Solar energy is one of the most abundant sources of renewable energy. The utilization of solar energy and CO2 in the atmosphere to generate fuels is regarded as a great way to resolve both the problems of fossil fuel depletion and global warming. An artificial tree was constructed to generate polymer fuels from water and CO2 in the atmosphere. Solar panels acted as leaves to absorb solar energy and generate electric energy, and the CO2 in the air was absorbed by alkalized water and then converted to polymer fuels in an electrolytic cell. This tree yielded an energy efficiency of 53.3% for the generation of polymer fuels, and the ratio between the combustion heat of the polymers and the electric energy consumption was 701.6%. Additionally, the energy conversions in the process of polymer generation were investigated, and the evidences of radicals generated from water by electric field induction were provided. The results provide an alternative method to utilize solar energy.