Renewable energy is expected to play a major part in future energy supplies, both to reduce the impact on the world climate and also to make up for any shortfall in conventional energy sources. Ocean energy has the potential to make a significant contribution to future renewable energy supplies as identified in recent reports from the Intergovernmental Panel for Climate Change and the International Energy Agency. Ocean energy is an emerging industry sector and there are a number of promising developments under way. Significant commercial deployments in the gigawatt range are envisaged over the next 10 to 20 years in Europe, USA, Asia and South America.