Westmill solar

Westmill Solar

Westmill Solar is a community owned renewable energy project based in the south of England – the first of its kind in the UK. A local farmer – Adam Twine - and partners developed the project to build on the success of their earlier wind farm project. The solar farm is paid for the energy it creates and is owned as a co-operative following a community share issue. As well as aiming to produce local, reliable, clean energy, the project also seeks to get local people involved in energy production as well as demonstrating what is possible in order to inspire others.

The problem

Climate change is increasingly recognised as a real and man-made threat. Energy production which relies on oil and gas is not only exacerbating this problem but is also only sustainable for a finite period of time. There is an increasing need to consider – and expand – renewable energy sources.

The UK is also concerned about energy security and communities are increasingly thinking about their ‘resilience’. When civil unrest in the Ukraine can impact on the stability of energy supplies in the UK, people are starting to worry about how they can take greater control and ownership of their energy supply.

Community owned renewable energy projects exist throughout the UK but often on a relatively small scale. In Denmark and Germany a much greater proportion of renewable energy is owned by communities.   

Westmill Solar explain how “We believe that one of society’s greatest challenges is securing low carbon energy at a realistic price and that opportunities for us as individuals to generate renewable energy and help limit climate change are few and far between.

The Westmill Solar share prospectus explains the volatility of electricity and gas process in the UK.

The solution

Westmill Solar Co-operative is “The largest community owned solar farm in the world.” The solar farm is near Watchfield, on an old airfield between Swindon and Oxford.  It is next to the Westmill Wind Farm Co-operative, a smaller project which helped pave the way for the solar park. The wind farm started as five turbines while the farm includes arable land, a dairy herd, a smaller number of beef cattle and some other small enterprises. It was a £6 million project which could power around 2,500 homes over 25 years. 

The idea for a large solar farm was discussed with the local community who encouraged the team leading the development of the co-operative to be ambitious. In March 2011 planning approval for the farm was granted and work began in May of the same year. The site was connected to the electricity grid by July. The development was undertaken by Low Carbon Solar and Blue Energy but an option was included in the deal for a co-operative to take ownership of the project, which happened in October 2012.

Business model

The project is a five MegaWatt installation, producing enough electricity to power 1,400 homes. The solar park is made up of 20,260 polycrystalline PV panels and covers 30 acres. The PV modules convert daylight into electricity. The project shares its connection to the electricity grid via the distribution network operator, Scottish and Southern Energy, with Westmill Wind Farm.


Income is generated through the government’s Feed in Tariff (FiT) scheme. The FiT is index-linked and guaranteed for over 20 years. This provides sufficient certainty of income with an estimated average return around 10% to member shareholders. Under the Energy Act 2008, the UK Government created this new incentive to encourage the development of renewable energy in the UK. The FiT is focused on smaller scale (less than 5MW) low carbon electricity generation. It is paid per unit of electricity generated. 

Once the project was in operation, UK residents were given the opportunity to buy shares, from £250 to £20,000. As shares were oversubscribed, priority was given to people living closer to the site. Over half of the shareholders live close to the site and around 80% within 40 kilometres or with some relationship with another community energy cooperative. Enough shares were bought for the co-operative to purchase the shares from the initial development partnership. A £12 million loan was raised form the Lancashire County Council Pension Fund. Investors also receive their original capital back. 

Shares in the co-operative are non-transferable like shares in a ‘normal’ listed company. But with approval, they can be redeemed or transferred. Co-operatives run along principles of democratic membership. Westmill Solar is a ‘bona fide co-operative’ (and therefore could be understood as a social enterprise or not, depending on various interpretations.) owned by and managed for the benefit of its members. These organisations are registered with, and regulated by the Financial Conduct Authority in the UK. All members of Westmill Solar have one vote regardless of how many shares they hold, the Board is elected by the Members and only members are eligible to serve on the Board. 


This was the first project of its kind in the UK. While community owned renewable energy has existed for some time, this was the first large scale community owned solar farm project in the UK. It is currently the largest community owned solar farm in the world. In July the share offer generated nearly £6 million through share sales bought by over 1,600 members. The share offer was significantly oversubscribed. This is also understood to be the first major funding of its kind by a local authority in community-owned energy infrastructure.

The nature of the institutional investors was also innovative. There have been increasing suggestions over the past few years that local authorities in the UK should look more for opportunities to invest both closer to home and in environmental projects rather than invest in global financial markets, particularly following the Icelandic banking crisis, where local authorities lost significant sums of money. The £12 million loan from the Lancashire County Council Pension Fund was a significant precedent in this regard. 


