A pumped storage hydroelectric generating facility can produce large amounts of electricity, generally during valuable peak periods, in a matter of seconds. This helps to eliminate the need to have expensive and inefficient base load generating plant in continual operation should the need arise due to a sudden increase in demand, plant breakdown or to regulate the network frequency. Then at night, or during low energy demand periods, the plants reverse pumping operation provides a high demand for electricity which allows the large base load power stations to operate on a more continuous and efficient basis or underpins load for variable renewable generation.
The spinning reserve capability of a pumped storage power station is its unique ability to be on standby (within seconds) ready to respond to a sudden loss of generating plant already supplying to the grid, or to compensate for a rapid increase in demand. This unique capability will displace the more expensive and inefficient method of currently maintaining the system reserve. The current method of providing standby capacity to the system is by operating partially loaded coal fired power stations over many hours during low system demand and at great expense.
The environmental benefits to the community by possibly preventing the construction of the next large gas peaking plant – thus eliminating the potential emission of greenhouse gasses from that plant. Additionally, when combined with a variable renewable generation plant, the pumped storage power station provides a portfolio levelising capability through storing high renewable energy generation and releasing during high market events. By installing a pumped storage generating facility capable of providing significant quantities of reliable peaking power, there is the ability to allow the base load stations to operate at full capacity around the clock without having to worry about plant redundancy levels for standby situations. The standby capacity or spinning reserve and peak load supply of electricity can be provided by a pumped storage power station.
Pumped storage power stations have the ability to provide “Black Start” capacity to the network. This means a pumped storage facility can be designed to be self sufficient during plant start up or following an electrical blackout when there is no external support power for excitation. This has the benefit of allowing the plant to be totally reliable during system failures, blackouts or even as a support to major base load power station which rely on external power sources for plant start up.
There are additional markets for pumped storage power stations to participate in to assist the stability of the grid, namely the ancillary markets which cover frequency control, network control and system restart services. These markets are well suited to the fast response and desirable electrical characteristics of a pumped storage power plant.