” Renewable energy can never be sufficient to power the planet, can it?.
The solar energy falling on our planet in one hour is greater than the energy from all the fossil fuels used by all of humankind in a whole year. Add in the energy of the tides, driven by the relative motion of the Earth and the Moon, and geothermal heat from deep underground, and it is clear that there is no shortage of renewable energy available to us.
The nature of renewable sources of energy is very different to the fossil fuels we currently depend on. Oil, gas and coal reserves are stored energy. Provided we can find them and extract them as fast as we want to use them, we can use as much energy as we like, when we like. We don’t, however, control when the wind blows. Weather forecasting gives us some idea, but if we don’t use the power of the wind when it is available, then we’ve missed it.
We need to change the way we think about energy to take account of these differences. We need ways of storing renewable energy in times of plenty for use in times of shortage, and more clever ways of using it so that demand is better matched to supply. Biomass fuel crops can store summer sunshine for use as winter heating fuel, but this brings with it many disadvantages. The electricity grid can work together with intelligent appliances to move demand for power away from peak times. But there remain some difficult areas, notably transport. There is no obvious successor to the vast quantities of easy-to-use liquid fuels that power our cars, buses and planes.
The important first step in this transition is to use less energy and to use energy more efficiently, in order to buy time to allow the supremely inventive species that is humankind to devise a safe route to our very different energy future. “
Alastair Sawday (2008: 47) What About China?