The third ACCREU technical brief summarizes the 15 adaptation
case studies from the project, on the economic costs and benefits for different adaptation decision types in Europe.
What emerges is that in most cases, the benefits of adaptation outweigh the costs — providing a strong economic case for scaling up investment.
The analysis, carried out as part of the ACCREU project, found that all types of adaptation can be economically appraised, though more transformational measures require more sophisticated methods beyond standard cost-benefit analysis, including approaches that account for uncertainty and non-market benefits such as health, biodiversity and social cohesion. When these co-benefits are properly included, the economic case for adaptation strengthens considerably.
The research also found that results and priorities shift depending on the analytical framework used. Options ranked highly on economic efficiency grounds may differ from those prioritised under equity or climate justice frameworks, which give greater weight to the most vulnerable communities.
On the barriers side, the study identified institutional and financial obstacles as the main bottlenecks to implementation, with more transformational adaptation facing the greatest challenges due to short planning horizons, governance gaps and existing financing structures. Governance and financial enablers were found to be the most critical factors in overcoming these barriers, though social and cultural factors also played an important role.
A supporting literature review confirmed that adaptation generates positive economic returns across a wide range of contexts, but noted that societal returns consistently exceed private financial returns — meaning that even where the overall case for adaptation is strong, private investors alone will not drive the necessary scale of action. Public policy and finance will remain essential.
Technical Brief: Adaptation Economic Case Studies in Europe from the ACCREU project
Full report: Adaptation Case Study Analysis