1. United Nations (2020) Sustainable Development Goals, https://www.un.org/sustainabledevelopment/sustainable-development-goals/20200. Accessed 20 Jan 2020
2. Treaty of Lisbon amending the Treaty on European Union and the Treaty establishing the European Community, signed at Lisbon, 13 December 2007. European Union 2007
3. International Energy Agency (IEA) (2018) World Energy Outlook
4. Strategic Energy Technologies Information System (2018) The Strategic Energy Technology (SET) Plan. At the heart of Energy Research & Innovation in Europe, https://setis.ec.europa.eu/strategic-energy-technology-set-plan-heart-of-energy-research-innovation-europe. Accessed 9 June 2020
5. Directive 2012/27/EU of the European Parliament and of the Council on Energy Efficiency Amending Directives 2009/125/EC and 2010/30/EU and Repealing Directives 2004/8/EC and 2006/32/EC. Official Journal of the European Union 14/11/2012; OJ L315:1, 25 Oct 2012