"Swiss Army knife"-type deployments of energy storage, though often suggested, have seen little progress to date.
The idea is simple. If an energy storage project can be designed to provide multiple benefits and services, to tap more than one revenue stream, payback time is reduced.
The 6MWh/10MWh energy storage facility operated by distribution network operator (DNO) UK Power Networks, trialled in Leighton Buzzard, in southern England, remains one of a handful of storage installations that have been built to provide more than just one or two applications or services.
The main function of the Leighton Buzzard battery asset is peak shaving, which allows UK Power Networks to reduce peak times of electricity consumption to defer network reinforcement.
The battery bank also provides frequency response, enabling the transmission system operator, National Grid, to stabilise the frequency of the system, which is becoming an increasing issue as more variable renewable energy generation capacity is added and thermal generation capacity is taken offline.
It also provides electricity reserve, which helps to overcome the intermittency of renewable generation and tolling, where energy storage can offer wholesale market trading opportunities for other market participants.
Finally, the storage system has been designed to enable the delivery of additional, secondary services for the specific site.
These services include reactive power support and voltage support. All the primary and secondary services have been trialled in the project, funded through UK energy regulator Ofgem's Low Carbon Network Fund.
Advanced software architecture is required to manage and control the batteries within the energy storage system in order to provide the various different services.
Though many companies in the energy storage industry can build battery systems, there are fewer players providing the complex software architectures designed to enable energy storage systems to provide multiple services.
Grid infrastructure equipment supplier S&C built the system, which uses lithium ion battery modules from Samsung SDI, while German energy storage software developer Younicos wrote the controls for the asset.
Deployment
The Department of Energy (DoE) in the US, via its database of announced energy storage projects around the world, shows that while there has been a sharp increase of energy storage deployments since 2010, the majority of these tend to have no more than two purposes.
Between 2000 and 2010, out of 68 energy storage installations tracked by the DoE, 28 of these were registered as having two applications or functions, while 11 were registered as having one. Only three were built to provide three applications or functions.
From 2010 to date, of 227 tracked, 108 were built with two applications/functions, 83 with one application, and 27 with three.
Seven were registered with four applications/functions, including the project at Leighton Buzzard.
