Introduction to Energy Systems E-Book

Ibrahim Dincer

• Herausgeber: John Wiley & Sons
• Kategorie: Fachliteratur
• Sprache: Englisch

Seitenzahl: 842

Veröffentlichungsjahr: 2023

Beschreibung

Introduction to Energy Systems An in-depth introduction to applications and analysis of energy systems, covering both renewable and traditional types of energy systems In Introduction to Energy Systems, the content is uniquely designed to cover comprehensive descriptions and assessments of all the key types of energy sources, including fossil fuels-based, nuclear, and renewable energy systems, with a special focus on their design, analysis and assessment, technical and operational aspects, and applications. As a comprehensive resource, the work also introduces many topics not typically covered in other energy system textbooks, such as system design and assessment through exergy, environmental impact assessment of energy systems, and life cycle assessment. From a theory standpoint, the book provides context on the importance of energy and the issues related to energy we face in our world today, with close attention paid to key environmental and sustainability issues. Furthermore, the book includes illustrative examples and problems, and case studies. To aid in seamless reader comprehension, helpful questions and problems are included at the end of each chapter. Sample topics covered in Introduction to Energy Systems include: * Fundamental concepts and thermodynamic principles, traditional and innovative systems, and detailed applications in renewable energy systems, including solar, wind, geothermal, biomass, hydro, and marine energies * Different types of fuels used in energy systems today, discussions of their combustion characteristics with a clear analysis of each one, and analyses and assessments through energy and exergy approaches * Industrial ecology and life cycle assessment, with the intention of clearly assessing the environmental impacts of energy systems * How to write balance equations for mass, energy, entropy and exergy, calculate the required capacities, and find the energy and exergy efficiencies and/or energetic and exegetics coefficient of performance values Introduction to Energy Systems serves as a valuable learning resource for both undergraduate and graduate students studying courses, such as Introduction to Energy Systems, Energy System Design, Renewable Energy, Energy & Sustainability, and Fundamentals of Renewable Energy.

Leseprobe

Introduction to Energy Systems

Ibrahim Dincer and Dogan Erdemir

Ontario Tech. University, ON, Canada

Copyright © 2023 by John Wiley & Sons, Inc. All rights reserved.

Published by John Wiley & Sons, Inc., Hoboken, New Jersey.

Published simultaneously in Canada.

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Library of Congress Cataloging-in-Publication Data

Names: Dincer, İbrahim, 1964- author. | Erdemir, Dogan, author.

Title: Introduction to energy systems / Ibrahim Dincer, University of Ontario ON, CA, Dogan Erdemir, University of Ontario Institute of Technology, ON, CA.

Description: Hoboken, New Jersey : John Wiley & Sons Inc., [2023] | Includes bibliographical references and index. | Summary: “Energy is critical commodity for every society, and nothing is technically possible without energy. Energy studies are carried out by every discipline, and many academic programs cover energy related courses. During the past decade it has been clear that developing an introductory level undergraduate textbook is badly needed. That has been a kind of motivation to prepare a book about conventional and innovative energy systems and applications and their linkages to the environment and sustainable development with numerous analysis methods, including energy and exergy approaches, illustrative examples and cases studies to provide a solid knowledge source for undergraduate students in engineering programs, potentially ranging from mechanical to chemical and electrical to industrial engineering programs”-- Provided by publisher.

Identifiers: LCCN 2023009320 (print) | LCCN 2023009321 (ebook) | ISBN 9781119825760 (hardback) | ISBN 9781119825777 (epdf) | ISBN 9781119825784 (epub)

Subjects: LCSH: Power resources.

