Pumped Hydro Storage Can Provide Balancing And Grid Services

Pumped Hydro Storage

 

Power generated by renewables is often intermittent, and storing that energy for later use is a key step in embedding it in a reliable national electricity supply. Pumped hydro is one of the oldest, and cheapest, ways of doing this.

The technology has been around for over a century and is the most developed form of energy storage, with 90 GW in operation worldwide.

The global pumped hydro storage market size is estimated to be valued at US$ 330.00 Billion in 2021 and is expected to exhibit a CAGR of 7.18% between 2022 and 2030.

Off-river pumped hydro involves pairs of reservoirs, situated in hilly terrain and joined by a pipe with a pump and turbine. Energy is stored in the lower reservoir and then pumped back up to the upper reservoir when electricity is needed. The water then flows through a turbine to generate power, and the energy is released as a flow of water downstream.

Pumped hydro can be used to provide many valuable services, including spinning reserve, peaking generation, energy management and frequency control. In some countries, it can even be used to help manage emissions. It is not surprising that the electricity industry is seeking new ways to leverage this valuable technology, particularly as renewable energy capacity rises and the need for flexible backup grows.

However, while construction of new pumped hydro plants has declined for a number of reasons, such as competition from solar and wind, there are some innovative approaches that could reverse this trend. These new ideas combine the advantages of pumped hydro with novel energy storage technologies that may reduce costs and environmental impacts, while increasing efficiency and value.

One of the biggest challenges for pumped hydro storage is that it has a relatively low energy density. As the energy stored in the system is contained in the difference between the heights of the two reservoirs. To overcome this challenge, a pumped hydro power station requires a large reservoir with a steep slope. Ideally, the two reservoirs are located close together, whereas high above each other. This can be achieved with a natural slope in hilly terrain, or by building a dam with a steep slope and using a series of tunnels to raise the reservoir level.

The global cryogenic tanks market size is estimated to be valued at US$ 6.51 Billion in 2022 and is expected to exhibit a CAGR of 5.0% between 2023 and 2030.

While this type of storage has many benefits, it also has a number of environmental and economic costs. These include the need for a large area of land, which can be difficult to find in rural areas; and the long lead times and capital investment required for the technology. Other costs include the requirement to regularly inspect and repair pumping equipment.

The Greenko Group declared an investment of USD 1.2 billion for setting up a pumped storage project in Madhya Pradesh, India, in January 2023. The project will be connected to the interstate transmission system network and have a daily storage capacity of 11 GWh.