Barry Lees (Letters, December 28) lists some of the renewable energy technologies that can be used for providing heat, but he omits the easiest and most obvious way of producing renewable heat: solar energy. This is a technology that simply converts light energy from the sun straight into heat energy.

It is already quite widely used across the world for heating water and buildings. So far, there are very few installations in Scotland.

This is despite the fact that recent research has shown that, surprisingly, Scotland has one of the best climates in Europe for using solar energy for heating buildings.

The reason for this is that our cool, temperate maritime climate allows us to use a much higher proportion of the solar energy we get than in countries further south, and this more than compensates for our relatively cloudy climate.

Solar heat has already been proved to be effective in tackling fuel poverty and cold, damp housing in several areas of Scotland - for example, Berwickshire and Perthshire.

Until now, solar energy has been Scotland's forgotten renewable. It's time that changed.