- A proven technology pump storage has been utilized for more than a century in Europe and the U.S. as a utility-scale energy storage technology with low forced outage rates (<2%).
- Worldwide capacity of pump storage is more than 130 GW.
- Our projects can provide more than 1 GW of firm capacity and is the most compelling solution to the required increase in capacity and firm power production in B.C.
- Can alternate pumping and generating as required by BC Hydro. This provides BC Hydro with a versatile utility resource that can provide peaking capacity, ancillary services, arbitrage and transmission optimization.
- BC Hydro specifically named this technology in the 2012 Integrated Resource Plan as one of its Recommended Actions.
Pumped storage hydroelectricity (PSH) is a method of storing off-peak power and producing electricity to supply high demand by moving water between reservoirs at different elevations with the simple combination of water. At times of low electrical demand, typically at night, excess electrical capacity is used to pump water into the higher reservoir, turning electrical energy into gravitational potential energy. When there is higher demand, during the day time, water is released back into the lower reservoir through a turbine, generating electricity. Reversible turbine/generator assemblies act as pump and turbine.
PSH is the most widely used form of bulk-energy storage and currently accounts for more than 99% of bulk storage capacity worldwide: around 127,000 MW, according to the Electric Power Research Institute (EPRI), the research arm of America's power utilities.
Efficient technology to store electricity has become the "holy grail" for the power system as it copes with increasing production from intermittent sources such as wind and solar, and dramatic swings in demand. Some experts have dubbed storage the “missing link” that would allow renewable operators to generate their electricity under the most favourable conditions and dispatch it when it is needed most.
Example of Pumped Storage Power Plant:
Geesthacht Pumped-Storage Power Plant
Geesthacht Pumped-storage Power Plant was commissioned in 1958. The power plant is situated by the River Elbe and is the largest power plant of its kind in northern Germany.
The upper water reservoir, located almost 93 metres above sea level, is 600 metres long, 500 metres wide and has a water capacity of approximately 3.6 million m3. The plant has three turbines with a capacity of 40 MW each, giving a total capacity of 120 MW. After full discharge, the water is pumped up through three parallel pipelines to the water reservoir. The procedure of pumping up water and refilling the reservoir takes nine (9) hours.
- Energy source: Hydro
- Country: Germany
- Installed electricity capacity: 119 MWe
- Avg. annual electricity generation: 10 GWh
- Turbine type:Francis
- Head (m):80
- Water discharge (m3/s):66
- Year of commissioning: 1958
PSH are commonly used for load balancing in power systems. This generating and pumping cycle typically happens only once a day, and the overall efficiency is typically 85%. Our proposed modern pumped storage plants will be designed with fast start, load ramping and unloading capabilities. They can respond to load changes within seconds.
PSH, as opposed to thermal power stations, pumped storage power plants are able to react in the shortest possible time to network fluctuations, by generating the required electricity or by absorbing any excess. Modern systems need just thirty seconds to start the pumps or turbines up from a standstill. In the event of a power failure, pumped storage power plants can re-establish the power supply to the network without an external energy supply.
Pumped storage hydropower has a long history of successful development in the U.S. and around the world. Energy storage has been a part of the U.S. electric industry since the first hydropower projects, primarily through the flexible storage inherent in reservoirs. In the U.S., there are 40 existing pumped storage projects providing over 22,000 MWs of storage, with largest projects in Virginia, Michigan and California (Bath County, Ludington and Helms, respectively). Additionally, there currently are 51,310 MWs representing over 60 pumped storage projects in the FERC queue for licensing and permitting.
Globally, there are approximately 270 pumped storage plants either operating or under construction, representing a combined generating capacity of over 127,000 megawatts (MW). As a proven technology, it been shown to be cost effective, highly efficient, and operationally flexible. This grid scale storage technology has been used extensively to both store and redistribute electricity from periods of excess supply to periods of peak demand and provide grid reliability services in generation mode. Similar to the U.S., European energy policy is also focused on adding clean, renewable energy to the grid. And the significant amounts of wind and solar being brought on-line is the motivating force that is driving new pumped storage development noted above