Sizing hybrid power plants under round-the-clock tender compliance in India

India aims to quadruple its renewable electricity capacity by 2030, using auction-based renewable power tenders as a mechanism to achieve that goal. We formulate an optimization problem to optimise a power producer's plant sizing for this tariff-based bidding process. The outcome is an investment optimisation model for a hybrid power system that complies with the specific Round-the-Clock tender criteria. Results indicate that the invitation to tender incentivises investment in renewable power instead of conventional thermal coal power, increasing the renewable power capacity share by a factor of 1.5 when flexibility is added to the firm capacity conditions. Further, the optimal investment outcome shows a critical dependence on the specific tender parameters.