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In this chapter, the authors’ guiding principles are compared to the strategy adopted by Europe, followed by an exploration of the ways in which the European Union could become a real crucible for the ecological transition.

This chapter discusses the various methods available for the measurement of local crystal symmetry and of local vibrational motion in ferroelectric systems. A basic disadvantage of many of these techniques is that they make use of properties of ions, such as paramagnetism and nuclear quadrupole moment, which are not possessed by the majority of ions which make up the more common ferroelectrics and antiferroelectrics. This implies a necessity of doping, which in turn can modify the local environment under study and lessen the ability to investigate properties of the nominally pure material. On the other hand, the methods also have advantages including great sensitivity and the ability to probe in detail the often very important roles played by impurities and defects in ferroelectrics. This chapter also considers basic concepts of nuclear magnetic resonance and some experimental findings, electron paramagnetic resonance, Mössbauer spectroscopy, optical spectroscopy, electronic band structure, impurity spectra, colour centres and polarons, stimulated emission, excited-state polarization, photovoltaic effects, and the photorefractive effect.

Chapter 1 begins by stressing the severity of climate change (CC) and showing how, contrary to popular belief, atomic energy is not a viable solution to CC. Many scientists and most market proponents agree that renewable energy and energy efficiencies are better options. The chapter also shows that government subsidies for oil and nuclear power are the result of flawed science, poor ethics, short-term thinking, and special-interest influence. The chapter has 7 sections, the first of which surveys four major components of the energy crisis. These are oil addiction, non-CC-related deaths from fossil-fuel pollution, nuclear-weapons proliferation, and catastrophic CC. The second section summarizes some of the powerful evidence for global CC. The third section uses historical, ahistorical, Rawlsian, and utilitarian ethical principles to show how developed nations, especially the US, are most responsible for human-caused CC. The fourth section shows why climate-change skeptics, such as “deniers” who doubt CC is real, and “delayers” who say that it should not yet be addressed, have no valid objections. Instead, they all err scientifically and ethically. The fifth section illustrates that all modern scientific methods—and scientific consensus since at least 1995—confirm the reality of global CC. Essentially all expert-scientific analyses published in refereed, scientific-professional journals confirm the reality of global CC. The sixth section of the chapter shows how fossil-fuel special interests have contributed to the continued CC debate largely by paying non-experts to deny or challenge CC. The seventh section of the chapter provides an outline of each chapter in the book, noting that this book makes use of both scientific and ethical analyses to show why nuclear proponents’ arguments err, why CC deniers are wrong, and how scientific-methodological understanding can advance sound energy policy—including conservation, renewable energy, and energy efficiencies.

Chapter 2 begins by outlining the origins and history of nuclear technology. It goes on to show how claims that nuclear fission is a low-carbon technology are false. Such claims rely on a variety of flaws, the first of which is the fact that most nuclear-emissions studies count greenhouse-gas (GHG) emissions only at point of electricity use, rather than from the entire, 14-stage nuclear-fuel cycle. By thus “trimming the data” on nuclear-related GHG emissions, proponents falsely portray fission as a “green,” low-carbon technology. In reality, once one counts GHG emissions from all nuclear-fuel-cycle stages, fission has roughly the same GHG emissions as natural gas. Another flaw with the claim that nuclear GHG emissions are low is that it fails to take into account the much higher emissions that arise from using low-grade uranium ore to create reactor fuel. Third, those who claim that nuclear GHG emissions are low are inconsistent in that they fail to apply their own logic (that we should implement energy technologies with low GHG emissions) to electricity sources (such as wind and solar photovoltaic) that are much better GHG-emissions avoiders than is nuclear power. A fourth problem is the fact that reactors generate only about 25 percent more energy, in their lifetime, than is required, as input, to the 14 stages of their fuel cycle. A fifth flaw of those who propose using nuclear energy to address CC is their failure to take account of the fact that reactors massively increase risks of nuclear proliferation and terrorism. Using atomic energy to help combat CC worsens another, and equally catastrophic, energy problem: nuclear proliferation and nuclear terrorism. A sixth flaw of using fission to address CC is failure to take account of the practical difficulties of tripling the number of global reactors. For all these reasons, the chapter shows that commercial atomic energy cannot address CC.

