In industrial process and during our most common daily activities, vast amounts of energy is lost in the form of low-grade heat. In Flanders, Belgium, the heat wasted to the atmosphere by the chemical industry is estimated at 4.9 TWh/y (2015). This astonishingly represents circa 10% of the yearly energy production by Belgian nuclear power plants. H2E aims to innovate heat-to-electricity conversion, unlocking the valorisation potential of low-grade residual heat. Heat-to-power conversion can be achieved by thermoelectric generators (TEGs), devices that exploit the Seebeck effect to build up an electric potential across a stack of semiconductors subjected to a temperature difference. This physical effect has long been known, but widespread application has remained limited because of the low efficiency (less than 5%) and high cost of available semiconductors, often containing rare metals and featuring high toxicity and poor thermal stability. Using less expensive semiconductor materials and increasing efficiency are the main challenges to broaden the application field of TEGs. H2E proposes a new approach to enable improved TEGs using a thermo-electrochemical-hydrogen production device (TEC-H) based on recently discovered, robust, low cost, non-toxic porous semiconductor materials. These new semiconductors are implemented in an original design, mounting them in stacks to produce a TEC-H device that is modular and exhibits good scalability. H2E will enable valorisation of low-grade waste heat in the temperature range below 100 °C, a range currently not exploited in industry. Besides industrial waste heat, also low-grade geothermal heat represents huge potential. In this way H2E will contribute to a more energy-efficient and low-carbon future, in line with Europe’s long-term strategy to become climate-neutral by 2050 as set by the European Commission in The European Green Deal.
