The government’s new plan for solar wants the south facing roofs of public buildings covered with PV panels as quickly as possible. The 22,000 schools in England and Wales are a particular target. Two communities are currently raising money for schools in their area. Staffordshire Sunny Schools is raising about £1m to put an average of 40 kW of panels on 25 primary schools. Plymouth Energy Community is looking for £0.5m to match a loan from the local council that will see PV installed on about the same number of schools. The two schemes are both proposing investor returns of about 5-6%, as well as discounted electricity for the schools and large amounts of cash devoted to local energy efficiency schemes. Both these companies will happily accept investors from outside their area.

Staffordshire and Plymouth will benefit from EIS eligibility, meaning that taxpaying investors will get 30% back in reduced income tax bills. EIS also avoids inheritance tax, which may be a worthwhile additional benefit for investments that will deliver value for the 20 year period of feed-in tariffs.

Other schemes, such as Oxford North Community Renewables, have also recently succeeded in raising money for school solar through funding of a ‘Community Benefit’ company funded by small investors, mostly from the local area. Crowdfunder Abundance Generation's solar schools offer will open within a few weeks. Meanwhile the emissions-reduction action group 10:10 continues with its pathbreaking 'Solar Schools' scheme, which encourages charitable giving to fund PV. Indeed the government's new enthusiasm for PV on school roofs seems to owe much to the hugely successful efforts of 10:10 over the last two years.

I’m not competent to recommend these or any other community energy schemes. However the economics for Staffordshire and Plymouth look perfectly solid: £1,000 of PV panels will generate feed-in tariff income of about £120 a year, meaning that investors will get about half of the subsidy revenue. There's plenty of cash available to fund the costs of running the business as well as channelling money into local fuel poverty projects.

The Staffordshire scheme sent me some comments from the headteacher of one of the schools in the area that has already had panels installed. Anybody looking to make investments with social value as well as a reasonable financial return might be interested in these remarks.

Paul Moon, Millfield County Primary School Head Teacher

How I teach

Fitted about six months ago, our school’s solar panels are already having a wide-ranging educational impact on several aspects of the curriculum, including science, maths and geography. Solar is a practical and local way into a complex range of inputs with an output at the end of its cycle.

There were learning messages from the start including: is this offer best value? In assemblies, we explained in age-appropriate ways how solar energy works and its benefits. For example, as an Silver Eco School, generating our own electricity could help us get to Gold.

I first heard about the Sunny Staffordshire Schools project from Staffordshire County Council’s sustainability team: funded by in part by community shares, Generation Community was offering solar panels for 25 schools, gratis. We were selected as a pilot, and the solar panels were installed over half-term in October 2013.

We wanted the children to see the practical benefits, and our site supervisor suggested using the ITC suite as the focus. With 32 computers and air conditioning, it is the single most intense user of energy.

We use known ways of scientific change, such as the water cycle, to show how solar works. Every time a child switches on a computer, they get a physical indication of how they are powering their own ITC suite with electricity generated from the sun.

We deliberately sited the visual display panel in the main corridor at a user-friendly height for the children. They are surprised to see the panel working even on a dull day. This leads to an exploration around the science of heat, light, greenhouse gases and atmosphere. Although the depth of understanding varies with age, the children understand we are reducing greenhouse gases whilst also saving money.

The solar panels also lead us to explore maths and economics. We generate more than we need for our ITC suite, and sell the surplus into the national grid. The solar panels feature in our school’s enterprise project - we are now energy producers, traders and sellers. We can calculate how much electricity is generated, used, and how much is left to trade.

Since the panels were fitted, our electricity usage has gone down, but the price per kwh has gone up in some cases. This leads to: what makes a fair measurement? We have generated almost 3,000 units from sunlight, and can start plotting graphs over a set period. We are constantly refining the way the panels can be used educationally.

Already the solar panels meet several national curriculum objectives. In history, we can investigate Staffordshire’s former coal mines and explore our growing use of nuclear power and imported gas. In geography, we can look at where electricity is stored, how it travels, and where the surplus goes. This gets us into surges in demand for electricity peaks and flows, and different seasonal and activity uses.

Children are very interested in green issues; for instance younger ones are aware of the benefits of recycling. Key Stage 2 children are increasingly knowledgeable about the need to carefully manage the world’s finite resource, realising how important it is to look after what we have and to invest in new technologies for the future.