Abstract
George Plester's letter on the problem of intermittency in electrical supply from wind has been overstated. The generation and distribution system is designed to cope with rapid unpredictable changes in demand, so it can cope with slower and predictable changes in supply from one particular source. With regards to geographical averaging, the variations in output are damped on a UK-wide scale. It is a mistake to see any energy source in isolation from others in the system. For example, CHP plant can provide a spinning reserve with the power output variable to back-up variable souces like wind. The overall conclusion should look at the whole ssytem and how individual components fit into it.