Thermal Energy Storage (TES)

TES systems store energy in the form of heat or cold and are an efficient way to manage energy demands, particularly in large buildings and industries. This storage process typically involves water or advanced materials such as molten salts or phase-change materials. By charging during off-peak times and releasing stored energy during peak demand, TES helps reduce the strain on electricity grids and cuts costs for consumers.

Key Advantages of TES:

• Increased renewable energy utilization: TES systems can increase the use of renewable energy sources by up to 50%​(IRENA)​(Frontiers)
• Seasonal energy storage: TES systems can store energy for extended periods, including seasonal shifts, making them effective for long-term energy management​(IRENA)
• Scalability: The global TES market is expected to triple in size by 2030, with applications in buildings, industrial plants, and renewable energy facilities​(IRENA).

Notable TES Installations:

• Crescent Dunes Solar Energy Plant (USA): This concentrated solar power (CSP) plant uses molten salt to store thermal energy, providing power to over 75,000 homes. Its molten salt storage system allows for energy storage even when the sun isn't shining, ensuring a constant supply of electricity(IRENA)​​
• The Drake Landing Solar Community (Canada):This community uses solar thermal collectors to store heat in the ground during summer, which is then used to heat homes during winter, demonstrating the effectiveness of TES in seasonal energy storage​(Frontiers). .
• Hafod y Llan Farm (UK): Located in Snowdonia, this farm employs TES to store energy from solar panels and release it for heating and hot water, reducing reliance on fossil fuels and demonstrating TES's potential in agriculture​(IRENA)​(Frontiers). .

Mechanical Energy Storage (MES)

MES systems store mechanical energy, such as pumped hydropower storage, which stores energy by pumping water to elevated reservoirs during times of excess energy production. When demand rises, the water is released to generate electricity through turbines.

Key Advantages of MES:

• High energy capacity: MES systems, particularly pumped hydropower, can store vast amounts of energy and release it over extended periods​(Frontiers).
• Long lifecycle: These systems are known for their durability and can operate for decades with minimal efficiency loss​(Frontiers).
• Efficient large-scale energy management: MES systems can absorb energy from large renewable plants and help stabilize electrical grids during peak times.

Notable MES Installations:

• Bath County Pumped Storage Station (USA): As the largest pumped storage facility in the world, it can store up to 3,003 MW of energy, helping to manage peak loads for Virginia and surrounding areas​(IRENA).
• Dinorwig Power Station (UK): This pumped storage facility in Wales, known as the "Electric Mountain," provides up to 1,728 MW of stored energy for the UK's National Grid. It plays a crucial role in balancing the UK's energy supply and demand​(IRENA).
• Hongrin-Leman Pumped Storage Plant (Switzerland): A key facility in Europe's energy infrastructure, it stores renewable energy and supports the grid during periods of high demand​(IRENA).

TES and MES as Enablers of Renewable Energy Growth

Both TES and MES systems are critical enablers of the renewable energy revolution. These technologies bridge the gap between intermittent energy generation and continuous energy demand, enhancing grid reliability and reducing the need for fossil fuel-based backup power.

TES, for example, is widely used in district heating and cooling systems and can be applied to buildings, industries, and renewable energy plants. Combined with renewable sources such as solar thermal and wind energy, TES systems can decouple energy production from demand, storing energy during periods of excess generation and releasing it when needed​(IRENA)​(Frontiers). Similarly, MES, particularly through pumped hydropower, offers a reliable way to store large amounts of energy and regulate grid stability.

Future Outlook

With global targets for carbon neutrality by 2050, the role of energy storage systems like TES and MES will only grow in importance. Investment in TES systems is expected to reach between $13 billion and $28 billion by 2030​(IRENA), driven by a combination of government incentives, technological advances, and increasing demand for cleaner energy solutions.

As the world transitions towards more sustainable energy sources, TES and MES are proving essential for ensuring that renewable energy is not only generated but efficiently stored and utilized, supporting a greener and more resilient energy future.