Chapter 6 discusses many CC solutions that avoid nuclear fission. Because wind and solar-PV power are fully developed, are relatively inexpensive, and can provide electricity (which offers the greatest flexibility in energy use, including supplying electricity for plug-in hybrids), this chapter considers mostly wind and solar PV. This chapter lays out 10 arguments for using renewable energy and efficiency programs, rather than nuclear fission, to address CC. First, it shows that energy efficiency and conservation are the cheapest ways to address CC. It also shows that both wind and solar photovoltaic are cheaper than atomic energy. Not only do market proponents confirm that renewable energy is cheaper than nuclear fission, but renewable energy is also becoming progressively cheaper, while fission is becoming progressively more expensive. The chapter illustrates that renewable-energy sources could supply all global energy, while fission could not, and that renewable-energy sources can be implemented more quickly than atomic power. Renewable-energy sources, unlike nuclear fission, are sustainable, low-carbon technologies that would also make the nation and the planet more militarily secure than could nuclear power. Finally, the chapter shows how the transition to 100-percent-renewable energy can be made easily and smoothly.

According to Michael Zarin, Director of Government Relations with Vestas Wind Systems, there is nothing “alternative” about wind power anymore (Biello, 2010). After all, wind generation is the most cost-effective option for new grid-connected power in markets like Mexico, South Africa, New Zealand, China, Turkey, Canada, and the United States (Renewable Energy Policy Network [REN21], 2016). At 433 GW of cumulatively installed capacity in 2015 worldwide, more than half was added in the past 5 years (REN21, 2016). This technology may be used by individuals, communities, and utilities. It can be grid-connected or off- grid, and be used onshore or offshore. This chapter examines the influences and evolution of the Danish wind transition, highlighting how ingenuity and often less-obvious incremental advances produced a world-class industry. It reveals how citizens can be important catalysts of energy system change. The case also indicates that innovations can emerge in practices and policy, not just technology, science or industry. Denmark is a cultural and traditional technology leader for modern wind power. This country of roughly 5.6 million people and GDP of approximately $65 billion in 2016 (ppp) (Central Intelligence Agency [CIA], n.d.) is where today’s dominant, wind turbine design was established and where state-of-the art wind technology testing centers are based. It is also the site of the first, commercial-scale offshore wind farm, built in 1991. Denmark has a world-class hub for wind energy technology (Megavind, 2013; State of Green, 2015; Renewable Energy World, 2016). Top-ranked companies like Vestas, LM Wind Power, Siemens Wind Power, A2SEA, and MHI Vestas Offshore Wind are among those that base core parts of their global operations in Denmark. A close network of wind engineers and their professional affiliates drives the industry, which includes ancillary services and subcomponent supplies. Wind energy technology also represents one of Denmark’s top-ranked exports (United Nations Comtrade, n.d.). Currently, Denmark has more wind power capacity per person than does any other country in the world (REN21, 2017). This Northern European nation is on track to derive 50% of its electricity from wind power by 2020.

This chapter reviews the history and the state-of-the-art research of the ferroelectric photovoltaic effect, in particular the role of DWs. Over the last decade, the field of ferroelectric photovoltaic effect has been experiencing a significant revival. Ferroelectrics can spontaneously generate a short-circuit current under uniform illumination owing to the asymmetric momentum distribution of the nonequilibrium photo-excited carriers in the k-space, termed the bulk photovoltaic effect. In contrast to the conventional photovoltaic effect based on a gradient of the chemical potential, the ferroelectric photovoltaic effect exhibits distinctive features. Although the solar energy harvesting based on ferroelectric materials suffers a low power conversion efficiency due to their poor light absorption in the visible range and high resistance, the progress in oxide thin film growth has significantly promoted the efficiency of ferroelectric solar cells in recent years. Meanwhile, the coupling of light with intrinsic degrees of freedom offers a fertile and rich playground to explore the new functionalities of (multi-)ferroelectrics and to develop related applications. In this regard, light-induced reversible ferroelectric switching and domain wall motion have been recently achieved.

