05 May 2010 10:05:10
What are the most promising energy storage solutions for the UK?
As the UK increases its use of renewable energy sources, the need for effective storage becomes greater.
While there is a consensus that a cost-effective, reliable and efficient system is needed, there is nothing like an agreement on what this system will be.
The Department of Energy and Climate Change recently awarded over £7 million to eight different firms to be spent on the creation of so-called smart technologies, including storage solutions.
Over in the US, the Advanced Research Projects Agency (ARPA) has provided even more funding, with $106 million (£68 million) going to 37 different projects, including some companies which are developing new types of batteries.
And this is not to say that there are not currently options out there for the storage of energy harvested from renewable sources.
Pump storage systems, like the one installed at Dinorwig power station in Wales, is one option which is already used when there is significant demand on the national grid. The pump storage system allows the generators at the plant to reach their maximum capacity in less than 16 seconds.
However, as the system works by transferring the water between two lakes situated at different elevations, the usage of pump storage is hugely dependent on an area's geography.
Hydrogen represents another opportunity. However, the element itself can be tricky to store, limiting its usage, although it is still used as a second source of power to some electric cars.
Earlier this year, a group of scientists claimed that by applying an electrical field to the storage material, hydrogen will be easier to store, but as of yet this is still highly theoretical and a long way from being a practical solution.
The development of batteries is one of the areas targeted by the ARPA funding. Projects include the development of batteries for electric vehicles and the creation of a hybrid storage system which is somewhere between a rechargeable battery and a fuel cell.
Both of these are hoping to overcome one of the fundamental issues with using batteries as a form of energy storage - the high cost.
In addition to all of these there is compressed air and new theoretical approaches, such as the gravel batteries which would compress and expand gas to store energy.
But with so many systems displaying such a range of pros and cons, is it yet possible to tell which are likely to be the biggest players in the UK's energy future?