We compare a range of energy efficiency policies in a durable good market subject to both energy-use externalities and price-quality discrimination by a monopolist. We find that the social optimum can be achieved with differentiated subsidies. With ad valorem subsidies, the subsidization of the...

Implicit discount rates (IDRs) are employed in energy models to capture household investment decisions, yet the factors behind the IDR and their respective implications for policy-making usually remain blurred and fractional. The proposed comprehensive framework distinguishes three broad...