Ancillary services in Taipower
In keeping with global trends, the Taiwanese government is making every effort to promote renewable energies. The Taiwan government amended the Electricity Law in 2017, setting a target of 20% of electricity from renewable energy, 50% of natural gas, and 27% of coal-fired power plants and other resources.
In order to integrate a large amount of renewable energies and remain the system’s stability and reliability, Taipower has adopted four different types of ancillary services, including Fast Response, Regulation, Spinning Reserve, and Supplemental Reserve to cope with the uncertainty, intermittence and uncontrollability of renewable energies.
The challenges of the new era should be solved with new technologies. Taipower plans to introduce nonconventional resources such as energy storage systems, demand response and other fast response power generation resources to increase system flexibility.
Beginning in April 2020, Taipower has implemented the "non-traditional generators providing spinning reserve ancillary services" mechanism and introduced external resources to help adjust the system frequency. By the end of 2020, a total of 33MW of aggregator, energy storage, and self-use power generation equipment have participated. They can respond quickly to services within 30 minutes and provide power support for the system for 60 minutes.
Taipower has purchased 30MW high-efficiency ancillary services in 2020: "Automatic Frequency Control (AFC) Ancillary Services for Energy Storage Systems" and "Fast Response Load Resource (FRR) Ancillary Services". AFC and FRR ancillary services can assist the system to adjust the frequency in real time, maintain system stability and prevent the frequency from falling below 59.5Hz (normal state is 60Hz) causing under frequency load shedding (UFLS). Both cases are currently under construction and testing and are expected to be completed in June 2021.
The Taiwan government is currently piloting a market mechanism to obtain various ancillary services required by the system. Taipower is cooperating with the "Key Points for Setting Up a Trial Platform for Ancillary Services and Reserve Capacity Trading" announced by the Ministry of Economic Affairs on December 24, 2020, to establish a pilot platform for the ancillary service market. This trial trading platform is expected to be launched in 2021.