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Hitachi's Energy Storage System for a Cleaner Future Hitachi's Energy Storage System for a Cleaner Future

  • Energy

Maintaining a stable supply of high-quality electricity is becoming a greater challenge as larger amounts of renewable energy are introduced to the power grid. High-quality electricity that is stable in voltage and frequency is essential as a power source. The demand for energy storage systems to overcome this challenge is greatly increasing.

Energy Storage System to Balance Supply and Demand of Electricity

Large-capacity, lithium-ion batteries can meet a variety of needs in large electrical equipment and new power systems.

Distribution of electricity requires a continuous balancing act in adjusting supply to meet demand. If this balance becomes unstable, it causes fluctuations in frequency, and this could lead to power outages. Output of electricity from renewable energy sources such as solar and wind power generation depends on changing weather conditions and wind velocity and therefore fluctuates readily. To incorporate larger amounts of renewable energy into the grid, we need to effectively address this issue. Thus, energy storage systems with frequency regulation capabilities, along with control systems using information technology, have been gaining attention as promising solutions to maintain a stable power supply.

Hitachi's activities in this field extend from research and development to system integration, in addition to manufacturing materials for energy storage devices and batteries for consumer, industrial, and automotive applications. Hitachi deals with a wide range of systems and can configure economical solutions for specific applications by optimizing the best energy storage system for a given application. These include advanced lead-acid batteries, which can store relatively large amounts of energy, and lithium-ion batteries, which can deliver a high level of output over a short period.

Developing the 1-MW Container-Type Energy Storage System as an Optimal Solution for Frequency Regulation in Ancillary services

The United States, one of the leaders in the large-scale deployment of renewable energy, has already deregulated its electricity market, and its power grid has become open for trade. The retail electricity market is now fully deregulated in many areas. PJM (Pennsylvania, New Jersey, Maryland Interconnection), which operates transmission systems in the northeast region of the United States as the country's largest Regional Transmission Organization (RTO), has already opened the electricity market for frequency regulation.
Hitachi recognized the opportunities in this market and launched a project to develop and provide energy storage solutions in 2013.

The 1-MW container-type energy storage system, "CrystEna," is the fruit of teamwork in the Hitachi group.

First, Hitachi started working on the development of a container-type lithium-ion battery energy storage system as an optimal solution for frequency regulation. In the development process, Hitachi determined that reliability and having a service life of around 10 years would be critical for the system to give customers confidence to invest. Hitachi Research Laboratory developed a simulator to evaluate battery life precisely, as it would be impractical to test battery life by charging and discharging batteries over 10 years. Hitachi's Omika Works worked on improving the control system and power conditioning system, which are critical parts of the energy storage system.
Hitachi Chemical Company, Ltd. and its group company, Shin-Kobe Electric Machinery Co., Ltd. worked on improving the energy storage cells. As a result of the combined strengths and efforts of these Hitachi group companies, the 1-MW container-type energy storage system was launched as a single, integrated unit optimized for frequency regulation.

Hitachi group continues to work on extending battery life and making the system smaller. Hitachi plans to market the energy storage system in the U.S. as a significant contribution in the frequency regulation market.

Note: CrystEna is a registered trademark for the brand name representing overall energy storage system solutions made by Hitachi group. The name was created combining "Crystal" of state-of-the-art technologies in the Hitachi group and "Energy."

Large capacity and long life. Lithium-ion batteries are expected to have a system life of around 10 years.

Inside the container. 1-MW power conditioning system (PCS), 450 kWh batteries and control systems.

Hitachi's Energy Storage Solutions, Contributing to a Stable Power Supply

Hitachi is not only looking to the U.S., where frequency regulation markets already exist, but also sees great market potential in the energy storage field worldwide. For example, there is already growing demand for stabilization of the electrical grid in Japan as the amount of renewable energy grows. Small-scale power grids and microgrids on islands will need energy storage solutions for balancing demand and supply as well as for utilization during peak times. Hitachi contributes to stable energy supplies, which are essential to comfortable living for people around the world, and will continue its efforts through a variety of innovative solutions, including the container-type energy storage system.