The generation game

Steve Pester, BRE, looks at how energy storage is rapidly growing in importance and how we can harness this fledgling technology

With government predictions of electricity prices of 19p per unit by 2020, the rewards for using any electricity that has been generated on site can only increase. As mentioned in a previous article, ‘storage’ is the latest buzz word. At a domestic level, that generally means batteries, perhaps also with a little heat storage in the hot water cylinder.

In Europe, and increasingly in the UK, the term ‘self-consumption’ is the next buzz word to learn after storage. This has nothing to do with ‘consumption’ as the Victorians would have known it, but everything to do with becoming a little more independent from the utility companies.

The claims are that when used with an intermittent energy source such as PV or wind turbines, battery systems can increase the self-consumption of a household (that is the amount of on-site generated electricity that is consumed on site, rather than being exported to the grid) from about 30 up to 60 per cent. These figures, whilst not unreasonable, depend, of course, on a number of factors such as usage patterns, battery bank size, micro-generator size, etc.

Whatever the exact figures, the technology will most likely induce both excitement and fear. It’s an exciting prospect for early adopters, people keen to become as independent as possible from the utility companies and for battery manufacturers, for obvious reasons; but also for the DNOs and National Grid. If deployed in large numbers, local storage could be a very useful tool in helping to balance the supply and load on the grid and in reducing the peaks in demand. One can imagine that the electricity suppliers might be a little more uncomfortable with the prospect of people being able to supply more of their own power.

Either way, there is the usual danger of a quickly developing, unregulated market springing up with every man & his dog becoming overnight storage experts. With this is mind, the BRE National Solar Centre will be looking at storage technologies in due course and will provide some level-headed guidance. If implemented carefully, we think there is a very strong future for microgeneration/storage combinations – with prices dropping fast, it will knock down the final argument of the renewable energy critics. www.bre.co.uk/nsc