We actively manage the electricity distribution network as real-time configuration determines whether or not it is necessary to limit a customer to their firm Authorised Supply Capacity (ASC). The following are key factors in determining when and how we actively manage the network:
- the level of generation export capacity is determined by the real-time configuration of the distribution network
- some customers have both a firm authorised ASC and a non-firm ASC, which is usually larger
- if customers export excess generation capacity to the network, we make arrangements for output to be constrained between zero and their full ASC.
During fault conditions some customers may be requested to restrict their usage, until the network is once again reconfigured and allow their normal load to return.
Auto Load Reduction Schemes (ALRS)
ALRS are employed at some sites to protect the plant and long-term supplies to customers.
- only operate when some of the plant at a site is out of service
- shed load to within the capability of the remaining plant in service at a site
- recognise the real time loadings on the system.
Load Managed Areas (LMAs)
LMAs are sections of the network where special arrangements are in place to manage security and continuity of supply.
LMAs are designated in accordance with the provisions of the electricity distribution use of systems agreement.
Currently there are no LMAs in use in the Electricity North West region.