Environmental regulation of a power investment in an international market

We examine the optimal environmental regulation of three Norwegian power projects: energy conservation, a natural gas fired CCGT and a new hydro project. All projects reduce emissions elsewhere in the Nordic region, and the environmental costs of these emissions are not, in general, fully reflected in market prices. We develop a theory of second best optimal regulation for this case. The optimal regulation is found to deviate substantially from a purely domestic regulation. For instance, we find it optimal to grant a substantial credit to energy conservation. The credit is sensitive to the value of reduced CO2 emissions and whether the current Norwegian end user tax should be interpreted as an environmental or a fiscal tax.