Classification: LCC TJ163.2 .D556 2023 (print) | LCC TJ163.2 (ebook) | DDC 621.042--dc23/eng/20230323

LC record available at https://lccn.loc.gov/2023009320

LC ebook record available at https://lccn.loc.gov/2023009321

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Cover Design: Wiley

Set in 9.5/12.5pt STIXTwoText by Integra Software Services Pvt. Ltd., Pondicherry, India

Preface

Energy is considered a critical commodity for every society, and we know that nothing is technically possible without energy. Energy studies are carried out by every discipline, and many academic programs cover energy-related courses. During the past decade it has been clear that developing an introductory level undergraduate textbook is badly needed, which has been a kind of motivation to prepare such a book about conventional and innovative energy systems and applications and their linkages to the environment and sustainable development with numerous analysis methods, including energy and exergy approaches, illustrative examples, and cases studies to provide a solid knowledge source for undergraduate students in engineering programs, potentially ranging from mechanical to chemical and electrical to industrial engineering programs. Furthermore, theory and concepts along with analysis and assessment are emphasized throughout this comprehensive book, reflecting new techniques, models and applications, together with complementary materials and recent information.

This book starts with some introductory perspectives on energy and the environment. Importance of energy, energy-related issues and environmental problems are discussed with some important solutions. The role of engineering in energy and environment-related problems is also provided. The concepts of life cycle assessment and industrial ecology are presented with illustrative examples. Finally, the need for energy labeling is discussed. Second chapter deals with energy sources and sustainability. First, the key instruments, drivers and indicators are introduced. Then, the historical perspectives of the energy consumption and generation are presented with developments and landmark type achievements. Next, regression analysis and future projection techniques for energy systems are introduced. Finally, dimension of sustainability and sustainable development indexes are discussed with illustrative examples. In Chapter 3, the thermodynamic analyses of energy systems are introduced in detail with illustrative examples. Thermodynamic balance equations, which are mass, energy, entropy, and exergy balance equations, are written for common components that are commonly used in energy systems. Some illustrative examples are in this regard presented. Chapter 4 provides the background for combustion processes. Fossil fuels and their impacts are discussed. Then, combustion of fuels is introduced. Thermodynamic analysis for combustion in a closed system and an open system are analyzed with illustrative examples. As a following topic, nuclear energy systems are provided in Chapter 5. First, historical perspectives and types of nuclear energy are introduced. Nuclear fission and nuclear fusion processes are presented. Then, nuclear fuel production techniques are introduced, and types of nuclear reactors are discussed. Importance of small modular reactors and their potential contribution in electricity generation are discussed. This is followed by nuclear cogeneration and hydrogen production processes. Finally, integrated nuclear energy systems for communities are provided over some case studies. Chapter 6 presents the solar energy systems. First, atmospheric and direct solar radiations are described with the solar radiation measurement methods. Then, solar radiation distribution in the world is presented. Next, solar energy applications are discussed with illustrative examples. Solar thermal and PV applications are introduced with their thermodynamic analysis techniques. Finally, photovoltaic thermal hybrid solar panels and their applications are given with the practical examples. Wind energy systems are introduced in Chapter 7. This chapter starts with historical development of the wind energy systems. This is followed by wind effect and global wind patterns which help create the wind power. Then, the types of wind turbines are introduced. Next, thermodynamic analyses of wind energy systems are provided with illustrative examples. Finally, some case studies and exergy maps for wind energy systems are shared with the readers. Chapter 8 deals with geothermal energy technologies. In this chapter, after introductory information about geothermal energy systems, their advantages and disadvantages are discussed with the readers. Then, power generation methods from geothermal energy are presented with illustrative examples. Finally, other applications of geothermal energy, such as heat pump, district heating, absorption cooling and hydrogen production are provided with practical examples. Biofuels and biomass energy systems are discussed in Chapter 9. This chapter starts with CO2 balance which makes biofuel and biomass are renewable sources. Details about combustion, gasification and pyrolysis are provided with illustrative examples. Waste-to-energy concept is introduced with a case study. Finally, biodigestion and micro-gas turbine applications are presented. Chapter 10 covers the water-related energy systems which are essentially hydro and ocean (marine) energies. First, hydro power generation systems are presented with illustrative examples. Types of hydro turbines are introduced. Then, ocean energy systems are discussed, which cover energy production with tides, waves, currents, ocean thermal energy, and salinity gradients. Here, energy sources and production techniques are presented in detail with practical example. In Chapter 11, energy storage methods are presented with the need of energy storage systems and their importance. Mechanical, thermal, chemical, electrochemical, magnetic and electromagnetic and biological energy storage techniques are discussed with their working principles. Chapter 12 presents the hydrogen energy system which are hydrogen production, storage and utilization. First, hydrogen production systems are introduced briefly, and then electrolysis process is discussed in detail with illustrative examples. Next, hydrogen storage techniques are presented. Finally, utilization of hydrogen is provided based on fuel cell applications. Chapter 13 introduces the integrated energy concept. System integration and analysis techniques are presented with illustrative examples. Multigeneration concept is also discussed with case studies. Chapter 14 aims to provide background for life cycle assessment of the energy systems. First, goals and scope of life cycle assessment are defined. Then, life cycle inventory analysis for energy systems is presented with illustrative examples. Finally, impact assessment and improvement analysis are given with practical examples.

