Apparatus and method for the efficient utilisation of renewable energy

Apparatus and method for gaining maximum economic benefit from micro or small scale locally generated electrical power is disclosed. The apparatus includes a generator 8, a connection to the electrical mains 2, a diverter 7 to measure electrical parameters and switch power, and an energy storage means. When excess power is generated by local generator 8, it is stored, in preference to supplying the grid 2 at a credit rate much less than that at which power has to be bought, thus benefiting the local generator. The excess power may be stored either as electricity in batteries, heat in storage heaters or as hot water or as potential energy as pumped storage. The power energy stored may be used at a later date, when the power being generated locally is less that that required so that the shortfall does not have to be purchased from the grid. A key feature of the invention is that means are provided to utilise only small quantities of excess power, which would not be economic on larger scale generating plants. The excess power increments / decrements, which can be used due to changing generating levels, are equally small thus maximising the benefits for micro / small power generators.