The project aims to “combat climate change by financing a reliable source of renewable energy, provide local people and other investors with a stable, reliable source of income, and help the area transition to a low carbon future economy.” The solar farm aims to reduce carbon dioxide emissions by 2,000 tonnes a year. One further aim of the project is to demonstrate that community energy can be created on a large scale for the benefit of many. The project will also help fund a partner project which will work to help develop more sustainable energy in local communities. 

The project also aims to boost the local economy, keeping profits in the local area and attracting visitors. A team of volunteers enable visitors to visit the site throughout the year. Community energy projects also tend to have an educational and behavioural impact - members begin to care more about where their energy comes from. 

Problems and challenges

Finance was at the heart of the challenge for Westmill Solar. The total project cost was £15 million. To finance this, the project sought £10-12.5 million of loan finance with the remainder secured through a community share issue. 

Risks included timing and changes to the Government’s rules around the FiT. The project was completed just a few weeks before the FiT price was revised downwards by the UK Government.  

Other risks include high inflation, which would increase the return owed to shareholders although this is mitigated as the FiT is index-linked.  Another risk is low levels of sunshine but levels of solar radiation are quite consistent in the UK.  Other risk include potential damage through vandalism. To mitigate these, Westmill Solar Co-operative has a maintenance contract in place and relevant insurances. 


The solar farm is producing more energy than expected and members of the co-operative are working with government, policymakers and others to help encourage the spread of similar models across the UK. Founder Adam Twine says that the project “reflects a collective desire to see change. My aspiration is that it will replicated by other groups in the UK.” Westmill Solar’s Chair, Philip Wolfe, organised a conference in December 2013 to explore how co-ordination and support for community renewable energy projects could be improved and to help instigate a new body to represent the community energy sector. 

The team behind the project believe that the next stage is for community energy to be not only locally generated and owned but also locally supplied. Westmill wind and solar coop members, Adam Twine, Maurice Dixon and Pete Bishop are developing plans to develop the UK’s first community owned hybrid clean energy generator and direct supplier. This means creating demand management and power storage systems which can manage intermittency of power generation and demand. They hope this will “further strengthen the opportunity for the greater penetration of renewable energy into the UK electricity mix.”


Westmill Solar believe that there are a range of benefits to the communities in which renewable energy projects are located. In particular they “enable local people to become involved in their energy supply rather than it being imposed on them from outside by faceless corporations. This can lead to a much more enthusiastic response to planning applications, for example. 

However, the team also found that community energy projects can be harder to deliver than those by commercial developers due to the “reliance on individual, usually unpaid, volunteers; and the lack of financial resources available to the cooperative at the inception of the project. They argue that grid connection and planning are the two main barriers to community energy projects of this kind. First, as “there is no national approach to prioritising renewables in gaining connection to the grid” and second, as the “The UK planning system is very patchy and can also apply delays and uncertainty to local energy projects… Certain elements of the press have been stoking opposition to local energy projects.”

The team behind the project have also been involved in feeding into recent policy developments and proposals from think-tanks, such as ResPublica’s 2013 paper The Community Renewables Economy, which makes the case for community owned energy and explores the national and local policy barriers faced by communities. Another important battleground for this agenda is around tax incentives for investment, where advocates of community energy have been feeding in to recent policy changes emerging from the Treasury, (around the new Social Investment Tax Relief and revisions to the Enterprise Investment Scheme) seeking to ensure that they continue to provide appropriate incentives to encourage investment in community-owned renewable energy projects.

Founders’ perspective

Westmill wind farm cooperative was started by local farmer Adam Twine, originally designed to mitigate the risks of rising energy costs. However, Adam was keen to engage more closely with the local community. In 2011, Adam Twine of Westmill Farm and Mark Shorrock of Low Carbon Solar aimed to build on the success of Westmill wind farm by launching another co-operative – this time exploiting solar power technology. 

Adam was a tenant farmer, born near Oxford. Adam says that “My anxiety is that we have lived through the last 50 years as rather golden years for northern and western countries. In the future, things will change, and the people who suffer most will be the poor and the ones who haven’t got much of a voice. That’s part of what drives us – social and environmental justice.” He says much of what drives him is thinking about his children and being able to explain his actions to them in future. He says that at start of the project he “didn’t know any more about it than a layperson. I guess you have to have the passion – and I am very lucky that I have a key resource, land, at my disposal.” Adam also says that “As an organic farmer it makes perfect sense to me to use renewable energy as much as possible to make the most of natural resources and minimise my environmental impact”.


Author: Dan Gregory, Head of Policy at Social Enterprise UK (SEUK)

Source: China-UK Social Enterprise and Social Investment publication