Return of the DEEP: One platform to benchmark them all

The De-risking Energy Efficiency Platform (DEEP), developed within the Energy Efficiency Financial Institutions Group (EEFIG) in 2016–2023 and since 2024 hosted by the European Energy Efficiency Financing Coalition (both funded by the European Commission), is the largest open-source European database for energy efficiency investments. With more than 36,000 projects from industry and buildings DEEP aims at strengthening the ability of policymakers and financial institutions to assess risks and profitability, supporting the development of coherent and financeable energy efficiency measures. The platform provides aggregated information on investment costs, energy savings and financial performance indicators such as payback time and avoidance cost, enabling benchmarking of energy efficiency projects across countries and technologies.
This paper updates the analysis of DEEP originally presented by Rohde et al. (2018) using the substantially expanded dataset. The updated results confirm the main structural patterns of earlier analyses, including short payback periods for many cross-cutting technologies and higher capital intensity for building fabric and system-level measures.
In addition, the paper conducts a structured cross-country comparison between German and US projects included in DEEP. The results reveal systematic differences in reported economic indicators, with US projects showing lower investment levels and shorter payback periods. The analysis shows that these differences primarily reflect structural characteristics of the underlying datasets rather than technological performance differences. The findings highlight the importance of considering dataset provenance, project scale and programme design when interpreting benchmarking indicators for energy efficiency investments.