by Dave Elliott
There has been a renewed push for a Severn Tidal Barrage, but, as I have reported in earlier posts, many saw it as too big to fund and too invasive to allow. Dr Nicholas Yates from the National Oceanography Centre, who has carried out the research with a team at Liverpool University, has backed smaller barrages, which he suggested could supply 15% of UK electricity. He told the BBC: ‘I think it’s unfortunate that attention for tidal range has tended to focus on the Severn, it’s the wrong place to start, it’s too big. Start small, it’s what the Danes did with wind – start small, learn quick and build up.’
By Dave Elliott
Tidal energy is developing relatively slowly, but has a significant potential. Although two large tidal barrages now exists (with 240 MW units in France and South Korea), the emphasis is on free-standing tidal current turbines, which harvest the horizontal flow of the tides, rather than trapping tide rises behind dams, as with barrages. So the environmental impact is likely to be much less. They can also be installed relatively quickly, one by one, so reducing project finance problems. The 6th Tidal Summit, organised by TidalToday in Nov 2012, reviewed the scene, with a key issue being the need to get costs down. DECC said they has to get to down below £100/MWh by around 2025.
By Dave Elliott
The report on the Severn tidal barrage from the Select Committee on Energy and Climate Change concluded that the proposal for a £25bn privately funded barrage from Hafren Power was not convincing and lacked detail. Hafren Power had “failed to overcome the serious environmental concerns that have been raised” and had “failed to reassure the ports industry that its business would continue to be viable with a barrage in place”. It went on, “while a tidal barrage could offer decarbonisation and energy security benefits, the Hafren Power project in its current form has not demonstrated sufficient value as a low-carbon energy source to override regional and environmental concerns. Alternative pathways exist to meeting our 2050 carbon targets.” It added that “alternative options for exploiting Severn tidal resources also exist” and it looked at some of them briefly, including the 250–350 MW Swansea Lagoon proposal, the 600 MW “Stepping Stones” Lagoon put forward by Parsons Brinckerhoff/Black & Veatch, and also Rupert Armstrong’s 6 GW Tidal Reef concept.