Grid-Scale Energy Storage Systems and Applications

Fu-Bao Wu,Bo Yang,Ji-Lei Ye

• Publisher: Academic Press
• Year: 2019
• ISBN:
  9780128152935
• Topic: Physical Sciences
• Subtopic: Energy

Grid-Scale Energy Storage Systems and Applications provides a timely introduction to state-of-the-art technologies and important demonstration projects in this rapidly developing field. Written with a view to real-world applications, the authors describe storage technologies and then cover operation and control, system integration and battery management, and other topics important in the design of these storage systems. The rapidly-developing area of electrochemical energy storage technology and its implementation in the power grid is covered in particular detail. Examples of Chinese pilot projects in new energy grids and micro grips are also included.

Drawing on significant Chinese results in this area, but also including data from abroad, this will be a valuable reference on the development of grid-scale energy storage for engineers and scientists in power and energy transmission and researchers in academia.

• Addresses not only the available energy storage technologies, but also topics significant for storage system designers, such as technology management, operation and control, system integration and economic assessment
• Draws on the wealth of Chinese research into energy storage and describes important Chinese energy storage demonstration projects
• Provides practical examples of the application of energy storage technologies that can be used by engineers as references when designing new systems

Chapter 1

Development of energy storage technology

Abstract

Chapter 1 introduces the definition of energy storage and the development process of energy storage at home and abroad. It also analyzes the demand for energy storage in consideration of likely problems in the future development of power systems. Energy storage technology's role in various parts of the power system is also summarized in this chapter. In addition, the prospects for application and challenges of energy storage technology in power systems are analyzed to offer reference methods for realizing sustainable development of power grids, solving the contradiction of imbalance between power supply and demand, and improving reliability of power supply.

Keywords

Challenge; Energy storage; Requirements; Role

1. 1.1 Basic concept
2. 1.2 The development history of energy storage technology
3. 1.3 Demands and functions of energy storage technology in power systems
   1. 1.3.1 Demand analysis of grid development in energy storage technology
      1. 1.3.1.1 Peak–valley gap intensifies demand for energy storage technology
      2. 1.3.1.2 Demand for energy storage technology due to the large-scale development of renewable energy
      3. 1.3.1.3 Demands of distributed power generation and smart grid construction on energy storage
   2. 1.3.2 Role of energy storage technology in power systems
      1. 1.3.2.1 Peak load shifting
      2. 1.3.2.2 Improving grids' accommodation to new energy
      3. 1.3.2.3 Spare power sources
      4. 1.3.2.4 Improving quality of electric energy
4. 1.4 Application outlook and challenges of energy storage technology in power systems
   1. 1.4.1 Application outlook
      1. 1.4.1.1 New energy power generation side
      2. 1.4.1.2 Urban power distribution network side
      3. 1.4.1.3 Distributed power supply and microgrid side
      4. 1.4.1.4 End user side
   2. 1.4.2 Challenges
      1. 1.4.2.1 Technical challenges
      2. 1.4.2.2 Challenges of policy and mechanisms
      3. 1.4.2.3 Economic challenges
5. Further reading

Power production is the basic pillar for the functioning of modern society and one of the main energy sources for the development of all industries. The three major elements for a power system are power generation facilities, power transmission and distribution, and power consumption equipment. Power generators convert mechanical energy into electrical energy that is transmitted and distributed to users via transformers, converters, and electric wires. At the user's end, electric energy is converted to mechanical energy, heat energy, and light energy by means of electric motors, electric ovens, and electric lamps. These power generators, transformers, converters, electric wires, and electric consumers for the production, conversion, transmission, distribution, and consumption of power are connected to form a whole that is called a power system.

With the continuous development of society and the economy, the operation of the power system is changing dramatically. Currently, China's power grid operation confronts the following problems and challenges:

• 1. Unreasonable electric power production structure. At the end of 2013, China's coal-fired power accounted for 69.13% of the country's total installed capacity, while the installed capacity of well-modulated hydropower accounted for 22.45%, a low proportion in the total. The power source structure with coal-fired power as the main source leads to the insufficient peak modulation capability of the power system.
• 2. Robust development of intermittent energy development. Intermittent energy is gradually increasing penetration in the power grid, which brings enormous challenges to grid peak modulation, safe and stable operation, and quality of electricity supply.
• 3. Users' demand for power varies greatly at different times and in different seasons and regions. With the gradual increase in the power consumption gap between the peak time and valley time, the peak modulation problem is more obvious, which often leads to the low voltage at peak load time and operation under low voltage. At the valley load time, power equipment has a shorter operation time and excess capacity.

To solve these problems, energy storage technology can penetrate each link of the power system and play different roles in generation, transmission, transformation, distribution, and consumption. As a flexible part of a smart grid, an energy storage system can effectively realize demand-side management, eliminate peak–valley gaps, improve the operational efficiency of electric equipment, reduce power supply costs, enhance the capability of connecting large-scale renewable energy into the power grid, remove the bottlenecks of energy structure adjustment, play a role as a spare power source, improve the quality of power, and meet different demands of the increasingly developing modern power system.

