The intersection between energy and the environment is regulated on the basis of legal foundations that international economic law has developed on its own or ‘borrowed’ from (or otherwise relied on) such outside regimes as general international law and international environmental law. The borrowed principles, like sovereignty over natural resources or sustainable development, can find their reflection, directly or indirectly, in trade and investment agreements and case law and will continuously affect new developments in this field. This chapter will show that such foundations stemming from the external sources define the basic contours of State’s rights and duties associated with the energy–environment nexus. Moreover, the international trading and investment systems provide self-created legal foundations for environmental policy space as will also be discussed in this chapter. They define the extent to which energy-related restrictive measures driven by environmental considerations can be accepted. The case of the ECT presented at the end of this chapter is a striking example for demonstrating that the legal foundations are not static and may undergo important changes.

This chapter provides an overview of the different approaches taken by the international community to address liability from environmental harm and how these approaches respond to the unique legal and practical issues associated with areas beyond national jurisdiction. Since liability rules that affect the commons environment exist in both international and national legal systems, the discussion begins with an examination of state responsibility and unharmonized domestic liability, before discussing various approaches to harmonizing civil liability rules through treaties. The discussion of approaches to liability is framed by consideration of the various purposes that liability rules and processes serve in international environmental law.

Chapter 7 explores the further strengthening and consolidation of the international environmental norm as well as contestation around it, from the 1990s until the early twenty-first century. In the first section, I explore how global environmental protection has been further embedded in international policy-making and cooperation. This process involved the inclusion of ever more issues in the international environmental agenda; the insertion of green norms into other international policy areas and regimes, most notably those concerned with economic affairs; and a strengthening and broadening of the institutional architecture for global environmental protection. None of these shifts in international practices and norms were uncontroversial or easy to achieve, they were the result of ongoing battles over how to put environmental stewardship into practice. Indeed, the second section of this chapter will discuss in more detail the ongoing normative contestation over global environmentalism. I conclude the chapter with a review of how environmental stewardship fits in with other primary institutions of global international society.

Because of its transboundary effects and because states will be the primary actors, large-scale solar geoengineering and its governance are matters of international law. This is the first of four chapters that consider rules from custom, treaty, and principles as well as international organizations. Although there are no international instruments that are legally binding, in force, and specific to solar geoengineering, international law provides both a substantial extant governance framework and a foundation upon which future norms, rules, procedures, and institutions specific to solar geoengineering could be built. This chapter introduces how international law operates and discusses several general international legal principles that would guide its interpretation and development with respect to solar geoengineering. It describes one source of binding international law – that of states’ customary behavior – and what it might mean for solar geoengineering, emphasizing procedural obligations. The chapter reviews some relevant nonbinding multilateral environmental agreements and activities of intergovernmental organizations, such as the Intergovernmental Panel on Climate Change.