At this year's ACHEMA, there was no independent exhibition or thematic area on energy, nevertheless, energy played a major role again. Heat was an important topic. Here, a focus was on waste heat utilization to improve energy efficiency, but also new developments could be found in the field of combustion technology. In addition, innovations in conversion of electrical energy into heat or into fuels or basic chemicals were presented. Hydrogen and biomass-based technologies also played a major role.