Steve Emsley is wrong when he compares tidal lagoons with Hinkley and asks why tidal energy is not even being discussed (Letters, 17 August). The latest estimated cost of the lagoon proposed for Swansea Bay is £1.3bn. Hinkley would produce 65 times as much electricity, all day, every day – true “baseload”. Tidal lagoons would produce variable amounts (four times as much on a spring tide as on a neap tide in Swansea and a bigger difference further up the Severn estuary) and the generation would be intermittent (four three-hour blocks a day) – that’s not “baseload”.
Lagoons could only produce 8% (about 25TWh a year) of the UK’s electricity requirements (a figure challenged by tidal energy experts), if five others followed Swansea, each many times larger and much more costly than Swansea (many times more than £5bn in total). But consent for the next two (huge lagoons further up the Severn estuary off Cardiff and Newport) is most unlikely because of various EU environmental designations (special area of conservation, special protection area etc). As to why no one is discussing them: in fact, Charles Hendry is conducting a review of tidal lagoons to assess, among other things, whether they could play a cost-effective role in the UK energy mix (see www.hendryreview.com). Some think the review was prompted by belated government realisation that the figures bandied around for lagoons just don’t add up.
Phil Jones
Ynystawe, Swansea
• The crown estate’s support for wind power and tidal energy (Report, 15 August) must receive full backing from government and public, in spite of any commitments to Hinkley Point. Zero-carbon economies must be top priority worldwide. Wind is already making a substantial contribution to renewable electricity supplies, in this country and elsewhere, but tidal energy seems to have been overlooked. Yet it is safe, sustainable, dependable, available at many places round our shores and in the wider world. It is also much cheaper and less obtrusive than Hinkley Point and similar projects.
Elsa Woodward
High Wycombe, Buckinghamshire
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