The System Operator says it still regards rolling power cuts for consumers as ‘unlikely’ over the coming weeks but the possibility that they will be required means suppliers and network companies are going out to brief customers on how such action would affect them.
The companies are urging their customers to ‘make a plan’ in case the system operator has to ask networks to cut their supply.
What UK Power Networks described as ‘power sharing’ rotas would be employed in the event supply was unable to meet demand. It would see the power cut for three hours for a proportion of customers. The local distribution network operator will carry this out. Its customers are allocated to a ‘block’ identified by an initial letter and partially determined by network structure. There are 20 blocks and they would be cut on a rota, so power outages should be extremely infrequent to any single group of customers. Each ‘block’ is not a single area, but a number of small areas across the region.
A planned power cut of up to three hours for a block would be signalled 12-18 hours ahead of time. The need to cut power is likely to be for short periods, such as the peak hours (typically 5-7pm).
For some consumers, such as those in rural areas where the grid is relatively vulnerable and more affected by storms, customers may have experienced blackouts of three hours or more during a stormy winter and be prepared for a similar event. Customers in cities and areas where outages have been less likely may not be prepared.
The option to cut customer supply is a longstanding part of the options for managing the system in the event of emergency. Some key installations are excluded from the cuts and it is assumed that many large organisations for whom power supply is ‘mission critical’ will have their own backup power supply arrangements. However consumer groups have raised concerns over individuals who have a critical need for domestic power, such as those with medical equipment at home, will be supported in the event of a power cut, or how other vulnerable customers will be supported.
Stakeholder groups also raised concerns that for many customers other key services like phones or heating systems would not be available during a power cut.

UK Power Networks asked its customers to prepare as follows:
Find the property’s ‘block’ letter (and rota, when published) at www.powercut105.com
Save 105, the free national power cut emergency number
Keep a mobile phone fully charged to use for updates or calls
Remember that your gas boiler, heat pump, broadband and cordless home phone will not work without electricity