I HOPE that Brian Wilson (Letters, February 12) is wrong, as wind power has to be a critical element in the strategy to wean civilisation off fossil fuels and mitigate global warming.

That the global climate is in danger is evident in the disappearing ice in the Arctic – arguably the canary in the mine pointing to the presence of serious and unnatural global warming.

Mr Wilson states that wind power is a green myth because output is unreliable, being available only 25% of the time. This is true only of a single wind farm. Farms at opposite ends of the country operating at different times in different winds could have an aggregated output of 50%. Farms spread over the continent could in theory be generating power 100% of the time if enough were built. However, this need not be necessary.

Strategies are being formulated at the European level to co-ordinate the development of wind farms with solar farms using photovoltaic and reflector methods of generation, tidal power, wave power and geothermal power systems, all connected through a low-loss high-voltage DC grid system. At the engineering level it is already being envisaged that such a geographically diverse system could easily be backed up if necessary with massive energy storage systems based on pump storage hydro-systems, battery storage based on revolutionary lithium-air techniques and massive energy storage based on compressed air, to "fill-in" any power gaps that might occur in extreme conditions. There is no good engineering reason why a power supply system based wholly on renewables cannot be reliable and dependable.

Mr Wilson also suggests renewable energy would be grossly expensive under independence. There is growing evidence to suggest otherwise. Bloomberg New Energy Finance has released new research concluding that wind power in Australia is already cheaper than coal and natural gas. Cost superiority remained even when the price Australia charges polluters to emit carbon is discounted.

Alan J Sangster,

37 Craigmount Terrace,