The production of fuels from renewable sources is one of the most promising alternatives to the current dominant position of fossil fuels in the energy market. Environmental, socio-economic, and geo-political issues make a fast and sustainable transition of high importance. One plausible opportunity for the generation of renewable fuels would be the capture of sunlight and the utilisation of this energy to reduce carbon dioxide, a pollutant, into energy rich molecules, mimicking natural photosynthesis. Here, we describe the challenge and the few successful examples able to produce fuels, exclusively from carbon dioxide, water and sunlight.