Energy storage enables us to more seamlessly incorporate wind and solar generation into the grid by smoothing their fluctuating output, and helping improve power quality by matching supply with demand moment by moment.
Storage energy solutions can be implemented on a large scale to assist grid stability and provide new services like static reserve, or smaller-scale solutions in homes using behind-the-meter solutions. Technologies include pumped hydro (lifting water), batteries, thermal energy storage units and flywheels – each offering different methods of storing energy.
Lithium-ion battery storage
Lithium-ion batteries have become ubiquitous across a variety of consumer devices such as mobile phones, laptop computers and electric cars, due to their high energy density and highly efficient design – powering all three simultaneously without producing much waste heat.
Lithium-ion battery fires pose significant danger in facilities that produce or stock them; warehouses that stock them; and buildings where they’re installed. They’re notoriously difficult for fire crews to put out and can cause extensive damage to structures and the surrounding environment.
To reduce these risks, companies must implement standard operating procedures designed to ensure safe handling and storage practices are adhered to. Employees should have designated storage areas or purpose-built lithium-ion battery cabinets available as these solutions help minimise overheating risks as well as charging on unsafe surfaces. Staff members should also receive training on these procedures so they know what steps should be taken if a fire breaks out.
Sodium-sulfur battery storage
The sodium-sulfur battery is an intriguing storage technology with great potential. Its chemical reaction allows it to store and release electrical energy at a slow rate, making it an integral component of modern power grids. Unfortunately, however, its deployment faces numerous obstacles: including high costs, safety hazards, and environmental concerns.
Researchers are developing an advanced version of the sodium-sulfur battery that will operate efficiently at room temperature, making it simpler for large amounts of renewable energy to be stored safely.
The key to this new battery lies in its use of carbon-based cathode material that prevents polysulfides from forming, providing long-term cycling stability. Furthermore, an electrolyte made of indium triiodide speeds up conversion of sulfur into sodium sulfide for improved performance and discharge capacity – yielding an energy and power density comparable to lithium-ion batteries.
Thermal storage
Energy can be stored using various technologies. One popular approach is battery storage, which uses electricity to alter chemical bonds in materials before discharging its stored energy later. Other technologies include solar thermal storage and compressed air energy storage.
Energy storage enhances grid efficiency by alleviating transmission congestion and increasing grid flexibility. Furthermore, energy storage helps limit costly energy imports while improving energy security – including shifting renewable generation to evening peak demand.
Thermal energy storage systems can be utilized both on a large-scale to feed the grid or as small-scale residential behind-the-meter solutions. Thermal energy storage solutions can store both latent and sensible heat energy – the former can be stored using technical phase change materials while sensible heat can be stored in tanks and buildings.
Sand battery
The Sand Battery is a thermal storage system made up of sustainably-sourced sand or other granular materials such as industrial byproducts as its storage medium. It serves as a high-power and high-capacity reservoir for excess renewable energy generation, helps balance frequency in the grid, and produces heat without combustion.
Electrical resistance heating heats the sand to over 1,100 degrees Celsius (2192 degrees Fahrenheit). Hot particles of sand are then transferred into air using an innovative pressurized fluidized-bed heat exchanger designed by our team – similar to how an air-Brayton combined cycle power plant works – in order to produce electricity.
Vatajankoski Energy Utility in Finland has installed the world’s first commercial Sand Battery system in Kankaanpaa for heating residents’ homes, industry and community swimming pool needs. Capable of storing up to 100MWh, this facility aims to scale-up globally as it may replace fossil fuels used for processes above 100 degrees Celsius.