Hope springs eternal in the UK where groups are trying to revive the Severn tidal power project - Severn Tidal Power Subsidy Below Offshore Wind. The article says the subsidies required to be similar for those for a new nuclear power plant - but for a 30 year time frame, even though the tidal power plant would work for well over a century (and wouldn't have unquantifiable decommissioning costs).
The Severn Barrage project probably will require subsidies at about the same level as nuclear power stations and less than what’s offered for offshore wind plants, the developer of the British tidal energy project said.
“We expect that the price we will be able to negotiate will fall below offshore wind, and we hope close to or perhaps at the price nuclear power is currently negotiating,” Gregory Shenkman, chairman of Hafren Power Ltd., said at a hearing in the House of Commons in London today. That would make the project economically viable, he said.
The comments are aimed at answering the criticism that the technology that’s not working at a commercial scale anywhere in Britain would cost too much. Estimates for what the dam-like structure spanning the river at the southern end of Wales ran up to 25 billion pounds ($39 billion).
The Hafren plans, put to Prime Minister David Cameron in July, involve an 11-mile (18 kilometer) barrage from Cardiff in South Wales to Weston-super-Mare in Somerset. Its 1,026 turbines would generate power on tides as the sea rises and falls. The project may create about 20,000 construction jobs and 30,000 manufacturing and service jobs.
The barrage could fulfil 16 percent of that target and be capable of generating as much as 5 percent of the U.K.’s power, the government estimates. The project would need 30 years of support through subsidies. Thereafter, it would run for at least 90 years without support, generating electricity that’s 75 percent cheaper than all other forms of generation, Shenkman said. Across its 120 year life span, the project could produce power at about 48 pounds-a-megawatt-hour, less than the 88 pounds nuclear power costs, he said.