Low-Temperature Energy Systems with Applications of Renewable Energy

Andriy Redko, Oleksandr Redko, Ronald DiPippo

• Publisher: Academic Press
• Year: 2019
• Print ISBN:
  9780128162491
• eBook ISBN:
  9780128166024
• Topic: Technology & Engineering
• Subtopic: Energy
• Index: Technology & Engineering

Low-Temperature Energy Systems with Applications of Renewable Energy investigates a wide variety of low-temperature energy applications in residential, commercial, institutional, and industrial areas. It addresses the basic principles that form the groundwork for more efficient energy conversion processes and includes detailed practical methods for carrying out these critical processes. This work considers new directions in the engineering use of technical thermodynamics and energy, including more in-depth studies of the use of renewable sources, and includes worked numerical examples, review questions, and practice problems to allow readers to test their own comprehension of the material. With detailed explanations, methods, models, and algorithms, Low-Temperature Energy Systems with Applications of Renewable Energy is a valuable reference for engineers and scientists in the field of renewable energy, as well as energy researchers and academics. - Features end-of chapter review sections with questions and exercises for practical study and utilization. - Presents methods for a great variety of energy applications to improve their energy operations. - Applies real-world data to demonstrate the impact of low-temperature energy systems on renewable energy use today.

1

Principles and operation of refrigeration and heat pump systems

Abstract

A snapshot of world energy usage is shown with a focus on renewable sources. A brief summary is given of pertinent energy policies around the world. The processes needed to create and assess energy efficient systems are described. The history of heat pumps and refrigeration is presented along with qualitative descriptions of these machines. Quantitative analysis is carried out for ideal machines that set the standard for real-world systems. Practical heat pump and refrigeration systems are described in technical detail and analyzed using the principles of thermodynamics. Both vapor-compression and absorption refrigeration systems are discussed. The working fluid selection process is described with special emphasis on environmental impacts and international protocols. The chapter concludes with a discussion of modes of operation of heat pumps and cold storage systems.

Keywords

Energy consumption; Energy policy; Sustainability; Heat pumps; Refrigerators; Coefficient of performance; Efficiency; Vapor-compression; Absorption refrigeration; Cold storage

1.1. Trends in usage of low-temperature technologies

Modern generation of electricity and world energy consumption as of 2016 is provided mainly by fossil energy resources [1]. In many countries of the world there is a diversified use of energy resources. Long-term energy security, meaning “the uninterrupted availability of energy resources at an affordable price” [2], requires the timely supply of energy resources to meet the requirements of the economy and population, taking into account the challenges of sustainable development.

In countries around the world, the substitution of organic fuels is developing in different directions. In European countries, heat pump technology and organic Rankine cycle (ORC) technologies in combination with renewable energy sources (RES) are widely used. Solar energy is developing in Asia (China, Japan), Africa and Australia. Using solar and wind energy, Saudi Arabia plans to become an exporter of electricity. It is predicted that by 2050 global investments in RES will have prevailed in the use of wind (34%), hydro (30%) and solar (18%) energy [3]. Figures 1.1 and 1.2 show statistical data on the state and prospects of the development of global electricity, including RES [4].

The United States (US) plans to generate electricity from three sources: natural gas, solar energy and wind energy. The share of RES in the US of installed capacity was 8.5% in 2017 and is 12% in 2019 [5]. The Parliament of the European Union (EU) adopted a resolution in 2016 on a strategy of heating and cooling, according to which the technologies of direct combustion of fuel for heating purposes are admitted to be technically unpromising. In 2010 Germany, which imports about 71% of its hydrocarbons, adopted a state program aimed at increasing the share of renewable energy by 2050 from 10 to 60%. In Germany in 2015, the share of power generation by RES was 30% [6].

Trends in the development of world power engineering show that the generation of energy using RES will be decisive in the next two decades. At the same...

Table of contents

• Cover image
• Title page
• Table of Contents
• Copyright
• Dedication
• About the authors
• Preface
• Acknowledgments
• 1. Principles and operation of refrigeration and heat pump systems
• 2. Characteristics of low-temperature energy sources for heat pumps
• 3. Effective use of heat pumps for various heating applications
• 4. Heat pumps in the drying industry
• 5. Heating with geothermal systems
• 6. Geothermal energy in combined heat and power systems
• 7. Biofuels conversion: energy-saving processes and use of biogas
• 8. Hybrid systems with renewable energy sources
• 9. Industrial waste heat resources
• Index