighting is responsible for anywhere between 16 and 18 per cent of total electricity consumption in the world today, depending on how you do the calculations. So this is an absolutely massive part of the challenge. And although it’s rarely spoken about in those terms, people are beginning to understand that if we are going to make a difference to this story, we have to make a difference on lighting.’

Referring to the barrage of criticism from campaigners over the UK Government’s decision to approve a third runway at Heathrow Airport in London, he pointed out that aviation is responsible for 2 and 4 per cent of total global greenhouse gas emissions.

‘It’s relatively small in fact. When you compare lighting to these other big sectors, you can begin to see why it is people are focusing suddenly on the need to get lighting right.

‘What we know is that if you back right back before electricity to when people were using whale oil and tallow and candles, the contribution of the lighting industry as a whole has remained astonishingly constant over hundreds of years. It always contributes around 1.7 per cent of total GDP in any one year.

‘This rather amazing statistic was unearthed by Professor [Jeff] Tsao in the paper he wrote in 2010. And I quote: “New applications of increasingly efficient lighting technologies have consistently offset the energy efficiency gains from new lighting technologies almost exactly, leaving the portion proportion of global GDP attributable to lighting essentially unchanged for hundreds of years”.

‘So lighting’s always had this critical part in the economy of human societies at different points, at roughly 1.7 per cent of GDP.

’The problem is, we need to do something about that,’ he told a London audience of lighting executives. ‘I hope this isn’t going to upset people here but we kind of need to get that figure down. Because if we are to have a massive contribution from lighting to addressing this problem, we need to find ways of delivering increasingly sophisticated lighting services to the whole of humankind – not just the rich world – in ways that cause considerably less impact, which probably needs less total economic activity.’

However, he praised the lighting sector for its technological achievements, especially the development of the blue LED by Professor Shuji Nakamura and his team in the 1990s. Quoting the US Department of Energy, he said: ‘ “the widespread introduction of LEDs today will reduce electricity consumption by around 348 TWh by 2027, equal to the output of 44 large power plants, saving more that $30 billion at today’s power prices”. So you can see why this is going to have an impact on GDP. It takes $30 billion of economic activity out of the US economy, that translates through into the economic multipliers.

‘If the Indian government were to replicate the LED roll-out that it is currently undertaking in Pondicherry, it would reduce electricity demand by over 50 TWh and cut consumer bills by over $3 billion. These are just massive changes that are underway now.’

He also highlighted the president of Institute of Physics’ claim that the optimum use of LED lighting could reduce lighting’s share of the global electricity consumption in buildings from 19 per cent to 4 per cent. ‘That translates to the total electricity consumption of Europe.’