Most renewable energy sources depend on the sun and so vary with time and ambient conditions. Hence a consistent supply of renewable energy requires energy storage. The main approaches to storing renewable energy are described and quantified. Pumped hydro, compressed air and flywheels are discussed. Storing heat in the fabric of buildings and hot water using sensible heat are described. The increasing importance of phase change materials to store energy through latent heat is recognized. Battery technology is developing very fast; the principles of lithium-ion batteries are explained, together with their advantages and disadvantages. The various materials currently used for the positive electrode are listed. The electrochemistry of various battery technologies is summarized as well as how a large number of cells are connected to form are a useful store of energy. The principle of flow batteries is demonstrated and approaches to the estimation of the lifetime of a lithium-ion battery discussed. The chapter is supported by 10 examples, 16 questions with answers and full solutions in the accompanying online material. Further reading and online resources are identified.

This chapter considers infringement proceedings, normally brought by the Commission against a Member State before the Court of Justice for not complying with EU law. Actions can only be brought against the State. However, the State is responsible for the legal acts and administrative practices of any State agency. There are three stages to the proceedings. The first is an informal stage where the Commission sees if there is a case to answer and, if so, seeks resolution with the State. In the second, the Commission issues a letter of formal notice, setting out the breach and what compliance requires. In the third, the Commission issues a reasoned opinion giving a reasonable period for compliance. The case only goes to the Court if there is no resolution by the end of the third stage. The Commission can also go to the Court to seek damages against the State in two circumstances: the State has failed to transpose a Directive or it has failed to comply with an earlier judgment of the Court. The sanction will usually take the form of a lump sum and penalty payments, which are recurring daily fines that continue as long as the breach.

We often give students at WIDA an assignment to write an essay titled “Diplomacy Is the World’s Best Hope.” Now it is my turn. The good news for me is that, if you have come this far in the book, you do not need to be persuaded in the value of diplomacy. Many political leaders around the world profess to appreciate diplomacy, too, but few bother to build or strengthen their countries’ diplomatic capacities, perhaps hoping that problems will somehow work themselves out. I will never stop repeating that the world needs highly skilled and effective diplomats, and the sooner those in power realize that — and do something about it — the better we all will be. I know of no better recipe to make the world less of a mess.

Diplomacy is a highly complex, multifaceted and often unpredictable profession. By definition, it seeks to overcome differences between and among countries, and those distinctions run the risk of turning into discord, or even conflict, without a playing field that has mutually accepted rules and norms. This is the role of diplomatic protocol, a system of standards, rules and regulations governing the conduct of international relations. It brings order and predictability to the work of diplomats by providing a roadmap or framework, so they can focus on the substance of negotiations and high-stakes decisions. It has been called “the oil in the gears of diplomacy” and credited with creating a “safe space that allows diplomacy to succeed.” While tradition has always had a special place in diplomacy, protocol’s role is hardly limited to old-fashioned pomp and circumstance. It has practical aspects meant to make diplomatic work more effective.

The second edition of this popular textbook has been extensively revised and brought up-to-date with new chapters addressing energy storage and off-grid systems. It provides a quantitative yet accessible overview of the renewable energy technologies that are essential for a net-zero carbon energy system. Covering wind, hydro, solar thermal, photovoltaic, ocean and bioenergy, the text is suitable for engineering undergraduates as well as graduate students from other numerate degrees. The technologies involved, background theory and how projects are developed, constructive and operated are described. Worked examples demonstrate the simple calculation techniques used and engage students by showing them how theory relates to real applications. Tutorial chapters provide background material supporting students from a range of disciplines, and there are over 150 end-of-chapter problems with answers. Online resources, restricted to instructors, provide additional material, including copies of the diagrams, full solutions to the problems and examples of extended exercises.

Actions in cyberspace by governments, businesses, NGOs and other players have become part of international relations and international security. Those actions reflect countries’ national interests and affect their bilateral and multilateral diplomatic relationships. This has led to the rise of cyber diplomacy, the activity of deploying international cooperation in cyberspace and using actions in cyberspace to achieve foreign-policy goals. The main focus of cyber diplomacy in its early stages is trying to forge a way to regulate state behavior and prevent and regulate conflict in cyberspace. Some governments have extended their cyber diplomacy portfolios to include the foreign-policy implications of new technologies. Both traditional tools from the diplomacy toolbox and new technologies are needed to build and maintain international cooperation in cyberspace. Cyber diplomacy is not the activity of using digital tools to accomplish traditional foreign-policy objectives–that is the definition of digital diplomacy.

