National Grid is looking for help to manage voltage levels in Mersey and South Wales and wants to hear what potential providers can do via a request for information.
The Electricity System Operator (ESO) intends to tender for services in 2019/20 and may also tender again the following year.
National Grid uses reactive power services to manage voltage stability on the network. As this is variable by location, it requires providers in specific areas to either absorb reactive power, which decreases voltage, or generate reactive power, which increases voltage.
The ESO said voltage control is harder to manage at demand extremes – both high and low. But it is currently planning to tender for services to manage only low extremes. Both the Mersey and South Wales documents state that providers must be able to deliver from 23:00 to 07:00.
The service will be open to both Balancing Mechanism (BM) units and non-BM units. The ESO wants to hear from companies that can provide services in both directions (absorbing and generating reactive power), as well as those that can only do one direction.
Providers are free to do other demand-side response services, provided these do not interfere with reactive power. Both availability and utilisation fees will be paid.