Incorporated throughout are many analysis methodologies, illustrative examples, and case studies, which provide the students with a substantial learning experience, especially in areas of practical applications of energy systems. There are appendices included where unit conversion factors and tables and charts of thermophysical properties of various materials and substances in the International System of units (SI) are covered.

In closing, the assistance provided by of two doctoral students, Mert Temiz and Ali Karaca, of Prof. Ibrahim Dincer are highly acknowledged.

Ibrahim Dincer

Dogan Erdemir

Nomenclature

Symbols

A

Area (m

2

)

c

Specific heat (kJ/kg K)

D

Diameter (m, mm)

e

Specific energy (kJ/kg)

E

Energy (kJ)

Energy transfer rate (kW)

ex

Specific exergy (kJ/kg)

Ex

Exergy (kJ)

Exergy rate (kW)

F

Shape factor

g

Gravity (m/s

2

)

h

Specific enthalpy (kJ/kg)

Solar radiation (W/m

2

)

m

Mass (kg, ton)

Mass flow rate (kg/s, kg/h)

Molar flow rate (mol/s)

N

Number of moles

V

Velocity (m/s)

Volumetric flow rate (m

3

/s, L/min)

P

Pressure (kPa, bar), Power (kW)

Q

Heat transfer (kJ)

Heat transfer rate (kW)

R

Universal gas constant or solar radiation (kW/m

2

) or radius (m)

t

Time (s, min, h)

T

Temperature (°C, K)

s

Specific entropy (kJ/kg K)

S

Entropy (kJ/K)

u

Internal energy (kJ/kg)

v

Specific volume (m

3

/kg)

V

Volume (m

3

, L)

Work rate (W, kW)

x

Vapor quality

z

Elevation (m)

Greek Letters

Δ

Difference

ε

Emitted radiation

η

Efficiency

ρ

Density (kg/m

3

)