In Van Gend en Loos and Costa, the Court stated that EU law was an autonomous legal order which limited the sovereignty of member States. These EU law qualities prevent other laws determining central elements of EU law (‘autonomy of EU law’); grant precedence to EU law over national law (‘primacy of EU law’); allow EU law alone to determine when there is a conflict between it and national law and the consequences of that (‘pre-emption’); and require national authorities to ensure that the EU legal system functions effectively and its authority is sustained (‘fidelity principle’). Historically, most national courts have accepted the authority of EU law over national law, subject to three constraints. First, EU law should not violate fundamental rights recognised in their respective constitutions. Secondly, if it generates significant consequences for the national democracy, the EU law must not be clearly ultra vires. Thirdly, a number of courts will not accept EU law primacy on matters that go to that State’s constitutional identity, most notably those issues over which that court believes national parliaments have the necessary democratic pedigree.

Multilateral diplomacy is defined as the management of relations among three or more nation-states, both within and outside international organizations. The main value of multilateral diplomacy is its ability to reduce the complexity of international relations in everyday life, including traveling, sending mail and solving crimes across borders. It produces agreements that are much more practical and less costly than a web of bilateral arrangements between individual countries, and it sets common standards that enable collaboration among scientists, engineers and businesses around the world. In addition to formal international organizations, multilateral diplomacy is practiced in informal or ad hoc groups and coalitions. There are few things in multilateral diplomacy more important than who writes the rules, who sets the agenda, and who holds the pen during negotiations.

Political tradecraft is a set of duties, responsibilities and skills required of diplomats who work in political affairs. It is the main instrument in the diplomatic tradecraft toolbox, which also includes, among other tools, economic tradecraft, commercial diplomacy, consular affairs and public diplomacy. Political officers work both at diplomatic missions abroad and at headquarters, such as their ministry of foreign affairs or the State Department. Although there are some differences in a political officer’s daily duties at home compared with those abroad, they all participate in managing international relations and implementing foreign policy. Those who rise to the most senior positions in their ministry or department also take part in the policymaking process. The primacy of politics is the reason the political department is the most powerful in any ministry of foreign affairs, and its head, known as “political director,” is typically among the highest-ranking officials.

Waterwheels have been used for centuries for grinding corn, and the first hydro turbine was built almost 200 years ago. Hydro power now produces around 16% of worldwide electrical energy. The hydrological cycle is described and the use of flow duration curves to quantify the resource is demonstrated. The power that can be generated from the hydro resource is calculated, as well as the energy that can be stored in a reservoir. The difference between impulse and reaction turbines is explained with illustrations, and simple approaches to their analysis described. High-, medium- and low-head hydro schemes are described. The use of specific speed to choose the type of turbine for a site is demonstrated. The environmental impact of hydro schemes is discussed. The development of small hydro schemes is addressed as well as the use of Archimedes screw generators. The chapter is supported by 6 examples, 16 questions with answers and full solutions in the accompanying online material. Further reading and online resources are identified.

Wind energy is a major source renewable electricity generation in many countries and the diameter of wind turbine rotors is increasing. Onshore and offshore wind farms are described. The principles of wind turbine operation is explained and the importance of the power curve identified. Wind turbine rotors are analysed using axial momentum theory and the Betz limit; the power and torque coefficients are derived using the axial momentum factor. The generation of torque through lift on the blades is described and the principles of pitch and stall power regulation discussed. Fixed- and variable-speed operation of wind turbine rotors is described and variable-speed operations using two full-power converters demonstrated. Site wind speeds are described in terms of Weibull statistics and the method of bins discussed. The importance of wind turbulence and its effect on turbines is identified. Development of wind farms and the use of measure–correlate–predict to estimate long-term windspeeds is reviewed. The chapter is supported by 3 examples, 14 questions with answers and full solutions in the accompanying online material. Further reading and online resources are identified.

Many renewable energy sources produce electricity, and the fundamental operation of a national alternating current electric power system is described. The difference between real and reactive power is explained. The impact of renewable energy sources on the voltage of the power system is demonstrated through an example and approaches to controlling network voltages are discussed. The control of frequency is described and the importance of maintaining sufficient inertia is highlighted. Scheduling generation in a power system with significant fraction of renewable energy generation is explained. Approaches to demand-side participation and the importance of this concept are discussed. The connection of onshore and offshore wind farms to the power system is discussed. Approaches to the design of PV farms are illustrated. The chapter is supported by 6 examples, 10 questions with answers and full solutions in the accompanying online material. Further reading and online resources are identified.

In Chapter 4, we started with a rigorous derivation of force on a spherical particle in the limit of zero Reynolds number in a time-dependent uniform ambient flow, which led to the BBO equation. We then extended the analysis to spatially varying flows in the Stokes limit and obtained the MRG equation. At finite Reynolds number, due to the introduction of fluid inertia, we saw how difficult a complete solution of the hydrodynamic force on a particle can become. In this chapter, we plan to boldly venture into the difficult topic of interaction between a particle and a turbulent flow.