by With the increasing reliance on renewable energy sources like solar and wind, the need for large-scale energy storage solutions has also grown exponentially. Pumped hydro storage is one of the most viable options available to store excess electricity generated from renewable sources and utilize it when demand is high.
How Pumped Hydro Storage Works
Pumped hydro storage relies on the simple principle of using excess electricity to Pumped Hydro Storage water from a lower reservoir to an upper reservoir. When electricity is needed, the stored water is released from the upper reservoir through turbines to generate hydroelectric power. It works very similar to conventional hydroelectric power plants with an important difference – the water cycle is reversible here.
During times of low electricity demand and high renewable energy output, surplus power is used to pump water from the lower reservoir to an upper reservoir, which may be atop a mountain or hill. The water stored in the upper reservoir is held at high potential. When power is in high demand and renewable supply is low, the water is released back down through turbine generators installed between the upper and lower reservoirs. This generates electricity to meet the peak demand.
Advantages of Pumped Storage
Pumped hydro storage has many advantages that make it uniquely suited for large-scale energy storage needs:
Capacity – Pumped storage plants can store massive amounts of energy. Each plant can store thousands of MWh of electricity, enough to power tens of thousands of homes for hours.
Efficiency – Pumped storage systems are around 75-80% efficient, meaning 3/4th of the energy stored can be recouped. This is far higher than other storage technologies like lithium-ion batteries.
Lifespan – Pumped storage facilities are designed to last for over 100 years with minimum maintenance required. This makes the technology economically viable over decades of use.
Flexibility – Pumped storage can discharge electricity very quickly within minutes to adjust to shifting supply-demand cycles better than other alternatives like natural gas plants.
Resource Abundance – The geography and locations needed for upper and lower reservoirs are widely available across the world. This ensures easy scalability of the technology.
Existing Projects and New Developments
Major Projects Globally
There are over 200 pumped storage plants worldwide with an installed capacity of over 150 GW. The largest markets have been USA, Japan, Spain and Germany which have several multi-gigawatt capacity stations. Some notable projects are –
Bath County Pumped Storage Station in Virginia, USA (3.03 GW)
Dinorwig Power Station in Wales, UK (1.7 GW)
Okuyoshido Pumped Storage Power Station in Japan (1.38 GW)
India’s First Pumped Storage Project
India is increasingly recognizing the strategic importance of pumped storage and has launched several projects recently. The first commissioned project is the 1000 MW Kadamparai Pumped Storage Project located between Kodai Hills and Kundah Hills in Tamil Nadu.
Future Outlook
With energy transition in full swing globally, pumped hydro storage deployments are expected to accelerate even more over the coming decades. The IEA forecasts the global pumped storage capacity to grow from roughly 160 GW today to above 400 GW by 2050. Emerging economies like India are well-positioned to take advantage of their geography and hydro resources to deploy large volumes of clean, cost-effective pumped storage capacity. Developments in areas like closed loop systems can also expand possible locations beyond natural upper and lower reservoirs.
Pumped hydro storage provides a proven, reliable solution to store vast amounts of renewable energy output for use during periods of peak demand. Its long lifespan, efficiency, scalability and flexibility make it vastly superior to alternative storage technologies currently available at utility-scale. As the world moves to increase the share of renewable energy on the grids, pumped storage growth will be crucial for a stable, low-carbon electricity system of the future.
Note:
1. Source: Coherent Market Insights, Public sources, Desk research.
2. We have leveraged AI tools to mine information and compile it.
