Interesting business models are emerging to help spread the use of small to medium scale and community renewable energy. Two of them are social enterprise companies who are raising investment by crowdsourcing, and investment by institutional investors through a third party acquired or set up specifically for this job.

The intermediary companies lease roof space for solar PV installations, take the risk and manage the installations and maintenance, while the benefit for the recipient buildings' owners is no upfront cost and reduced energy costs.

With the removal of counterparty risk and a highly competitive Power Purchase Agreement (PPA) there are opportunities across all sectors to benefit from free rooftop solar installations.

Right: A solar panel installation at Rodborough School, Wey Valley, England. The School can now generate up to 27.2kW from the new solar panels that have been installed on two of its roofs. The finance was raised by the Co-operative like the one described below.

As an example, a scheme is being offered to schools throughout the UK by an institutional investor, Secured Energy Bonds plc (a wholly-owned subsidiary of Sydney-based clean energy company CBD Energy Limited), who recognise that their proposition is attractive to schools because school budgets are tight and a shorter term view needs to be taken on investments.

SEB works in partnership with an installer, in this case Solar Cells Ltd, an established UK company who have been seconded as UK acquisition and development advisors for SEB.

There are currently working on raising finance for a nationwide programme of rooftop solar projects in 22 English schools. 

By way of example, a mid-sized rooftop of around 1600m² of usable space – consuming a national average production level (950kWp/kWh) - could save well in excess of £400,000 over the course of the lease. The flexibility of its structure can be beneficial to landlords and tenants alike, and with a 10 year option due for imminent release, the options across all manner of sectors are numerous.

Chris Hall, Business Development Executive and spokesperson for Solar Cells Ltd said: "The UK has developed just 2.5GW of solar capacity to date, against a government target of 20GW by 2020, and with bank loans and other more traditional forms of finance still proving hard to come by, and prospective clients struggling with a host of spending priorities, the installation of a solar array will seem prohibitively high, indeed to many a luxury."

Initiatives like this are available to all manner of organisations able to offer a suitable rooftop site, in both the public sector and business – in agriculture, industry and many other fields. It means all sorts of organisations can enjoy the full range of benefits which come with solar power, reducing their energy bills whilst playing their part in the switch to cleaner energy sources.

"The financial model that we have constructed, to develop solar projects on large non-domestic sites, is we believe a great addition in this growing market, as capital outlay, return over the investment period, and counterparty risk have each presented significant hurdles in developing sites in recent years. The Secured Energy Bonds initiative makes solar development truly accessible."

At the other end of the scale community ventures initiated by not-for-profit social enterprises. One example is the South Wales Valleys Solar Photovoltaic Cooperative, currently raising finance through a share issue to install solar panels on seven community buildings in south Wales, such as Ystradowen Community Centre (right), before summer 2014. Investors not only will receive a very reasonable return on their investment, but a feelgood factor for knowing they are helping out community buildings.

At the last count, there were at least 15 other similar ventures across the UK using a similar business model to mobilise their communities to take advantage of renewable energy and feed-in tariffs, the extra financial incentive offered by governments support renewable energy that makes these business models possible and has helped to bring down substantially the cost of manufacturing and installing systems over the last few years.