Renewable energy investment risk: An investigation of changes over time and the underlying drivers

Building an energy system compatible with the Paris Agreement requires large-scale investment in renewable energy technologies (RET). Designing effective energy policies, therefore, requires an understanding of the dynamics of RET investment risk. This study draws on RET project data and 40 interviews with investors in Germany, Italy and the United Kingdom. We identify the five most relevant RET investment risk types (curtailment, policy, price, resource and technology), show their relative importance over time and use a network analysis of interview transcripts to identify the drivers behind the observed changes. We show that risk premiums and investment risk have declined for solar photovoltaics and onshore wind technologies in all three countries. Increasing technology reliability at a lower cost, data availability, better assessment tools and credible and stable policies were crucial elements of this declining investment risk. While policy and technology risks have become relatively less important over time, curtailment and price risks are becoming relatively more important. From these insights, we derive recommendations for policymakers aiming to accelerate the transition towards a Paris-compatible energy system.