The Urban Energy Institute contributes to delivering a carbon-free urban energy system in the Netherlands in 2050. We do this by focusing on innovations along six intertwined themes, covering the building, neighbourhood, district and city scales, and involving multiple disciplines. Theme 1: Towards zero-energy buildings & beyond Theme 2: Fast transition of the existing building stock Theme 3: Thermal urban energy systems Theme 4: Solar Urban Theme 5: Smart monitoring, management & control Theme 6: Transforming the cities