大觀二

Daguan No.2 Power Plant, situated within the same Sun Moon Lake hydro system as Daguan No.1 in Yuchi Township, Nantou County, is a pumped-storage facility. It pumps water uphill during off-peak periods and releases it to generate power at peak times, helping balance grid load.

Completed in 1985, Daguan No. 2, also known as the Minghu Pumped-Storage Power Plant, was Taiwan's first pumped-storage hydro facility, with four units totaling about 1,000MW. As solar generation has grown, its dispatch pattern has shifted from one pumping-and-generating cycle a day to two, typically pumping around midday and releasing water in the evening to cover the gap left as solar output fades.

大觀二 (Energy Storage) currently reports a net generation of -237.3 MW across 8 unit(s), against an installed capacity of 1,000 MW (-23.7% utilization).

This category mainly reflects discharge from battery energy storage systems, which can respond to grid frequency changes within seconds to minutes. It is used for automatic frequency control (AFC) and peak shaving, making it a key tool for grid flexibility as intermittent wind and solar capacity grows. Charging (the mirror-image "storage load") is tracked separately and is not included in this subtotal.

As wind and solar penetration rises, the grid's need for fast-response frequency regulation grows in tandem, making energy storage one of the fastest-growing categories in recent years — typically deployed as containerized battery units near substations or existing power plants. Storage capacity remains far smaller than gas or coal, but its role in maintaining grid stability is becoming increasingly important.