In 2015, 196 countries pledged to work together to combat climate change. The Paris Agreements, initiated in 2016, sought to limit the increase in global temperature by the end of this century to 1.5 • C above pre-industrial levels. To meet this goal requires significant changes to how we generate and consume energy: by 2030, 30% of global energy must come from renewable sources, and the efficiency with which energy is used must improve by 32.5%. A 2017 report by the International Energy Agency identified key areas of improvement for each of the major signatories to the Paris Agreements, and outlined a "Bridge Scenario" in which improved energy efficiency could account for a 48% reduction in global emissions by 2030. The building, industry and housing sectors alone have the potential to contribute ca. 20.7% of this reduction. While intensive research has led to rapid improvements in primary energy-generation technologies such as photovoltaics and supporting technologies such as batteries and grid-level storage, technologies aimed at enhancing energy efficiency have re-ceived less attention. Given that an estimated 60% of the energy used globally is wasted as heat, a strong contender in this area are thermoelectric generators (TEGs) to recover waste heat as electrical energy. (The dual function of solid-state cooling also has a number of important contemporary applications. ) TEGs are solid-state devices with no moving parts, allowing for maintenance-free operation, and have proven reliability in the aerospace industry. They have also been proposed for, among other things, powering wireless sensors, recovering waste heat from household chimneys, and improving the efficiency of combustion engines. The performance of a thermoelectric material is often measured through the dimensionless figure of merit ZT :