Wind and solar generation is treated as priority dispatch (per SONI and EirGrid licences, SEM Committee decision SEM-11-062 and subsequent mods) however it is sometimes necessary to constrain or curtail its output to maintain system security. Constraints result from power flow limitations due to the topology and characteristics of the transmission network. Constraints are applied locally. Curtailment arises due to binding all-island system wide limits such as the System Non-Synchronous Penetration (SNSP) limit or minimum inertia levels. Curtailment is applied Al-lIsland.
We use the Wind Dispatch Tool (WDT) in the TSOs’ Control Centres to manage wind/solar constraints and curtailment in real time operation of the power system. The WDT allows the application of active power (MW) limits to the outputs of individual, controllable, wind/solar farms. While curtailment is applied globally to all wind/solar farms, constraints are applied to individual wind/solar farms or groups of wind/solar farms associated with the constraint.
This document provides an overview of the main wind/solar constraint groups for Ireland and Northern Ireland that are currently defined in the WDT. We plan to review the Wind Dispatch Tool constraint groups on a regular basis. We want to work in partnership with industry and welcome any feedback that you may have for consideration in future iterations. Please send feedback on this document to info@eirgrid.com or info@soni.ltd.uk.