This paper presents three different types of certificates ('white' for energy savings, 'green' for renewable electricity, and 'black' for greenhouse gas reductions in the European Emission Trading Scheme). The current limited experiences with these instruments already allow to define some of the success factors for these new instruments. A synthesis of their current application presents how much energy is saved today due to these certificates, and how much green electricity is produced. A discussion on the methods for setting the targets, measuring the impacts on the market and the interaction between these different instruments concludes this paper, followed by a reminder of the proposal to create an international agency on global stewardship for climate change issues.
