Energy storage

Also known as a “water battery”, PHS accounts for over 94% of installed global electrical energy storage capacity. It involves using excess energy to pump water to a higher elevation during low demand periods and releasing it to generate electricity during high demand. This technology supports large-scale energy storage as well as auxiliary services to the grid enhancing grid stability.

BESS are innovative solutions designed to store electrical energy generated by renewable sources, such as solar and wind power, for use when needed usually to mitigate intermittency. These systems play a central role in enhancing grid stability, reducing energy costs, and improving energy efficiency.

Applications of BESS include load shifting, where excess energy is stored during low-demand periods and released during peak demand; frequency regulation, which helps maintain a stable grid frequency; and backup power supply, providing reliable energy during outages.

Additionally, BESS can support microgrids, enabling isolated communities or facilities to operate independently from the main grid, and facilitate the integration of renewable energy sources, making the energy system more sustainable and resilient.

Supercapacitors, also known as ultracapacitors, are advanced energy storage devices that offer high power density and rapid charge-discharge cycles. Unlike traditional batteries, supercapacitors store energy through electrostatic separation of charges rather than chemical reactions. This allows them to deliver quick bursts of energy, making them ideal for applications requiring short-term power boosts and fast response times.

Supercapacitors are composed of two electrodes separated by an electrolyte. When voltage is applied, ions in the electrolyte move to the electrodes, creating an electric field that stores energy. This mechanism enables supercapacitors to charge and discharge rapidly, with minimal degradation over time. They are used in various applications, including backup power supplies, regenerative braking systems in electric vehicles, and grid stabilisation.

Molten Salt Heat Storage technology is a reliable and dispatchable solar technology often used in Concentrated Solar Power (CSP) systems. It captures sunlight as thermal energy and stores it in molten salts or heat transfer fluids within large, durable tanks. These salts act as a reusable and recyclable "fuel," providing thermal energy for electricity generation even when the sun isn't shining.

With a lifespan of 30–40 years, this sustainable storage solution supports round-the-clock solar power availability, reducing fossil fuel reliance and enhancing grid stability.

Heat Storage technology within district heating systems plays a major role for enhancing energy efficiency and sustainability. AFRY specialises in large-scale thermal storage solutions, such as thermal heat caverns, which enable higher efficiency and lower costs per unit of energy stored. These systems integrate effectively into district heating and industrial processes, providing optimal plant size, network design, and consumer connections.

AFRY also offers comprehensive services for the procurement, implementation, and rehabilitation of district heating systems, ensuring efficient and environmentally sound heating solutions.

Compressed Air Energy Storage (CAES) is a key technology in AFRY's portfolio of energy storage solutions. CAES works by compressing air and storing it in underground caverns or above-ground tanks. When energy is needed, the compressed air is released, heated, and expanded through turbines to generate electricity. This technology is essential for balancing the intermittent nature of renewable energy sources like wind and solar, capturing excess energy during periods of high production and releasing it during peak demand.

AFRY's expertise in CAES includes feasibility studies, development support, basic design, authorisation and permitting, environmental studies, grid studies and power system integration, project development and management, technical specifications, financing support, lender’s technical advisory, owners’ engineering services including design review, site supervision and commissioning, asset management, maintenance support, and HSE plans.

Hydrogen storage converts electricity into hydrogen for long-term storage, suitable for sectors like heavy industry and transport. Accelerating the move to low carbon and renewable hydrogen will require coordination and collaboration across developers, power and gas networks, industry, policy makers and investors. This is not without its challenges and significant effort will be required to overcome the technical and economic barriers.

Hydrogen storage is a pivotal technology in AFRY's approach to sustainable energy solutions. By integrating renewable energy sources such as wind, solar, and hydro with advanced electrolysis processes, AFRY supports the production of hydrogen that can be utilised across various sectors. This includes applications in medical oxygen, green steel production, sustainable aviation fuel, fuel cell vehicles, and large-scale energy storage. Our expertise in hydrogen storage encompasses the use of compressed gas, liquefied hydrogen, and chemical storage methods, ensuring maximum efficiency and safety.

AFRY is supporting our clients to advancing hydrogen and power-to-x technologies to create a resilient and climate-neutral energy system.