Wave and tidal power could provide enough cheap energy for up to 15 million homes in Britain, the government has said.
According to energy minister Lord Hunt, the clean cheap energy generated by hydropower could help reduce emission levels and secure Britains future energy supplies.
It is estimated that up to 70 million tonns of carbon dioxide could be saved by 2050 if marine energy is fully exploited, while as many as 16,000 jobs could be created.
Speaking at Strangford Loch in Northern Ireland, Lord Hunt said: "Harnessing the power of our seas will help us reduce our carbon emissions, provide clean, green, secure and reliable energy, create jobs and provide export opportunities.
The government has unveiled its Marine Energy Action plan, which sets out its vision of marine energy projects around the UK.