As part of the Kyoto Protocol, many countries have committed themselves tosubstantially reduce the emission of greenhouse gases within a politically imposed timeconstraint. Investment subsidies can be an important instrument to stimulate the adoption ofenergy-saving technologies to achieve...

We study the introduction of new technologies when their costs are subject to idiosyncratic uncertainty and can only be fully learned through individual experience. We set up a dynamic model of clean experience goods that replace old polluting consumption options and show how optimal regulation...