This paper has been developed as part of the support provided to the Regional Economic Development Agency of Stara Zagora through the EU Coal Regions in Transition Initiatives technical assistance facility START. It is one of three reports exploring opportunities for economic development and diversification of Stara Zagora Region, within the context of the eventual phasing-out of fossil fuel-based energy generation, including cessation of lignite mining activities, and the decarbonisation of the economy. The accompanying two papers cover the development of sustainable agriculture and mechatronics.