energiasalvestus

Energiasalvestus is the practice and set of technologies used to store energy for later use, enabling balance between energy supply and demand, grid reliability, and greater deployment of variable renewable energy sources. In Estonian, energiasalvestus refers to energy storage in general, while specific implementations may be described as storage technologies or systems.

Storage technologies can be grouped into several broad categories. Mechanical storage includes pumped-hydro storage, which uses gravitational potential energy in water, and compressed air energy storage, which stores energy as compressed air in underground caverns. Electrochemical storage covers batteries, such as lithium-ion and flow batteries, as well as emerging solid-state chemistries. Thermal storage uses materials that retain heat or cold, for example molten salt in solar-thermal plants or phase-change materials for building or industrial cooling. Chemical storage relies on converting electricity to chemical fuels, notably hydrogen produced by electrolysis, with energy later recovered through electrochemical or fuel-cell processes. Other concepts include gravity-based and hybrid systems that combine multiple approaches.

Typical applications are grid stabilization, peak shaving, renewable-energy integration, backup power, and off-grid or microgrid operation. Key performance measures include energy capacity (megawatt-hours), power rating (megawatts), round-trip efficiency, response time, and project lifetime. Costs and economics, including levelized cost of storage, are influenced by technology maturity, location, and regulatory frameworks.

Energiasalvestus plays a central role in transitioning to low-carbon energy by mitigating intermittency, reducing curtailment of renewables, and enabling more flexible and resilient electricity systems. Environmental, safety, and material considerations—such as land use, mining impacts, recycling, and safety protocols—affect technology choices and policy development.