For many the emerging energy storage technologies and in particular battery storage are seen as the key to transforming the renewables industry and providing a realistic solution to controlling supply to / managing demand from the grid.
We have all driven past wind farms which lie dormant as their production capacity has outstripped the power which can be either consumed locally or drawn-off to the grid.
With National Grid (as the UK system operator) currently paying wind farms to stop generating at times of lower demand, it is easy to see why potential solutions for converting the unpredictable output of solar and wind generators into a dependable and affordable supply are seen as the future of the renewables industry.
While part of the solution will involve managing demand to minimise electricity use when supply is scarce, it is likely that the largest contribution will come from storing energy in batteries when weather conditions are optimal and then releasing it to the grid as demand dictates.
Indeed the market is seeing increasing interest in retro-fitting battery storage to existing sites and also planned as part of new developments.
However the potential for battery storage goes further than just assisting with the generation of renewable power. Battery storage solutions can provide a fast discharge of power and restore system stability to the grid, thus providing ancillary services to grid operators by way of frequency regulation.
In additional battery storage can also reduce exposure to imbalance charges for balancing system participants. It can also reduce the need for load-related investment in electricity networks by National Grid and District Network Operators (DNO).
The Secretary of State, Amber Rudd, has said that storage represented a fantastic opportunity for the UK and was a necessary partner to renewable generation to create a secure system. Yet the question needs to be asked, what is holding back energy storage in the UK?
The Energy Storage Operators Forum highlights several key issues:
There are also questions around how current regulation allows a DNO to maximise the return on investment of its battery storage assets (using the assets in electricity trading, capacity and balancing markets during those times when the asset is not required); and whether this would mean that the DHO is in breach of the requirements of its distribution licence.
Lastly are considerations around cost. Whilst the costs are coming down as new developments in the technology emerge, at the moment the costs may prove to be a barrier to wide scale implementation.
However the UK is definitely looking towards battery storage solutions. Indeed National Grid, through its Enhanced Frequency Response tender has identified the opportunity as one which would be of particular interest to battery storage developers. In this instance developers will be looking to deploy battery storage at stand-alone sites. These units will be used to help balance demand – taking power from the grid when demand is low and releasing power back to the grid when demand is high.
It will be interesting to see whether the programme, and the knowledge that involvement in it will bring developers, will provide a catalyst for further roll-out of battery storage on existing or planned renewables projects.