Enjoying the energetic hum of solar panels

If you have ever heard the sound which solar panels make, you may know what I am talking about. Not the panels themselves, they are silent, but the faint buzz of the equipment which feeds the electricity into the grid. A sort of energetic hum.
It is a sound that hundreds of thousands of homeowners across the UK have come to experience. That something as basic and intangible as electricity can be produced from a few flat panels and a dose of sunlight, right on your own roof, is amazing, and faintly empowering. Like making your own bread. It is something we want every school in the country to be able to take advantage of, if it wants to.
Schools are perfect candidates for solar. They have big roofs and use lots of energy. They are in the hearts of communities. Quite a few schools already have solar, but many, many more do not. Across England and Wales we estimate that more than 90 per cent of schools probably do not have solar panels, held back by the many barriers which still stand in their way. Some of these barriers are procedural – roof ownership, bureaucracy – but the main one is financial. Panels make money in their lifetime, but they need to be paid for.
Friends of the Earth started its Run on Sun campaign to overcome these problems and to create the conditions in which every school in the country can go solar. The prize is large.

Big potential
If every school in the UK could install a 50kW system they could save more than £200 million a year, and produce enough electricity to power more than 300,000 homes. That is real money, and useful amounts of electricity.

Of course schools with solar will not make much difference to tackling climate change in and of themselves, but they are a start, and an important symbol. The educational value of having solar in the classroom will bring benefits far beyond the kilogrammes of carbon. To make the most of this, Friends of the Earth has helped to produce a set of materials which can be used in the classroom. In any case, after schools we can move on to other public buildings – hospitals and libraries – not to mention millions of homes, offices and factories.
If 15 per cent of the UK roofs had solar, they would generate as much electricity as six existing nuclear power stations. And we could probably deploy them in less than ten years.
But enough big numbers, what about the individual school?
School by school
There is no set size to how big a system a school can install – it all depends on the roof and how much money they have. A small primary may only manage a 4kW system made up of perhaps ten of 15 panels. A big academy on the other hand might be able to install a 250 kW one.
For the purposes of calculation, Friends of the Earth has assumed a good-sized system of around 50 kW. A system of that size might cost £60,000. That’s a lot of money, but it will make far more than that over its lifetime. Depending on how the panels are paid for and financed the school could earn up to £8,000 a year, and will certainly not lose money.

On average a set of solar panels receiving the feed-in tariff will repay their capital costs within six to nine years. If the school has no way of raising cash up front, there are a few companies which will pay the upfront costs in exchange for the majority of the panels earnings. Of course, schools are not allowed to borrow money, except from their local authority, so in essence these companies ‘rent the school’s roof’. In these cases, the benefits to the school are more likely to be in the order of a few hundred pounds a year, but of course there is no risk.
If schools were able to borrow in order to invest in solar, these schemes would be even cheaper, and more schools than ever would be able to get even greater benefits of going solar. This is why Friends of the Earth is asking for the restrictions to be lifted on schools so that they can borrow to invest in solar.

Environmental benefits
Money is important for schools, but it is not the main reason Friends of the Earth is interested in solar. Electricity generated by a schools solar panels is either used in the school itself or sent to the local grid to be used by other consumers nearby. This reduces the amount of power which must be drawn from power stations.
A 50kW array would be expected to generate around 42,500 kWh of electricity a year. Much of this electricity will be used in the school itself, but any generated at other times will be sent to the grid for others to use.
Every unit of electricity from the panels reduces carbon emissions by about 445g, so over a year a school might save around 20 tonnes of carbon. We know this is working too because rooftop solar is showing up as reduced demand on the national grid (the grid works a bit like the road network – the main transmission lines are like motorways, and local grids are like B roads. Rooftop solar usually feeds into the B roads, reducing the traffic on the motorway).

Obviously, the best power is the power you don’t use, and one of the criticisms often levelled at solar projects is that the money should be spent on energy efficiency first. The two should go hand in hand, and many schools have used the installation of solar panels as the impetus to do other important repairs or upgrade to the roof or insulation.
There is evidence too that generating your own electricity makes you more aware of the power you use, and more likely to be energy efficient. Research from the Environmental Change Institute at Oxford has estimated that households with solar panels, and crucially displays showing production and consumption, may reduce their total electricity use (grid and solar) by as much as a fifth, purely through behavioural change.

Just the start
The UK is on the verge of something really big. Renewable energy is progressing so fast that the old energy order is beginning to crack. Already renewable technology is supplying around a fifth of Britain’s electricity, and its growing. Costs too are falling. Wind and solar are already cheaper than nuclear and will soon be cheaper than gas. But Friends of the Earth wants more than just a clean energy system – we want everyone to be able to take advantage of this new system. We want communities and individuals to be able to own a stake, and bring power closer to their lives. Putting solar on schools might seem like a small thing against that, but it is a crucial step on the journey.

Further information