There is something different on the street. Here in Edinburgh we have just finished a very successful trial of white street lighting to replace old-fashioned orange/yellow sodium lights. You might be surprised by the benefits it can bring.
As councils across Scotland look to cut costs in difficult financial times, improvements in white lighting technology increasingly make it a strong candidate for investing to save. A variety of technologies were trialled in Edinburgh and energy consumption was found to reduce by up to 38 per cent, with a direct impact on energy costs, at a time when energy prices look likely to continue to rise.
It also significantly reduces carbon emissions. From April, energy costs for streetlighting will be included in the Carbon Reduction Commitment (CRC) calculation. White lighting technology also lasts longer – up to twenty years compared to only a few years for traditional fittings, and it can be recycled. In Edinburgh, we are increasingly mounting street lights on modern aluminium columns which require little ongoing maintenance and have a design life of more than 50 years, compared to 30 years for traditional steel and concrete columns. They too can get recycled.
One reason why white light is more efficient is that the light is better directed at the specific roads and footways that need to be lit. This means there is less light pollution, which can affect neighbouring properties and the sky, providing a better environment for nocturnal wildlife such as birds, bats and bugs. It’s also more versatile allowing for variable lighting or part-night lighting depending on local needs. Reduced light pollution makes stargazing easier, very important in a city with a long and distinguished history of astronomy. The first observatory was built on Calton Hill in 1834, and this site, part-designed by William Henry Playfair, is being converted to a visitor attraction and galleries. Many councils have recognised the value of dark-sky friendly lighting to astronomy tourism such as the UK’s first Dark Sky Park in Galloway Forest.
The effect on humans is also interesting. Reduced light pollution can create a more agreeable, natural environment and is even thought to be beneficial to health. Although the response from the public to our trial was very positive, some remain to be convinced. White light is thought to provide a “sharper” illumination but the effect can take a little while to get used to. It has been likened to changing the lights at home from old fashioned incandescent bulbs (which radiate heat, making them inefficient) to fluorescent or LED lighting.
Just about the only potential down side of white light technology is that initial installation costs can be expensive. However, taking everything into account, the payback period for investment is normally less than eight years, providing years of “profitable” use, and, given the importance of cutting carbon, government funds are often available to help. In Edinburgh we recently received an interest-free loan of £2 million from a Department of Energy and Climate Change agency called SALIX to extend our coverage of white light technology as we look to find funds for the whole city.
It’s already clear conversion of street lighting to white light will become an important element of the overall sustainability revolution. In Scotland we are building a strong reputation for cutting carbon emissions by generating renewable energy, but invariably (and this is often forgotten) the cheapest and easiest way to cut carbon is to reduce energy waste. Improved insulation and sustainable transport forms such as walking, cycling and public transport should be high on the agenda of your local council. But white light street lighting should be added to that list too.
Jim Orr is the lead councillor for sustainability at Edinburgh City Council