This chapter is divided into three parts: LEDs, light-emitting transistors, and photovoltaics. The LED section first defines the relevant terminology before discussing the requirements for different devices. White light is a technologically challenging area for polymer electronics, and the use of phosporescent materials to improve white LEDs is described. Two forms of light-emitting transistors are then discussed as an alternative means of generating light in devices. Photovoltaics are a very topical area of research, and the physics behind the photovoltaic effect and its application in organic materials are considered. The electronics of devices are mentioned; as are morphologies and structures that can be used to generate better devices, along with the limitations on performance.

After a review of fundamental notions such as absorption, emission, and the properties of excited states, the chapter introduces excited-state electron transfer. Several examples are presented, using molecules to realize photodiodes, light-emitting diodes, and photovoltaic devices, and even harnessing photochemical energy for water photolysis. The specificities of ultrafast electron transfer are outlined. Energy transfer is then defined, starting from its theoretical description, and showing its involvement in photonic wires or molecular assemblies realizing an antenna effect for light harvesting. Photomagnetic effects, such as the modification of magnetic properties after photonic excitation, are then studied. The examples are taken from systems presenting a spin cross-over, with the LIESST effect, and from systems presenting metal–metal charge transfer — in particular, in Prussian Blue analogues and their molecular versions.

There are two basic approaches for using solar energy to generate electricity. The first type, solar photovoltaic (PV) energy, uses semiconductors to convert sunlight into electricity. Crystalline silicon semiconductors are the most common type in use. The second approach is called concentrating solar power (CSP), also referred to as solar thermal. Basically, CSP uses mirrors to concentrate sunlight and generate steam, which is used to power a turbine. The most common method employed commercially is the parabolic trough, where the mirrors are horizontally disposed in a parabolic shape. Solar PV is more commonly used commercially because of high capital costs for building a CSP power plant. Solar PV has experienced rapid growth over the last ten years, increasing by more than twentyfold in the United States. Growth for CSP has increased threefold over the same ten years, but no growth over the last four years. Spain and the United States lead the world in commercial CSP plants.

This chapter explores how the fifty US states generate electricity, and the analysis shows significant variation in how electricity is generated state-by-state. While coal was formerly the dominant fuel for generating electricity, natural gas surpassed coal in 2015. Although thirteen states still produce more than 50% of their electricity from coal, fourteen states generated less than 5%. There have been no new nuclear power plants built since 1996, but seven states still generated more than 40% of their electricity from this resource. In renewable energy, wind and solar are gaining in importance. Fourteen states now generate more than 10% of their electricity from wind, and three states more than 30%. Solar energy is also growing, but mostly in the sun-drenched states of California, Arizona, Nevada, and North Carolina, which account for 67% of US solar energy. Hydroelectric is also important, and five states generated more than 50% of their electricity from hydroelectric plants.

The mechanism of the photovoltaic effect of metal nanoparticles in contact with inorganic semiconductor nanoparticles is proposed, first for the surface plasmon-induced generation of hot electrons in metal nanoparticles and then for the transfer of the hot electrons to inorganic semiconductor nanoparticles to ultimately bring about charge separation. This explanation is reinforced by knowledge of the photovoltaic effect of Ag nanoparticles on AgX nanoparticles, referred to as the photographic Bequerel effect, which has been studied and analysed for more than a century in photographic systems. This mechanism is verified by the fact that the smallest photon energy for the photovoltaic effect corresponds to the difference between the work function of a metal and the electron affinity of a semiconductor in both Au/TiO₂ and Ag/AgBr systems in photography. Several other possible mechanisms for the photovoltaic effect are also discussed.

After a review of fundamental notions such as absorption, emission and the properties of excited states, the chapter introduces excited-state electron transfer. Several examples are given, using molecules to realize photodiodes, light emitting diodes, photovoltaic cells, and even harnessing photochemical energy for water photolysis. The specificities of ultrafast electron transfer are outlined. Energy transfer is then defined, starting from its theoretical description, and showing its involvement in photonic wires or molecular assemblies realizing an antenna effect for light harvesting. Photomagnetic effects; that is, the modification of magnetic properties after a photonic excitation, are then studied. The examples are taken from systems presenting a spin cross-over, with the LIESST effect, and from systems presenting metal–metal charge transfer, in particular in Prussian Blue analogues and their molecular version.

