From homes to grids: Discover the world of energy storage applications

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2024/09/11 – Energy storage is indispensable for advancing the energy transition. Wind and solar power generate electricity irregularly depending on wind strength or sunlight. However, electricity must always be available—energy storage can help align supply with demand.

There are different segments within the market:

Residential Storage primarily utilizes lithium-ion batteries. Typical applications include storing excess solar energy from home photovoltaic systems to maximize self-consumption and providing backup power during outages. Storage capacities for residential use typically range from 5 to 15 kWh, with costs between 400 and 800 euros per kilowatt-hour (kWh) of installed capacity. This segment currently leads the market in Europe, accounting for 70% of the annual installed capacity.

Commercial Storage also relies heavily on lithium-ion batteries. Businesses frequently use these systems to reduce peak loads, lower energy costs, and increase the efficiency of their photovoltaic installations. The motivation for expanding storage in this segment mirrors that of residential storage: self-sufficiency, high and volatile energy prices, and the growing importance of flexibility and supply security. Costs typically range between 350 and 600 euros per kWh, depending on the project's size and specific requirements. In this segment, flow batteries are also common, particularly in larger systems and high-cycle applications. Unlike traditional batteries, flow batteries use a liquid electrolyte stored in external tanks, allowing for flexible scaling of power and capacity. Costs range from 500 to 1,000 euros per kWh, depending heavily on the technology and specific use case. Commercial storage systems hold a market share of around 9%. A typical industry example: The 50 MW agricultural and photovoltaic integration project by CNNC in Tengzhou, China. Officially launched on December 30, 2020, the project has an installed capacity of 5 MW/10 MWh and offers numerous functions, including peak load shifting and maintaining grid security during low sunlight conditions.

Utility-Scale Storage is typically used by energy providers to maintain grid stability. Lithium-ion batteries are also the preferred choice for these applications. Due to economies of scale in large installations, costs per kWh are lower than in smaller systems, ranging from 250 to 700 euros per kWh. Flow batteries are also used in utility-scale storage, with costs comparable to those of lithium-ion batteries for large projects, typically ranging from 400 to 800 euros per kWh. Utility-scale storage systems account for about 21% of the energy storage market in Europe.

Portable Storage offers a flexible, mobile solution for temporary energy needs. These systems, which also primarily use lithium-ion batteries, are frequently used in applications such as construction sites, events, or emergency power backup during temporary outages. With typical capacities ranging from 1 to 5 kWh, they are smaller than stationary residential storage systems but are easy to transport and versatile. Prices for portable storage vary widely depending on capacity and features. Portable storage is gaining a growing share of the energy storage market, particularly in areas where temporary energy is needed, and they are increasingly important as backup solutions for households and businesses.

In the utility-scale segment, SVOLT is predominantly active in its home market in China: For the grid-connected 400,000-kW photovoltaic and energy storage project by Guandong Hydropower Group in the Awat district, the company supplied a total of 80 prefabricated battery containers with individual capacities of 5.0176 MWh each and a total capacity of 401.408 MWh. Each container stores enough energy to fully charge ten electric vehicles.

The entire energy storage system supports applications such as the integration of solar power plants, primary frequency regulation, secondary frequency regulation, or reactive power support. Additionally, the energy storage system can manage grid dispatching and participate in grid auxiliary services.