The production of electricity on the basis of renewable energy technologies is a classic example of an impure public good. It is often discriminatively financed by industrial and household consumers, such as in Germany, where the energy-intensive sector benefits from a far-reaching exemption...

This paper shows that reciprocity has powerful implications for many economic domains. It is an important determinant in the enforcement of contracts and social norms and enhances the possibilities of collective action greatly. Reciprocity may render the provision of explicit incentive...