I'm a retired electrical engineer with many years experience working in public and private parts of the electricity supply industry, so I can't resist responding to Anthony Reeve's letter last week which commented on G W Sankey's advocacy of under-sea turbines and then urged the alternative merits of solar power.

Mr Sankey was right to suggest that electricity generation using sea currents, tidal power or wave power could provide renewable energy that is more reliable, much more cost-effective and more predictable than grossly over-hyped wind generators.There are a few developed schemes already in operation around our coasts, but, sadly, privatisation of the supply industry almost stopped R and D work on such systems completely, and lack of government drive still limits progress. But one day such schemes will form a really valuable part of an integrated supply system together with solar and nuclear power, some gas (CCGT) systems and maybe even some wind generators if they haven't all fallen down by then.

However Anthony Reeve's idea of distributed local solar power schemes as a means of eliminating transmission networks is nonsense.

Transmission systems are there to ensure reliable, continuous and cost-effective electricity supply to us all by pooling the outputs from the nation's sources of generation, not as a profit-making device for grid system operators. A simple, back-of-envelope calculation shows that multitudes of fragmented local solar power systems can never provide, even in daylight, the quantity of electric power that we need as an industrial country, never mind the unreliability of such an arrangement. And the problem of storing the power overnight is almost insurmountable.

No, what is needed is an interconnected system using a range of generating plants which do not produce greenhouse gases. And to continue developing such a system requires an integrated engineering approach which we are not going to get so long as we have governments that believe "leaving it to the market" will solve all our problems.

– David Norman, Longhope.