λ

Equivalence ratio

Ψ

Exergy index, exergy coefficient

τ

Transmitted radiation

Subscripts

0

Reference

abs

Absolute or adsorbed

ave

Average

b

Boundary

boil

Boiler

c

Compressor or compression or combustion

cc

Combustion chamber

ch

Charging period

com

Combustion

comp

Compressor

con

Condenser

d

Destruction

dest

Destruction

disch

Discharging period

down

Downward flow

dry

Dryer

elect

Electric

en

Energy

eva

Evaporator

ex

Exergy

g

Generator

gen

Generation

f

Final or fluid

fg

Fluid/gas mixture

H

High temperature

Hx

Heat exchanger

HRSG

Heat recovery steam generator

i

Inlet or initial or any stream

is

Isentropic

loss

Loss

in

Inlet

L

Low temperature

max

Maximum

min

Minimum

net

Net

o

Outlet

o

Outlet

p

Constant pressure or pump or piping

prod

Products

react

Reactant

ref

Reference

s

Source

sf

Solid/fluid mixture

sh

Shaft

t

Turbine, total

tur

Turbine

up

Upward flow

v

Constant volume

Abbreviations

ADP

Abiotic depletion potential

AC

Air conditioner

AP

Acidification potential

AFR

Air fuel ratio

BiPV

Bifacial photovoltaic

COP

Coefficient of performance

COVID

Corona Virus Disease

CSP

Concentrated solar power

EBE

Energy balance equation

EnBE

Entropy balance equation

EP

Eutrophication potential

ExBE

Exergy balance equation

ES

Energy storage

GC

Gas consumption

CC

Coal consumption

CNG

Compressed natural gas

COMM

Commercializability

DMFC

Direct methanol fuel cells

OC

Oil consumption

EMC

Electromagnetic Suspension System

EPS

Electromagnetic Pulse System

FC

Fuel cell

FLT

First law of thermodynamics

GDP

Gross domestic product

GFR

Gas-cooled fast reactor

GHG

Greenhouse emissions

GWP

Global warming potential

HE

Heat engine

HHV

High heating value

HP

Heat pump

HEX

Heat exchanger

HRSG

Heat recovery steam generator

HVAC

Heating, ventilation, and air conditioning

JC

Job creation

KE

Kinetic energy

LHV

Lower heating value

LNG

Liquid natural gas

LCA

Life cycle assessment

LCC

Life cycle costing

LED

Light-emitting diode

LFR

Lead-cooled fast reactor

LNG

Liquid natural gas

MBE

Mass balance equation

MED

Multi-effect desalination

MSR

Molten salt reactor

NG

Natural gas

NGC

Natural gas consumption

ODP

Ozone depletion potential

ORC

Organic Rankine cycle

PE

Potential energy

PEC

Photoelectrochemical

PEM

Polymer Electrolyte Membrane

PV

Photovoltaic

PVT

Photovoltaic and thermal

SB

Solid body

SCWR

Supercritical water-cooled reactor

SFR

Sodium-cooled fast reactor

SLT

Second law of thermodynamics

SMES

Superconducting Magnetic Energy Storage

SMR

Small modular reactor

SNG

Synthetic natural gas

SSSF

Steady state, steady flow

TC

Total consumption

TES

Thermal energy storage

TLT

Third law of thermodynamics

TR

Technology readiness

TSR

Tip-speed ratio

USUF

Uniform-state, uniform flow

VHTR

Very high temperature reactor

WAM

Weighted arithmetic mean

WGM

Weighted geometric mean

ZLT

Zeroth law of thermodynamics

About the Companion Website

This book is accompanied by companion website:

www.wiley.com\go\dincer\energysystems

This website includes

Appendices.

1 Energy and Environment Perspectives

1.1 Introduction

Humanity has been struggling with many global issues such as energy, water, food, education, pandemic and diseases, terrorism and wars, population increase, immigration and refugees, poverty, and environment as illustrated in Figure 1.1 that makes the world cry. This is primarily because of the anthropogenic activities where fossil fuels in global energy portfolio have played a critical, but damaging role. There have been various researchers and institutions making various lists of problems or ranking the global challenges, and they have more or less ended up with the same or similar items, ranging from energy to water and from food to environment. Almost all countries have been affected by one or more, or all of these items as presented in Figure 1.1. Among these, energy is of course listed one of the top-ranked challenges as it is essential to drive the sectors, economies, and hence societies for their activities. During the past a few years, it has been crystal clear to all of us that the COVID-19 pandemic has changed many tangible and intangible things in our daily life, personal relations, institutional arrangements, country affairs, energy matters, business, trade, politics, economy, education, social life, etc. Although each item has a unique impact on people’s lives, some of them, for example, energy, are affecting the rest of the items significantly. Energy is recognized as a significant necessity which is considered responsible for many issues in particular related to ecosystem, air, water, and food. For instance, traditional energy systems which use fossil fuels cause air pollution and water pollution issues. The emissions, in particular greenhouse gas (GHG) emissions, cause major environmental challenges, such as global warming (or greenhouse effect) and stratospheric ozone depletion. For example, due to the global warming we face water scarcity in many parts of the world causing crises in many sectors, including agricultural sector.

