Tradable White Certificates (TWC) schemes, also labelled Energy-Efficiency Certificates schemes, were recently implemented in Great Britain, Italy and France. Energy suppliers have to fund a given quantity of energy efficiency measures, or to buy so-called "white certificates" from other...

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...