Disruptive low carbon innovations have significant potential to facilitate a transition to a sustainable energy future. The UK's commitment to reduce greenhouse gas emissions by at least 80% by 2050 requires action in all sectors of the economy and wider changes to society. The energy industry is one of the largest contributors and its reconfiguration could facilitate significant emissions reductions across industry and society (Committee on Climate Change, 2015). It could further contribute to regional-specific targets such as Bristol's Zero Carbon plan. Decentralised energy has been presented as one of many pathways to ensuring humanity stays within social and planetary boundaries (Rockström et al., 2009; Chmutina and Goodier, 2014)) and is a fundamental foundation of the 'Thousand Flowers' (TF) pathway for sustainable energy (Foxon et al., 2010). Decentralised energy is seen as a more democratic form of energy provision (Sovacool and Blyth, 2015) and is posited as a potential facilitator in resolving the 'energy trilemma' of energy security, energy equity, and environmental sustainability (Goldthau, 2012). Significant lock-in to the incumbent energy regime has made such a transition difficult (Fouquet, 2016).

Emphasis is placed on a 'civic' energy sector in the TF pathway, which comprises municipal (local authorities (LAs)) and civil society actors (community energy groups, co-operatives, intermediary organisations, charities) (Johnson and Hall, 2014). Many of these initiatives are niches in the multi-level perspective on sustainability transitions (De Vries et al., 2016), with the potential to disrupt the established regime, but few have done so successfully (Hatzl et al., 2015). Community energy is an important policy area for the UK (DECC, 2014) and has been the focus for several previous studies (e.g. Hargreaves et al., 2013; Seyfang et al., 2013). The role of other important non-commercial actors, particularly LAs, has been overlooked (Hall et al., 2015) but for a few academics (e.g. Mattes et al., 2015; Fudge et al., 2016; Neij et al., 2017).

Socio-technical transitions literature has called for a more spatial approach to understandings of niche development and innovation diffusion (Bridge et al., 2013; Murphy, 2015) as energy governance is carried out at multiple scales and geographies (Smith, 2007). Recent attempts have been made to understand diffusion of solar photovoltaics (PV) as a spatial and spatio-temporal process at national and regional levels in the UK and Germany (e.g. Balta-Ozkan et al., 2015a; Schaffer and Brun, 2015). A gap exists in the literature to enhance the understanding of spatial dependency of PV diffusion at a fine-grained level (Balta-Ozkan et al., 2015a). Despite the vast majority of installations being of domestic nature, little attention has been paid to the influence of the civic energy sector in the diffusion of this technology.

PV is an important example of technology that can enable energy consumers to become energy 'prosumers' and participate in decentralised energy. The UK has almost 900,000 installations with a total generation capacity of over 11GW (BEIS, 2016). However, when compared to more distributed energy systems such as in Germany (Beerman and Tews, 2016), where citizen-owned capacity accounts for 47% of renewable energy, the UK lags behind with 0.3% of renewable capacity under community ownership (Julian, 2014). Julian (2014) suggests, despite historical factors shaping these contrasting configurations, a local energy market approach could provide a promising alternative.