Sustainable energy development requires attention to both the demand and supply side. On the demand side there is an urgent need for efficient policy means promoting energy conservation. This includes changes in the institutional and economic framework to compensate for the short comings of the dominating neoclassical economy and the short time horizon of the present market system. On the supply side fossil fuels are becoming a central problem being the dominating global energy source while at the same time presenting serious problems in relation to global warming and limited resources (“peak oil”). Consequently, there is an urgent need to develop alternative strategies and policy means in order to promote sustainable development.