Energy Storage for Power System Planning and Operation

Zechun Hu

• Publisher: Wiley
• Year: 2020
• ISBN:
  9781119189114
• Edition: 1
• Topic: Technology & Engineering
• Subtopic: Renewable Power Resources
• Index: Technology & Engineering

An authoritative guide to large-scale energy storage technologies and applications for power system planning and operation

To reduce the dependence on fossil energy, renewable energy generation (represented by wind power and photovoltaic power generation) is a growing field worldwide. Energy Storage for Power System Planning and Operation offers an authoritative introduction to the rapidly evolving field of energy storage systems. Written by a noted expert on the topic, the book outlines a valuable framework for understanding the existing and most recent advances in technologies for integrating energy storage applications with power systems.

Filled with full-color illustrations, the book reviews the state-of-the-art of energy storage systems and includes illustrative system models and simulations. The author explores the various techniques that can be employed for energy storage that is compatible with renewable energy generation. Designed as a practical resource, the book examines in detail the aspects of system optimization, planning, and dispatch. This important book,

• Provides an introduction to the systematically different energy storage techniques with deployment potential in power systems
• Models various energy storage systems for mathematical formulation and simulations
• Contains a review of the techniques for integrating and operating energy storage with renewable energy generation
• Analyses how to optimize power systems with energy storage, at both the transmission and distribution system levels
• Shows how to optimize planning, siting, and sizing of energy storage for a range of purposes

Written for power system engineers and researchers, Energy Storage for Power System Planning and Operation introduces the application of large-scale energy storage for the optimal operation and planning of power systems.

1
Introduction

1.1 Evolution of Power System and Demand of Energy Storage

The normal operation of a power system constantly requires a balance of generation and demand. In traditional bulk power systems, the majority of power generation units are thermal (fossil fuel), hydro, and nuclear generators. Typically, the thermal or hydro generators are optimally dispatched to meet varying demands. Because of the huge demand for electricity to support the operation of modern society, thermal generators with a very large total installed capacity burn vast amounts of fossil resources each year. Over time, their greenhouse gas and other pollutant emissions lead to serious environmental problems.

To reduce the dependence on fossil energy, renewable energy generation (REG), represented by wind power and photovoltaic (PV) power generation, has been growing rapidly all over the world in recent years. According to data from Global Wind Energy Council (GWEC), the total installed capacity of wind worldwide was about 24 GW at the end of 2001, while this capacity reached 591 GW in 2018 [1], which increased by about 24 times. The global cumulative installed wind energy capacities from 2011 to 2018 are illustrated in Figure 1.1. In addition, as of the end of 2018, the total installed capacity of PV generation worldwide reached about 503 GW according to the statistics provided by the IEA Photovoltaic Power System Programme [2]. The total installed capacity of solar power generation was about 99.9 GW in 2018, which is comparable to all the installed capacity (about 100.9 GW) by 2012. In only 10 years, the world's total PV capacity increased by over 3600% – from 14.5 GW in 2008. The boom of PV capacity can be seen from Figure 1.2 [2, 3]. It is expected that the total installed capacity of PV will reach 1.0 TW by 2022.

With the large‐scale integration of renewable energy generation into power systems, the power generation mix is gradually changing, which leads to the changes of power flow among the power networks. Different from the traditional generation units, the power outputs of wind turbines and PV panels are constrained by weather conditions, which are difficult to forecast precisely. The random and fluctuating nature of wind and solar power brings new challenges to both planning and operation of power systems. It is more difficult to guarantee the balance between generation and demand in real‐time power system operation than before.

Figure 1.1 Global cumulative installed wind energy capacity.

Figure 1.2 Global cumulative installed PV capacity.

Figure 1.3 Impacts of wind power on power systems, displayed by time and spatial scales relevant for the studies [4].

According to different time‐scales and geographical ranges, reference [4] classifies the impacts of wind power integration into three aspects: power balance, power adequacy, and network adequacy (as illustrated in Figure 1.3). Actually, the impacts of large‐scale integration of PV generation are similar to that of wind power, except that PV panels cannot generate electricity during nighttime.

Reference [5] summarizes the four impacts of variable renewable generators from the aspect of power system flexibility. The first is the increased need for frequency regulation, because wind and solar power can increase the short‐term variability of the net load (load minus the power of REG). The second is the increase in the ramping rate, or the speed at which load‐following units must increase and decrease their output. The third impact is the uncertainty of the renewable resource. The final impact is the increase in overall ramping range and the associated reduction in minimum load, which can force baseload generators to reduce output. In summary, the increased variability and uncertainty of the net load requires a greater amount of flexibility and operating reserves in the power system.

In considering the operation of electricity markets with a high penetration of REG, three key characteristics of renewable technologies are identified in reference [6]:

1. Variability and uncertainty. The variability is partially predictable but also partially uncertain.
2. Low short‐run marginal costs (SRMC). Many renewable technologies have very low operating costs, or SRMC.
3. Nonsynchronous. Wind turbines and PV panels are nonsynchronously connected to the power grid. This means that they interact with the grid in a different manner when compared to synchronously connected generators. In the absence of sophisticated power control, they do not contribute to frequency stability, system inertia, and other grid‐related services in the same way as the synchronous generators.

Electricity markets that incorporate large quantities of variable renewable generation...