This chapter introduces the definition of energy storage and the development process of energy storage at home and abroad. It also analyzes the demand for energy storage in consideration of likely problems in the future development of power systems. Energy storage technology's role in various parts of the power system is also summarized in this chapter. In addition, the prospects for application and challenges of energy storage technology in power systems are analyzed to offer reference methods for realizing sustainable development of power grids, solving the contradiction of imbalance between power supply and demand, and improving reliability of power supply.

1.1. Basic concept

Generally speaking, energy storage refers to a range of technologies and measures that convert an energy form into another energy form via certain media or devices, and release energy in a special form when necessary.

In a narrow sense, the storage of electric energy refers to technologies and measures that store electric energy with chemical or physical means and release the energy when necessary. Energy storage in this book refers only to the storage of electrical energy.

Traditionally speaking, the production, transmission, distribution, and consumption of electric energy are simultaneous. In other words, the power produced by power generation plants at any moment must equal the sum of the power used by consumers and grid loss. The application of energy storage technology in power systems may change this mode and solve the problem of the time and space mismatch between electrical energy production and consumption to achieve the objectives of optimizing power resource distribution, improving the quality of electric power, promoting utilization of renewable energy, saving energy, and reducing emissions.

1.2. The development history of energy storage technology

Electric energy storage is not a new technology. As far back as 1786, Italian physicists discovered the existence of bioelectricity. In 1799, Italian scientist Alessandro Giuseppe Antonio Anastasio Volta invented modern batteries. In 1836, batteries were used in communication networks. In the 1880s, New York used lead–acid batteries for power supply to road lamps in its DC power supply system to shut down power generators at night.

With the development of power technology, pumped hydro storage power stations will be gradually used in grid peak modulation. The world's earliest pumped hydro storage power station was the Netala Power Station set up in 1882 in Zurich, Switzerland. It was a seasonal pumped hydro storage power station with a lift of 153 m and power of 515 kW. In 1908, Italy built a pumped hydro storage power station on the Ubyangni Mountain. In 1912, Italy set up Veroni Pumped Hydro Storage Power Station that utilized the 156 m–high fall between two natural lakes and had an installed capacity of 7600 kW. In the 1950s, more than 50 pumped hydro storage power stations were put into operation across the world. From the 1960s, pumped hydro storage power stations had entered a robust development period. The United States, Japan, and Western Europe became the pioneers in the large-scale development of pumped hydro storage power stations. After the 1990s, developed countries slowed the development of pumped hydro storage power stations, while developing countries, with China as a key representative, started the large-scale construction of pumped hydro storage power stations.

Pumped hydro storage (PHS), an energy storage technology most extensively applied in the power system, is mainly used to balance peak and valley loads, regulate frequency and phase, back up in case of emergencies, make a black start, and offer spare energy for the system. By the end of 2011, PHS power stations with installed capacity of above 123,400 MW were put into operation. By the end of 2012, China's PHS units of above 20 GW were in operation. According to statistics, the world's total installed capacity of PHS power stations was 1600 MW in 1950, 3500 MW in 1960, 16,000 MW in 1970, 46,000 MW in 1980, 79,000 MW in 1988, 98,273 MW in 1998, and 127,000 MW in 2010. The growth trend is illustrated in Fig. 1.1. The Bath County Pumped Storage Power Station in the United States has the largest scale with the installed capacity of 2100 MW. The Power Station of San Fiorano in Italy has the highest water head of 1417 m. Japan's Kannagawa PHS Power Station, boasting the highest unit capacity, has an installed capacity of 2820 MW, unit capacity of 470 MW, and the water head of 695 m. PHS power stations can be built according to discretionary capacity and classified into daily, weekly, and seasonal based on regulation periods. The major restricting factors for the wider application of PHS power stations are great difficulty in site selection, long construction period, and high investment.

Compressed air energy storage (CAES) refers to a gas turbine generation plant for peak load regulation. To achieve the same power output, a CAES plant's gas consumption is 40% lower than that of conventional gas turbine generators. Conventional gas turbine generators need to consume two-thirds of the input fuel for air compression when generating power, while a CAES plant can compress air in advance with cheap power from the valley load period of the grid, and then release the stored energy and some gas for power generation according to the actual demand. The compressed air is often stored in proper underground mines or caves under lava. To build such caves through lava takes 1.5–2 years.

Figure 1.1 Total installed capacity of global PHS power stations.

The first CAES plant was a 290-MW power generation unit built in Hundorf, Germany, in 1978. In 1991, the second commercial CAES plant of 110 MW was set up in McIntosh, Alabama. A total of 30 months and...