Figure 1.1 Global challenges affecting the people’s past, present and future.

Furthermore, each item given in Figure 1.1 is, no matter, of great importance. However, one may extract four out of them, namely clean energy, clean air, clean water, and clean food, that affected the past, are affecting the present, and will probably affect the future of humanity. Clean energy plays a key role among these four key humanity-needs as the nature and cleanliness of energy may badly influence the other three, namely air, water, and food. Here, clean energy primarily refers to renewable energy where we use renewable energy sources, such as solar, wind, geothermal, hydro, marine and biomass to generate clean outputs (for example, electricity, heat, and cooling) for daily sectoral applications. Energy is essentially needed for almost every operation or application or process in our daily life. Therefore, clean energy has a crucial role in providing clean air, clean food and clean water which will result in a more sustainable community.

Since the food chain from harvesting to the shelf is so diverse and there are many processes involved which are energy intensive and fuel consuming, they require huge amounts of energy and fuels, accounting for over 30% of the world’s total energy consumption. Of course, having more and more processed foods coming to our tables, due to the advanced preservation and processing technologies as well as rising population, will even increase this much more. For example, ammonia is one of the most essential inputs for agriculture since it is used as fertilizer, or agricultural machinery consumes a voluminous fuel for tillage. Also, water is the most significant input for agriculture and aquaculture. Pumps used in watering or oxygen generators used in aquaculture consume a considerably high amount of energy. On the other hand, the transportation of the agricultural products is an indispensable part of the food-supply chain. Clean transportation options will help achieve clean food and clean air targets. Moreover, electricity is consumed to preserve the food in the refrigerator. Consequently, energy, food, environment and water are really connected very much to each other. So, we need to find newly developed and innovative options to operate all these steps in a sustainable manner.

Although the Earth is called as the water planet, almost 99% of the water resources on the Earth are not usable by people. It is widely known that about 1% of the water sources is fresh water in a drinkable form which is largely found in lakes, rivers, and underground sources. In order to obtain fresh water from the remaining 99% of the unusable forms of water, water should be cleaned and hence desalinated accordingly, which again requires a significant amount of energy for operation. So, clean energy will really be the key to clean water, too. Finally, this shows us that it may not take too much time to be faced with the water crisis.

Energy itself is, no doubt, an essential need for people, and the amount of energy consumption has been ever-increasing in the world due to the increasing population, the rising living standards, and the comfort level requirements in almost all sectors. Today, most of the energy demands are met by fossil fuel-based systems, and the consumption of fossil fuels is also increasing day by day. Fossil fuels can be assumed to be one of the major contributors to environmental problems. The increasing energy consumption and environmental problems have compelled people to use energy more efficiently, especially in existing energy systems and to benefit from clean energy sources (renewables and nuclear).

We begin this chapter with the importance of energy and how to solve energy issues effectively. Next, the smart solutions to solve these issues are discussed. The role of engineering is essentially introduced and discussed for solving energy-based problems. Then, the introductory information on environmental issues, industrial ecology, and life-cycle assessment is presented. Finally, the importance of energy labeling is discussed along with some examples.

1.2 Importance of Energy

It is a common fact that life is impossible without energy which is an essential driver for anything and everything. Energy is vital for our daily life and sectoral activities. Some examples may be introduced as follows:

In our home for lighting, appliances, televisions, computers, air conditioners, etc.

In factories to power the manufacturing processes; and

In transportation for cars, trucks, ships, airplanes to transport people and goods.

