Analysis: Placing a nation’s power production at the mercy of the weather looks unrealistic

Renewables are very dependent on weather and are subject to all the variations we get with wind and rain over the course of a year.

These new figures suggest that we could be left with a great problem if we were to rely completely on renewables.

There’s a real risk if you get a dry year for example. In that case there would simply not be enough to create the renewable energy needed.

We could easily fall short of the targets for 100 per cent renewables, which suggests that it is too narrow a vision to base an energy policy solely on renewables.

Having a system of relying on rainfall and wind power for a nation’s energy needs is always going to be at the mercy of the elements and a decline in the amount of renewables generated will happen from time to time.

A specific example of the problems associated with this approach is that of Denmark, where the country has targets for generating a large share of its electricity from wind.

Again because of the dramatic variations in the weather, Denmark produces wind power at the wrong time of the year, when there is less of a need for electricity. Denmark ends up selling it to other countries at a financial loss.

There is a real need to have a more realistic energy policy than that of a 100 per cent target for renewables.

The differences in weather year on year mean that the amount of renewable energy produced will also vary from year to year, which would create serious problems for a nation’s energy supply.

Investing more in renewables will help with the targets, but the effect of the weather means it is always going to be problematic and lead to uncertainty.

• Martin Livermore is director of the Scientific Alliance.