Gravity Energy Storage

Asmae Berrada,Khalid Loudiyi

• Publisher: Elsevier
• Year: 2019
• ISBN:
  9780128172926
• Topic: Scienze fisiche
• Subtopic: Energia

Gravity Energy Storage provides a comprehensive analysis of a novel energy storage system that is based on the working principle of well-established, pumped hydro energy storage, but that also recognizes the differences and benefits of the new gravity system. This book provides coverage of the development, feasibility, design, performance, operation, and economics associated with the implementation of such storage technology. In addition, a number of modeling approaches are proposed as a solution to various difficulties, such as proper sizing, application, value and optimal design of the system.

The book includes both technical and economic aspects to guide the realization of this storage system in the right direction. Finally, political considerations and barriers are addressed to complement this work.

• Discusses the feasibility of gravity energy storage technology
• Analyzes the storage system by modelling various system components
• Uniquely discusses the characteristics of this technology, giving consideration to its use as an attractive solution to the integration of large-scale, intermittent renewable energy

Chapter 1

Energy Storage

Abstract

With the increasing use of renewable energy (RE) technologies, more emphasize is put on energy storage (ES). This is very important in the transition from fossil fuels to renewable sources and is directly related to reducing GHG emissions. To ensure a smooth functioning of the electric grid, a balance has to be established between energy production and demand. Fluctuations between energy demand and supply can be harmful to the electric grid and to the overall consumer satisfaction. Therefore, flexible generation in combination with ES tends to be the optimal solution to ensure grid stability. ES is highly required to overcome the intermittent nature of RE sources. A number of ES technologies have been developed to store the excess energy, by converting electric energy to chemical, thermal, electrochemical, mechanical, or gravitational energy. Various types of ES systems are discussed in this chapter. ES domain requires more exploration. It is vital to understand the most recent innovative ES systems that are currently under research and development. Novel alternative designs of pumped hydrostorage have been also described.

Keywords

Alternative PHES; Energy storage; ES comparision; Novel design; Status worldwide

Introduction

The development of the industrial sector throughout the years has led to a clear enhancement in living conditions. Accordingly, an increase in energy consumption has been witnessed [1]. As for now, many countries are focusing on developing the field of renewable energy (RE) and enhancing its control strategies and management [2]. Electricity generated from RE technologies is predicted to increase from only 10% in 2010 to 35% in 2050 [3]. The variability of energy produced by renewable sources represents one of the main challenges faced by the electric grid. As a matter of fact, one of the solutions to this issue is energy storage (ES). This solution has been proved to be an effective one for ensuring the integration of RE into the grid [4]. ES technologies have technical and economic advantages from the generation of energy to its supply [5]. Storage also balances demand and supply to avoid energy losses or power cuts. Hence, ES technologies compensate for any lags between generation and supply especially for RE generation and enhance the reliability of the utility grid [5].

ES systems are crucial in meeting power demand and in incorporating more environmentally friendly energy technologies. There are several benefits of using ES such as reducing energy costs, improving indoor air quality when using benign energy for heating or cooling, reducing energy consumption, increasing the operating flexibility, and last but not least, reducing operating and maintenance costs. Moreover, further advantages to the use of ES have been reported, which include reducing equipment size, increasing the operating efficiency and utilization of equipment, conserving and substituting fossil fuels by reducing their use, as well as decreasing GHG emissions.

ES systems have a great potential in increasing the efficiency and effectiveness of energy production systems by contributing to the substitution of fossil fuels. However, ES is difficult to understand and cannot be investigated without fully considering the whole electric value chain. To get the maximum benefit of a storage system, specific set of actions must be performed in the different energy sectors. Performance criteria of ES help in evaluating the performance and usefulness of the system to determine the possibility of developing more advanced systems. Evaluating ES systems should compromise the performance of a study about the potential impact of this system at different levels.

Nowadays, reliable supply of energy is a crucial aspect regarding how civilizations become more and more industrialized. For raw energy to be useful, it should be converted to what is called energy currencies. This is commonly done through heat release. As an example, industrial processes make use of steam for heating purposes. This later is created by transferring heat from burning fuel to water. Electricity is generated mainly with steam-driven turbogenerators; this steam is usually created using fossil fuels or nuclear energy as the source of heat. Demand on power in all of its forms is usually not steady, nor is the supply. For example, solar energy is not steady either for thermal or electric energy. In the past, the only solution to cope with the variability of supply and demand and to ensure the reliability of power supply was to convert large quantities of power to meet peak demand periods. This approach results in lower efficiencies and higher capital investments due to the fact that generating systems should be operating less than their full capacity most of the time.

Load management is a very important aspect because it helps in smoothing power demand and thus can sometimes leads to reducing capital in...