The recent weather and resulting power cuts have brought home to many people that even if you have a renewable energy source for your house, you generally need an incoming power source to enable it to work. PV invertors need a synchronising supply, heat pumps need a supply and even your gas central heating and many gas fires need an electricity supply in order to function. The intermittent nature of many renewable supplies such as PV and wind means that a method of energy storage would be very useful. If you have a biomass system or a heat pump, you may have a thermal storage tank which can maintain hot water supplies for many hours without input, however they still require power for the pumps!
A battery storage system would be very useful which could be charged up when renewable energy is produced and then could be used when the external source is not available. I have not seen much evidence of these systems in the UK apart from with off grid PV systems where large batteries are charged from a solar PV array. I am sure this could be extended, admittedly at some cost, to a grid connected system. I understand that this is already available in Germany, why not here?
Work has recently started on the production of an international energy storage standard for use with Smart Grids. This should encourage micro storage systems in individual premises. A draft may be available later this year or early next year.
Under the current FiTs arrangements export payments may be still payable with storage installed. A true win-win situation.