We have seen renewed pledges of investment in renewable energy, including hydropower, as well as nuclear energy at COP28 and COP29, although progress varies considerably, as per International Energy Agency reports. In the lead-up to COP30, calls to accelerate the energy transition and honour these commitments are intensifying. In this context, Lucy Goodman and Christopher Schulz highlight surprising parallels between large-scale hydropower and nuclear energy infrastructure, sounding a note of caution about their planned expansion in many countries around the world.