The energy demand in the world has been ever-increasing due to the growing population and enhanced living standards. Figure 1.2 demonstrates the global changes in the world energy consumption (in Figure 1.2a), world gross domestic product (Figure 1.2b), and world population with respect to years (Figure 1.2c). The world’s population is also projected to be around 10 billion by the year 2050, as seen in Figure 1.2a. Most of the population will eventually require food, energy, shelter, water, etc. more than what people have today. The increase in the population definitely results in a substantial amount energy consumption. As seen from Figure 1.2a, by 2050, it is expected to drastically increase in the global energy use approximately by 50%. The biggest contribution in this increase is done by non-OECD economic growth and population. Also, the increasing population will require more domestic products. Figure 1.2b shows the historical and projected data for world gross domestic product changes. It is expected to increase more than double. These numbers clearly show that urgent action is really required for a sustainable future, especially in energy production and consumption.

Figure 1.2 The projections of (a) the world energy consumption, (b) gross domestic product, and (c) population (data from [1]).

1.3 Energy Issues

All sectors have relied on energy as a constant source of power. Over time, energy has become more important, especially after the industrial revolution. Many economic domains and areas have been governed by it, such as relationships, business deals, wars, terrorist activities, etc. At present, it dominates more than ever and will certainly dominate far more in the future. The present civilization has a fundamental responsibility to deal fairly and diligently with this issue.

The increasing world population and the rising living and working standards in all sectors have been the reasons behind the worldwide ever-rising energy consumption. Figure 1.3 illustrates the total amount of energy consumption around the world by source from 1965 to 2020. As mentioned previously, the global energy consumption has increased significantly every year. Figure 1.3 also highlights that fossil fuels cover nearly 65% of the global energy demand. Additionally, while the decrease in energy consumption in 1972–1975, 1979–1983, and 2008 have occurred due to economic recession, it has occurred due to the COVID-19 pandemic occurred in 2020. From 1965 to 2020, energy consumption increased approximately four times.

Figure 1.3 Total energy consumption of the world by sources (data from [2]).

Fossil-based fuels essentially meet almost two-third of the global energy demand. They also have some risks due to their limited and nonhomogeneous reserves, environmental impacts, and energy security concerns. These risk factors have forced people toward alternative energy sources and systems such as renewable energy sources. Traditional energy systems dramatically pollute the environment, so, today, we are talking about the net zero emissions target, clean energy technologies, etc. Also, with the oil crisis that emerged in October 1973, the interest in alternative energy sources has increased significantly. Especially, solar domestic hot water systems and other solar space heating systems have become prevalent after the oil crisis. The use of renewable energy sources has increased significantly over the past decade. Despite the magnificent advantages of renewables in terms of energy security and environmental impact, the biggest disadvantage in their use is that they are mostly non-continuous energy sources, such as solar and wind, due to their fluctuating nature [3].

Another issue with energy is the difference between the energy supply and demand profiles. The energy demand profiles vary with respect to the sectors (residential, industrial, commercial, etc.) and time frame (daily, weekly, seasonal, yearly etc.). For instance, when the weekly energy demand profiles of the industrial and commercial sectors are considered, their energy demands tend to decrease on the weekends due to lowering activities in these sectors. In the residential buildings, against to the commercial and industrial sectors, the energy demands are higher on the weekends due to increasing time spent in residential units and indoor activities. When the yearly energy demand profile is taken into consideration for all sectors, it is quite higher during the summer due to the intensive air conditioner (AC) usage. That is why the highest electricity consumption rates are observed in the summer months.

