What’s to like?

You ask “What’s not to like?” about generating electricity from solar panels (Comment, 4 July). Well, the cost for a start. The average domestic solar PV system is 4kWp and costs £5000-8,000 (including VAT at 5 per cent). Not everyone has that spare cash. Moreover, PV is not competitive without the subsidy it presently receives and will not be until it generates at least 1.5 times the energy used in its installation.

The UK government calculates that the electricity generated by a 4kW installation costs £310/MWh (total levelised). That’s about three times that of conventional hydro 
power or onshore wind farms.

Apart from all that, all forms of renewable electricity generation are a headache for the grid controllers, charged with maintaining an adequate electricity supply at the right frequency. They have no control 
over these scattered generating inputs and so have to ask thermal stations (except nuclear) to come on and offline to balance the load on the network. That makes these thermal stations inefficient, and likely unprofitable. While the output from wind farms is wind-dependent, PV is sun-dependent and so is useless at night. Until efficient means are found to store electricity at a reasonable cost, all renewables will suffer these defects.

Steuart Campbell

Dovecot Loan

Edinburgh