Emergency reserve from flexible loads and impact on existing plant portfolio

This paper focuses on the use of flexible loads for providing emergency reserve to manage wind variability for a weakly interconnected power system. Ramping restrictions and starting costs of existing reserve facilities prompt research work on reserve from load. Flexible loads can be switched off quickly during under-frequency transients to maintain stable frequency and operation of the power system. Controlled heat pumps could be very helpful for providing a quickly available system reserve resource for regulating system frequency and hence system security and reliability. Different scenarios have been used to include the reserve from load and these scenarios have been used to schedule the Irish power system using the WILMAR planning tool for the year 2020. Considering a likely correlation of wind power expansion in both Irish and GB systems, the system operation cost, capacity factors of different technologies and the number of start-ups have been compared for reserve scenarios with and without an interconnection to the GB System. Finally, the reserve from flexible loads has been used to replace equivalent open-cycle gas turbine (OCGT) capacities and the results are compared for the defined scenarios.