The number of ground-mounted solar parks is increasing across the world in response to energy decarbonisation. Solar parks offer an opportunity to deliver ecosystem co-benefits but there is also a risk that their development and operation may be detrimental to ecosystems. Consequently, we created the Solar Park Impacts on Ecosystem Services (SPIES) decision-support tool (DST) to provide evidence-based insight of the impacts of different solar park management practices on ecosystem services. The SPIES DST is underpinned by 704 pieces of evidence from 457 peer-reviewed academic journal articles that assessed the impacts of land management on ecosystem services, collated through a systematic review. Application to two operational solar parks evidences the commercial relevance of the SPIES DST and its potential to enable those responsible for designing and managing solar parks to maximise the ecosystem co-benefits and minimise detrimental effects. Further, evaluation using data from nine solar parks across the south of England demonstrates the validity of the DST outcomes. With the increasing land take for renewable energy infrastructure, DSTs, such as SPIES, that promote the co-delivery of other ecosystem benefits can help to ensure that the energy transition does not swap climate change for local scale ecosystem degradation, and potentially prompt improvements in ecosystem health.