This article examines the principle of full reparation in renewable-energy investment disputes. It argues that tribunals should calibrate interest towards the true opportunity cost borne by different categories of renewable investors, rather than relying on risk-free or sovereign-bond rates that understate the consequences of delayed compensation. Because renewable projects are typically equity-intensive and often financed by non-resilient investors (independent developers, cooperatives, local communities),1 uniform interest awards risk undercompensating those who assume greater risks to make a crucial contribution to the green energy transition. The article reviews arbitral decisions from risk-free and ‘forced-loan’ approaches toward methods based on the claimant’s cost-of-funds – particularly cost of debt and cost of equity – and contends that, for non-resilient equity investors, a cost-of-equity benchmark best implements the Chorzów Factory standard. Adapting the principle of full compensation to the financing realities of renewable investors not only ensures economic justice but also advances the objectives of international climate treaties.
European Investment Law and Arbitration Review