Big Solar Coop


The Vision

The Big Solar Coop is a new approach to community solar which will deliver 100 MW of new solar by 2025. It is an evolution of the current community solar model and driven by the same force – dedicated and talented people. Most are volunteers, some are (sometimes) paid – let’s call them solar activists.

In the current model, activists generally belong to a single solar co-operative, which is generally based in their region. They take on a bewildering range of tasks:

  • Site finding
  • Landowner negotiations
  • Business planning
  • Fundraising and outreach
  • Technology procurement
  • Build supervision
  • On-going business management
  • Co-op governance

In many small solar co-ops these roles are often taken on by a single person or very small group, sometimes for years on end. Some may like it that way, but for many it turns out to be a frustrating experience, and an unproductive one. Many solar co-ops with larger ambitions have stopped at one installation – only a handful have done more than scratch the surface of what is possible locally. Dedicated activists become stuck servicing onerous management requirements instead of developing and building new solar.

The Big Solar Coop will take a different approach. Instead of joining a small local co-op, activists will be invited to join a UK-wide solar co-op, which is run by several groups working closely together. In this new model, an activist might be part of their local site- finding group but also part of a national group specialising in one aspect of project delivery – for example marketing or solar PV research. We will nurture and grow our activist base by:

  • Breaking down the work into more manageable portions to enable people with less time to participate
  • Encouraging specialisms and the increase of expertise
  • Providing support through peer mentoring and paid staff
  • Bringing volunteers together with a sense of purpose, achievement and fun

A larger scale approach brings other benefits – increased purchasing power and standardisation of approach will enable community solar to be viable under much harsher commercial conditions. Crucially, the removal of duplicated functions frees activists up to do the important work they need to do – not everybody wants to or needs to scrutinise accounts, book halls for AGMs, or update the website.

Increased scale brings challenges too. Activists must retain the crucial sense of ownership. Communications can be harder when they cannot always be face-to-face. Local knowledge is often key to success. And although some struggling co-ops might welcome the chance to merge with a larger entity, it’s vital that the Big Solar Co-op does not step on the toes of still-vibrant local co-ops.

Our experience is that people from all walks of life want to be involved in something big, and are prepared to work hard to make an impact. In this we are inspired by the achievements of large-scale grassroots movements such as Extinction Rebellion and the Bernie Sanders campaign in the USA – and we will use some of the approaches and tools they have developed.

We’re focusing on solar embedded within communities – principally on rooftops rather than solar fields. There are many such sites for solar in every village, town and city, right next to or on top of buildings that need reasonably priced, sustainable electricity. That demand is going to soar as electric vehicles take over. Sooner or later every suitable rooftop will need to have solar panels. The key question is – who will own them and who will benefit? We think the community sector is uniquely well placed to lead this new solar revolution.

To do this we will be able to use some of the things we have already built together:

  • A network of committed local activists with the experience to deliver and the enthusiasm to recruit many others
  • A great track record in installing and running solar arrays, and in working with owners and users of the building underneath
  • A proven, stable, not-for-profit structure which is able to raise significant amounts of capital anywhere in the UK

But we also need to take the time to lay the foundations for this new model. The work we need to do, and for which we have already obtained significant grant funding, falls into two main categories:

A. Building a new structure for activists to work together

Our vision is of a network of mutually supporting activists organised into small groups around specific tasks or localities. For that to work effectively we need to put in place the glue that holds the network together:


We need to spend time explaining the vision and getting both existing and new activists on board. While we have already started this process we need to dedicate a full-time resource to energise, link and support our initial network around the Big Solar Co-op vision.


Collaborative working is at the heart of our plan. We will create opportunities for activists to meet face-to-face and work together – small regional meetings and larger convivial gatherings. We will put together a simple set of digital tools to support everyday collaboration and provide basic training in their use.


We will design a training and support program with a grassroots focus on site-finding, fundraising, solar technology, finances and marketing. This program will itself be largely delivered by well-supported volunteers and peer mentors. At the same time there is a role for paid support – where specific expertise is not available from volunteers, or where continuity and guaranteed professionalism is required. We will recruit a dedicated support officer to be based within Sharenergy so that our extensive experience of the sector can be made more available at grassroots level.


The Big Solar Co-op will own hundreds or thousands of installations, while retaining a community-led, community–owned structure. We need to spend some time establishing the best legal and governance structure for this new model, building where possible on approaches that have already been shown to work.

B. A new business model

With the withdrawal of subsidies it is currently not possible to build viable rooftop solar in the UK except in a very small subset of special cases. As solar costs fall the situation is changing slowly, but existing community solar models will still not be competitive for years. We need to speed things up – which means a new approach:


Most of the cost of a solar installation is now not in the panels and hardware but in labour, management and regulatory costs. We need to engage with solar equipment providers and installers to reduce costs and change the way we work so solar installations are easier to put up and take down, maintain and operate. With relatively small improvements in technology and cost we can open up previously unviable sites.


We need to work to get more out of our panels once they are installed. That means designing better systems for monitoring, inspection, cleaning and optimisation than most community solar groups currently employ.

Site finding

We need to develop a more sophisticated and systematic approach to finding and signing up the owners and users of the roof-space we need. We need to create more flexible legal agreements and better resources to help explain our offer. The members of our network need training to approach local rooftop owners or to build strategic links to organisations with hundreds of suitable sites.

New opportunities

For decades the main industry drive has been towards cheaper panels and installations. Now that the costs of panels are small proportion of the total, we are seeing a move towards high efficiency modules and more sophisticated technology – bifacial modules, tracker systems, power maximisation. At the same time a whole new set of potential electricity users are coming to market in the form of electric vehicles and heat pumps. We need to work to form strategic partnerships in these areas.

Outreach and funding

The Big Solar Co-op will need to develop a strong set of tools to engage and retain the interest of the wider public in order to grow its activist base, reach more community stakeholders and attract funding. We need to design a new approach to community shares where periodic, site-by-site offers are replaced by a more constant rolling offer with more flexible terms, consistent returns and a sizeable development fund.

Sharenergy has been deeply engaged in UK community solar from the beginning. The Big Solar Co-op is the culmination of 8 years of experience with the technology and the realities of running solar co-ops day to day. We have been listening closely to what community solar activists are telling us. Our sector has to date been overwhelmingly reactive – completely dependent on Government subsidy and therefore obliged to constantly adapt approaches based on the vagaries of policy. The removal of subsidy changes the picture – it requires us to take a closer look at our own model and what we can improve. The Big Solar Co-op approach provides solutions to issues that we have previously identified but have not had the resource to address, based on daily feedback from the groups we work with.