The necessary CO2 would be captured from fossil fuel burning power plants and other industrial flue gases including cement factories. With diminishing fossil fuel resources and therefore CO2 emissions, the CO2 content in the air could also be used. Considering the low concentration of CO2 in air (0.04%) improved and economically viable technologies to absorb CO2 will have to be developed. For this reason, extraction of CO2 from water could be more feasible due to its higher concentrations in dissolved form. This would allow the chemical recycling of CO2, thus mimicking nature’s photosynthesis.