In addition to these two issues, the peak loads are another issue faced in the energy field. Fluctuating trend in energy demand means peak energy loads, which requires a substantially higher amount energy according the off-peak and average loads. Peak loads are also seen in the short time depending on the time frame considered. For example, the highest cooling loads which are almost 50% higher than the average load, are seen 2–4 hours in a day. On a yearly basis, the highest electricity consumption is seen in the few hottest weeks in summer in many countries. In order meet the peak load, high-capacity devices should be included in the buildings for micro scale (buildings, factories, etc.). For macro scale such as communities, regions, countries, extra power plants or energy imports are required to meet the peak energy demands. Extra power plants and energy imports bring with it a high cost for energy supply. The different tariff structures, called triple tariff or multi tariff, are used to cover a part of this high-cost energy. Also, the time-of-use tariffs aim to promote to reduce energy consumption for savings during peak periods and to shift the peak demand from peak hours to off-peak hours. In order to avert those issues in the energy use and reduce the environmental impact due to energy consumption, we need to find smart solutions which will be presented forthcoming sections.

1.4 Environmental Issues

Energy supply and demand are related not only to problems such as global warming but also to such environmental concerns as air pollution, ozone depletion, forest destruction, and emissions of radioactive substances. All of them are called environmental impact categories. All environmental impact categories must be taken into consideration if human society is to develop in the future while maintaining a healthy and clean environment. Much evidence suggests that the future will be negatively impacted if people and societies continue to degrade the environment. Figure 1.4 shows the energy related CO2 emissions in the world. CO2 emissions have exponentially increased, and it is therefore expected that it will continue increasing with the increasing energy consumption. If current policy and technology trends continue, global energy consumption and energy-related carbon dioxide emissions will increase through 2050 as a result of population and economic growth. Renewables will be the primary sources for new electricity generation, but natural gas, coal, and increasingly batteries will be used to help meet load and support grid reliability. Oil and natural gas production are still expected to continue in a growing manner, mainly to support increasing energy consumption in developing countries, including Asian economies.

Figure 1.4 Energy related (a) carbon dioxide (CO2) emissions, (b) carbon intensity and (c) energy intensity (data from [1]).

There is an intimate connection between energy, the environment, and sustainable development. A society seeking sustainable development ideally must utilize only energy resources that cause no environmental impact (e.g., which release no emissions or only harmless emissions to the environment). However, since all energy resources lead to some environmental impact, it is reasonable to suggest that some (but not all) of the concerns regarding the limitations imposed on sustainable development by environmental emissions and their negative impacts can be overcome through increased energy efficiency. A strong correlation clearly exists between energy efficiency and environmental impact since, for the same services or products, less resource utilization and hence pollution are normally associated with higher efficiency processes.

Achieving solutions to the environmental problems that we face today requires long-term planning and actions, particularly if we are to approach sustainable development. In this regard, renewable energy resources appear to represent one of the most advantageous solutions. Hence, a strong connection is often reported between renewable energy and sustainable development. Environmental considerations have been given increasing attention in recent decades by energy industries and the public. The concept that consumers share responsibility for pollution and its impact and cost has been increasingly accepted. In some jurisdictions, the prices of many energy resources have increased over the last 20 years, in part to account for environmental remediation costs. It is really necessary to look at some major environmental issues which are listed below:

Acid rain: It results when sulfur dioxide and nitrogen oxides are emitted into the atmosphere and transported by wind and air currents. The combustion of the fossil fuels is the main contributor of acid rain.

Stratospheric ozone depletion: it is used for defining the thickness of the ozone later in the stratosphere.

Global warming and climate change: Global warming and climate change occur due to greenhouse emissions created by human activities.

Hazardous air pollutants: include carbon monoxide, lead, nitrogen oxide, ozone, sulfur dioxide etc., which are mainly formed by burning fossil fuels.

Poor ambient air quality: Air quality is defined over oxygen, carbon monoxide, carbon dioxide, and nitrogen oxide and hazardous air pollutants in the air. Combustion of fossil fuels and husbandry results in a poor ambient air quality.

Water and maritime pollution: occur when the mixture of chemical and trash are disposed to the lakes, rivers, sea, and oceans. This pollution causes damages in the environment and living organisms in the water. It breaks down the balance of the world.