The Absence of International Renewable Energy ‘Hard Law’
By: Sophie Bacas
In the months preceding COP30, the ICJ delivered its Advisory Opinion affirming that international law requires all States to prevent significant environmental harm, and that the environment must be protected for present and future generations. Law creates and maintains an architecture for realizing common needs and satisfying societal aspirations. International law shoulders the heaviest burdens, as it functions to achieve international solutions for global problems and lays the groundwork to satisfy aspirations for a better world. The solutions provided by international law are imposed on sovereign nation-states who provide their consent—for example, by agreeing to the terms of a treaty or recognizing a principle of international law. In doing so, States limit their sovereignty but open themselves to collaboration and development. Such progress is only heralded by “hard” international law and merely encouraged by “soft” international law.
While treaties and customary international law are hard law, yielding legally enforceable obligations and imposing sanctions for noncompliance, soft law—such as agreements and declarations—dominates the international stage, as it provides guidance and influence without authority. Soft international law has therefore become the predominant mechanism for discourse regarding global climate change redress, including matters concerning renewable energy. As the world barrels toward a warming limit of 2°C above pre-industrial levels, alternative energy sources are increasingly necessary in lieu of energy produced by the combustion of finite fossil fuels. Despite this reality, hard law solutions on renewable energy are notably lacking on the international stage; however, alternative agreements and pledges may pave the way for binding solutions soon. These binding agreements could arise from the mandates set forth by the ICJ, which clarified that States’ obligations under international law not only encompass those set forth in climate treaties but also extends to customary international law duties to prevent significant harm to the environment.
In December 2023, 118 States pledged to increase the global renewable energy capacity and increase the annual rate of energy efficiency improvements by 2030. The Global Renewables and Energy Efficiency Pledge (“COP 28 Pledge”) marked an important step in accomplishing the objective of the 2015 Paris Agreement, which aimed to limit global warming below 1.5°C. Specifically, the COP28 Pledge sought to triple the world’s renewable energy capacity to 11 TW by 2030 and double the average annual rate of energy efficiency improvements every year until 2030. While the COP28 Pledge was a groundbreaking achievement in collectively acknowledging that increased renewable energy use and production are necessary in a warming world, these goals are not grounded in legal authority. Sanctions and consequences are absent from the COP28 Pledge’s language, providing no provisions for holding signatory States accountable if they fail to meet their goals. Additionally, for the stated goals of the COP28 Pledge to yield tangible results, national policies are required for implementation. To date, national policy implementation for renewable energy transitions would only be achieved through the voluntary action of signatory States, with no recourse for failure. Time will tell how the ICJ Advisory Opinion will impact that potential recourse.
The singularity of the COP28 Pledge and its lack of legal consequence highlight a greater absence in the field of international environmental law. Following the 1972 United Nations Conference on the Human Environment in Stockholm—the first world conference on the environment— landmark conferences on global sustainable development have produced binding treaties and customary international law compelling States and international actors to reduce air and water pollution, preserve wildlife and biodiversity, protect oceans, manage hazardous waste safely and effectively, and limit ozone depletion, among other goals. However, a mandatory transition away from fossil fuels and toward renewable energy—for the purposes of limiting air pollution, providing safe and effective energy to States, and mitigating global climate change—is lacking from this list, despite offering a tangible solution for a shared problem. Many States, such as Sweden, Costa Rica, and the United Kingdom, have already transformed their energy systems to rely on renewables; however, international law mandating renewable energy transitions has failed to materialize.
While the doctrine of stare decisis does not apply to international law, previous covenants have emphasized the necessity of renewable energy development and installation. For example, the 1992 United Nations Conference on Environment and Development and the subsequent adoption of the United Nations Framework Convention on Climate Change (“UNFCCC”) highlighted the importance of renewable energy adoption in combating climate change. Similar major agreements include the Kyoto Protocol, advocating for increased renewable energy use in Article 2; the Paris Agreement, encouraging sustainable development and greenhouse gas reduction; and the formation of the International Renewable Energy Agency (IRENA), supporting the transition to a sustainable future by promoting the adoption of new forms of renewable energy. However, current hard law does not establish an international renewable energy agreement. Energy is a crucial staple of modern life and technology—necessary for everything from transportation to education to health and innovation—yet cleaner and more sustainable pathways for its production have not been codified within binding international law. This absence must be addressed, and it is for this reason that a binding international agreement calling for increased capacity, development, and installation of renewable energy is urgently needed.
This article was written by PECC's Energy and Climate Law Scholar Sophie Bacas, a law student at Elisabeth Haub School of Law at Pace University. It was originally published on November 10, 2025, in Volume 1, Issue 2 of the R.E.A.C.T. by PECC Newsletter.
Editors: Mercè Martí I Exposito, Frances Gothard, Carington Lowe