This chapter describes the operating principles of photoconductive and photovoltaic detectors based on III–V semiconductors. The electrical characteristics of both photodiodes and majority carrier barrier structures are discussed starting with the diffusion equation. The chapter outlines the figures of merit used to evaluate the performance of infrared photodetectors including the responsivity, dark current density, and normalized detectivity. It discusses bulk-like and type II superlattice photodetectors and how the multistage arrangement of interband cascade detectors (ICDs) can reduce the dark current density at the expense of a lower responsivity. Detectors that employ intersubband optical transitions, namely, quantum-well infrared photodetectors and quantum cascade detectors, are also discussed. The chapter considers how the dark-current density can be suppressed in resonant-cavity and thin waveguide-based detectors. It concludes with a discussion of the requirements for high-speed operation and an overview of novel types of detectors that draw their inspiration from III–V semiconductor devices.

Increasing energy access is recognized as a priority contribution to development. Innovative approaches to providing energy access have been successfully tried, and business models for the dissemination of decentralized renewable energies could be ready for large-scale replication. The decrease in the cost of some renewable energy technologies, the arrival of new technologies like LEDs, and the widespread use of mobile phones—which are used for micro-banking in developing countries—are drastically reducing the cost of access to basic energy services. Electrification seems to be entering a new era of massive diffusion of basic systems like solar lanterns. Mini-grids with hybrid generation can supply remote villages in a cost-effective way. But the quality control and the maintenance of these systems are still an issue for the long-term sustainability of these markets.

Solar and wind power have low power densities. Large areas will be required to generate the electrical energy that we are using right now. These energy sources are intermittent, although sunshine is reasonably predictable in desert climates. Even in these ideal locations, fixed rooftop PV can only be used to meet a relatively small proportion of total electrical demand. Solar thermal with molten salt storage has a higher efficiency, and can better match electrical demands in these places. For wind turbines to generate their advertised or rated power, winds have to be blowing at about 12 m/sec (20 kt or 24 mph). In the United States, except in mountain passes and the Texas panhandle, this does not appear to happen very often. A simple test of whether a given renewable energy source is practical is to check whether it can meet the electrical demands of a single house.

Energy from the Sun leads to direct heating of the Earth, and also to secondary forms of energy in winds, waves and hydroelectricity. Long-term energy resources in the Earth and its motions include tides, geothermal energy, fission fuels, and in deuterium that may potentially be used to power nuclear fusion reactors. We are interested in energy sources that will last on a time scale of thousands of years, and further, that will not interfere with other important aspects of life on Earth, such as clean air and water in abundant supply. Plants grew by photosynthesis starting in the carboniferous era, about 300 million years ago, and the decay of some of these, instead of oxidizing back into the atmosphere, occurred underground in oxygen-free zones.

The basic principles of solar energy systems are considered, allowing further analysis of devices, either photovoltaic or solar thermal, in later parts of the book. A consistent nomenclature on topics as diverse as thermodynamics and light absorption gives the reader a unique perspective on solar energy principles. A brief introduction to light absorption, photovoltaic systems and solar thermal systems is given, so the reader can appreciate more detailed information presented later in the book. This textbook was developed after teaching a course of the same name for several years and it was found that a short introduction to all the principles for photovoltaic and solar thermal applications is required early in the course so that the reader (student) can fully comprehend the subsequent more detailed discussion. This chapter was written with this in mind.

Light absorption and how it generates electrical current or heat is discussed. The amount of light absorbed, and its relation to the absorption spectrum is considered, to demonstrate how much current is generated in a solar cell. Details of the absorption spectrum are discussed and how the band gap energy is determined so that the ultimate performance of a solar cell can be appreciated. Both direct and indirect band gaps are considered and their effect on the absorption spectrum is presented to show why silicon-based photovoltaic devices suffer in power conversion efficiency. Finally, the absorption of radiation to generate heat is considered and the peculiar properties of a selective surface used in solar thermal devices are highlighted.