Future Energy

Improved, Sustainable and Clean Options for Our Planet

Trevor M. Letcher

• Editore: Elsevier
• Anno: 2020
• ISBN:
  9780081028872
• Edizione: 3
• Argomento: Technology & Engineering
• Categoria: Power Resources

Future Energy: Improved, Sustainable and Clean Options for Our Planet, Third Edition provides scientists and decision-makers with the knowledge they need to understand the relative importance and magnitude of various energy production methods in order to make the energy decisions necessary for sustaining development and dealing with climate change. The third edition of Future Energy looks at the present energy situation and extrapolates to future scenarios related to global warming and the increase of carbon dioxide and other greenhouse gases in the atmosphere.

This thoroughly revised and updated edition contains over 40 chapters on all aspects of future energy, with each chapter updated and expanded by expert scientists and engineers in their respective fields.

• Provides readers with an up-to-date overview of available energy options, both traditional and renewable, as well as the necessary tools needed to make informed decisions
• Covers a wide spectrum of future energy resources presented in a single book with chapters written by experts from each particular field
• Includes many new chapters that cover topics on conventional oil and fossil fuels, a new section on energy storage, and a look at new energy

Part 1

Introduction

Outline

1. Introduction With a Focus on Atmospheric Carbon Dioxide and Climate Change

1

Introduction With a Focus on Atmospheric Carbon Dioxide and Climate Change

Trevor M. Letcher ^{1 , 2 1} Department of Chemistry, University of KwaZulu-Natal, Durban, KwaZulu-Natal, South Africa ² Laurel House, Stratton on the Fosse, United Kingdom

Abstract

In this chapter, the focus will be on the rapid building up of greenhouse gases in our atmosphere, resulting in global warming and climate change. The main greenhouse gas is carbon dioxide, and its concentration has increase almost over 50% since preindustrial times. Much of this is due to the burning of fossil fuel to produce energy. Renewable energy in needed to significantly reduce our dependence on fossil fuel. This is followed by a discussion on the options we have for our main energy needs: electricity generation and transport fuel. A significant fraction of our renewable energy must come from solar energy, wind and hydrothermal energy; the latter two are, in reality, secondary effects of solar energy. In spite of scientists pointing out the urgency in replacing fossil fuel, progress is slow. Finally, we look at the big question: how can we reduce the stranglehold that fossil fuels have on our economy and lives?

Keywords

Energy beamed from space; Nuclear fission energy; Nuclear fusion energy; Renewable energy; Solar energy; Wind energy

1.1. Introduction

In this introductory chapter, we look at

1. • the driving forces behind the need to consider new forms of energy;
2. • the looming problem of global warming and climate change;
3. • the options for electricity generation and for transport fuel;
4. • the energy situation today;
5. • thermodynamics and sustainable energy,
6. • why solar energy is so very important and
7. • the big question: how can we reduce the stranglehold that fossil fuels have on our economy and lives?

The energy choices we make will depend on where we live, the size of our population, and also on the types of energy sources that are available. For example, people in Iceland will consider expanding their renewable sources of geothermal and wind energy, whereas those living in South Africa will certainly consider solar energy, among many other possibilities.

At the same time, account should be taken of the polluting nature of the energy source and it is our responsibility to assure that whatever energy source we utilize, we do it in an environmentally sound manner. And if one cannot steer totally away from fossil fuels, the resultant carbon dioxide and other pollutants should be either sequestered and stored or utilized and not emitted to the atmosphere.

1.2. Why is it important to consider our future energy options?

1.2.1. Society's needs

As the population of the world increases and as developing countries advance, so energy needs increase. The world's population is increasing–it was 3 billion (3 × 10⁹) in 1960, 6 billion in 2000, 7.6 billion in July 2018, and is expected to reach between 9 billion and 10 billion by 2050. The annual rate of population growth reached a peak of 2.2% a ⁻¹(where “a” refers to annum) in 1963, but by 2018, it had declined to 1.09% a ⁻¹ [1]. The population is growing at a rate of 83 million people per annum.

The expected growth rate in energy demand over the next 20 years is greater than the growth rate of the population and this is largely due to increased electricity production by developing nations. The electricity generation is expected to increase from 25.1 × 10¹⁵ Wh in 2017 to 29.2 × 10¹⁵ Wh in 2030, which is equivalent to an average energy increase of 1.3% a ⁻¹ [2]. This additional energy supply must be found and preferably in the form of renewable energy.

1.2.2. The need for a sustainable, safe, and nonpolluting energy source

The present world electrical energy generation is dominated by fossil fuel (see Table 1.1), which unfortunately is not sustainable in the long term. Furthermore, the combustion of fossil fuel is a major cause of air pollution. The picture is confusing because we are living in an age with an apparent glut of fossil fuel. Coal and conventional gas continue to be relatively easy to extract. Unconventional gas has experienced a recent boom because of horizontal drilling and hydraulic fracturing techniques. At the same time, oil is becoming more and more difficult to extract in spite of new drilling techniques. Somehow the stranglehold must be broken and renewable energy is our only option. Even if we could replace fossil fuel for electricity generation, there is another problem, and that is the need for a sustainable, safe, and nonpolluting liquid fuel for air travel and vehicular transport. This is of particular concern as the transport and production of oil can create serious environmental problems, and names such as Exxon Valdez (1989), Torrey Canyon (1967), Niger Delta (1970–2000), and Deepwater Horizon (2010) have become bywords for environmental disaster.

Table 1.1

Total global electrical energy generation percentages for 2015 [2].

Type of energy	Electrical energy generation/%
Liquid (oil)	3.8
Coal	40.2
Natural gas	22.3
Nuclear	10.8
Renewables, including hydroelectric	23.0

The total global energy consumption (Table 1.2) paints a similar picture to the global electricity generation with the domination of fossil fuel. Furthermore, the spread of energy types involved has changed little over the past 7 years [3].

With the recent development of shale gas reserves, especially in the United States, there has been a shift in thinking about exploiting fossil fuel. The argument is that burning natural gas (largely methane) is better for the planet than burning coal. This is true because the amount of CO₂ produced from burning CH₄, per unit energy (50 g MJ ⁻¹) is less than it is for coal (92 g MJ ⁻¹) and moreover coal burning produces particulates. But burning CH₄ still produces CO₂:

CH₄ + 2O₂ = CO₂ + 2H₂O

and contributes to climate change.

Replacing fossil fuels is going to be a mammoth task. At present, energy sources other than fossil fuels make up less than 20% of global energy consumption (see Table 1.3). These include nuclear fission, hydroelectricity, biomass, and renewable sources, such as wind, solar, geothermal.

Replacing gasoline, diese...