Pumped storage hydropower (PSH) is a kind of hydroelectric vigor storage that uses a system of two interconnected reservoirs at different elevations to store and generate electricity. During periods of low electricity demand, surplus electricity is used to pump water from the inferior reservoir to the upper reservoir. When electricity demand is high, water is free from the upper tank to the lower reservoir, passing through turbines to generate electricity.
PSH is the most mature and widely deployed energy storage technology in the world, with a global capacity of over 160 gigawatts. It is a
highly efficient and reliable technology, with round-trip efficiency of up to
85%. PSH plants can also respond quickly to changes in electricity demand,
typically within minutes.
PSH plays an important role in supporting the transition to
a clean energy grid. It can help to integrate intermittent renewable energy
sources, such as solar and breeze power, into the grid by storing excess
electricity when these sources are generating at high levels and releasing it
when demand is high. PSH can also help to improve grid reliability and
resilience by providing backup power and frequency regulation services.
Here are some of the key benefits of pumped storage
hydropower:
High efficiency: PSH has round-trip efficiency of up to 85%,
meaning that it can store and retrieve electricity with relatively little loss.
Fast response: PSH plants can respond to changes in
electricity demand within minutes, making them ideal for providing backup power
and frequency regulation services.
Large storage capacity: PSH plants can store large amounts of energy, making them well-suited for supporting the integration of
intermittent renewable energy sources.
Long lifespan: PSH plants have a lifespan of typically
50-100 years, making them a long-term investment in energy infrastructure.
PSH is a versatile and important technology for supporting
the transition to a clean and reliable energy future.
What is pumped hydro energy storage system?
A pumped hydro energy storage system (PHES) is a type of
energy storage system that uses a system of two interconnected reservoirs at
different elevations to store and generate electricity. During periods of low
electricity demand, surplus electricity is used to pump water from the lower
reservoir to the upper reservoir. When electricity demand is high, water is
released from the upper reservoir to the lower reservoir, passing through
turbines to generate electricity.
PHES systems are the most mature and widely deployed energy storage technology in the world, with a global capacity of over 160 gigawatts. They are highly efficient and reliable, with round-trip efficiency of up to 85%. PHES plants can also respond quickly to changes in electricity demand, typically within minutes.
PHES systems play an important role in supporting the
transition to a clean energy grid. They can help to integrate intermittent
renewable energy sources, such as solar and wind power, into the grid by
storing excess electricity when these sources are generating at high levels and
releasing it when demand is high. PHES can also help to improve grid
reliability and resilience by providing backup power and frequency regulation
services.
The key components of a PHES system are:
Upper reservoir: This reservoir stores water at a higherelevation.
Lower reservoir: This reservoir stores water at a lower
elevation.
Pump-turbine: This machine can both pump water uphill and
generate electricity by spinning a turbine as water flows downhill.
Penstocks: These pipes connect the upper and lower
reservoirs to the pump-turbine.
During the charging cycle, electricity is used to power the
pump-turbine to pump water from the lower reservoir to the upper reservoir.
During the discharging cycle, water is released from the upper reservoir to the
lower reservoir, passing through the pump-turbine to generate electricity.
PHES systems are a versatile and important technology for
supporting the transition to a clean and reliable energy future. They offer a
number of advantages over other energy storage technologies, including high
efficiency, fast response, large storage capacity, and long lifespan.
What is pumped storage used for?
Pumped storage is used for a variety of purposes, including:
Energy storage: Pumped storage can be used to store excess
electricity made by renewable energy sources, such as solar and wind power,
when these sources are generating at high levels. This electricity can then be
released when demand is high or when renewable energy generation is low.
Grid balancing: Pumped storage can be used to help balance
the electricity grid by providing backup power when demand is high and
absorbing excess electricity when demand is low. This helps to maintain a
stable frequency on the grid.
Frequency regulation: Pumped storage can be used to provide
frequency regulation services, which help to keep the frequency of the
electricity grid within a narrow range. This is important for the reliable
operation of the grid.
Black start capability: Pumped storage plants can be used to
black start the electricity grid after a major blackout. This is because they
do not need external electricity to start up.
Pumped storage is a versatile and important technology for
supporting the transition to a clean and reliable energy future. It can help to
integrate intermittent renewable energy sources into the grid, improve grid
reliability and resilience, and provide black start capability.
Here are some examples of how pumped storage is being
used around the world:
In the United States, pumped storage is used to support the
integration of solar and wind power into the grid. For example, the Bath County
Pumped Storage Station in Virginia is used to store excess electricity
generated by solar and wind power in the day and release it in the evening when
demand is high.
In China, pumped storage is used to support the country's
rapid economic growth and to reduce its reliance on fossil fuels. For example,
the Guangzhou Pumped Storage Power Station in Guangdong Province is the largest
pumped storage power plant in the world, with a capacity of 2,400 MW.
In Europe, pumped storage is used to support the integration
of renewable energy bases into the grid and to improve grid reliability. For
example, the Dinorwig Power Station in Wales, UK, is the fourth largest pumped
storage power plant in the world and plays an important role in supporting the
UK's electricity grid.
Pumped storage is a key technology for enabling the
transition to a clean and reliable energy future. It is a versatile and
efficient technology that can be used to store energy, balance the grid,
provide frequency regulation services, and provide black start capability.