In his letter, Jim Waterton (30 June) protests too much. If tidal energy cannot be allowed without the possibility and costs of storage being certain, how is it that nuclear has been allowed when the costs and feasibility of storing the used fuel for countless lifetimes is equally unknown and likely to be much higher?

He describes tidal energy as intermittent, when it is regular and very suitable as a base power source. In contrast, he describes nuclear power as consistent when this is far from the truth. Quite apart from their hopeless record on delivery dates, rising costs and concern that they will work, they’re also offline from time to time. The station at Sizewell is offline for maintenance for five to six weeks every 18 months. By November last year there had been 16 planned outages. But there had also been unplanned outages when dangerous faults have been identified.

The most likely, it seems the only, motivation for using nuclear power is its link to Trident. Electricity customers will be subsiding its cost. Prof Andy Stirling and Dr Phil Johnstone from the Science Policy Research Unit at Sussex University write that the £19.6bn Hinkley Point project will “maintain a largescale national base of nuclear-specific skills” without which there is concern “that the costs of UK nuclear submarine capabilities could be insupportable”.

Alicia Hull

Norwich

• It may suit the boss of Iberdrola to tell governments they should abandon “moonshot” green technologies such as the Swansea tidal project, but he should know better (Report, 2 July). Unlike wind and solar, tidal power is entirely predictable and, to a degree, can be stored within barrages and lagoons, providing greater flexibility.

Furthermore, tidal barrages can be used to improve transportation links across an estuary and help to manage flood risk which could be invaluable to the Severn estuary. Of course, there is an environmental impact but unless we get a move on, the world’s estuaries are going to feel the full impact of rising sea levels and warming waters. Tidal power is complementary to wind and solar which is why the British government should be looking to make the UK a world leader in the technology.

Liam O’Keeffe

Abinger Hammer, Surrey

• You should talk to people in the solar industry about the future for domestic solar power rather than just relying on “predictions” (Abandon wave power schemes, says energy boss, 2 July). As a non-executive director of AES Solar Ltd in Forres, Scotland, I can tell you that our order books are healthy, despite the government’s solarcoaster tariffs. We are seeing real, steady growth because, for instance, where better to spend a small part of a pension pot than to put in a solar water heater, PV electrics and a battery system, thus decoupling the household budget from soaring energy prices from the grid.

Smart householders don’t just switch energy providers, they go solar, not least those looking for a financially safer old age. That is the sort of compelling reason why solar has a brilliant future in the UK, not a dark one.

Emeritus Professor Sue Roaf

Heriot Watt University

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