AbstractThis paper presents the further development of the concept of an FEL-based driver for a commercial inertial confinement fusion reactor. We have shown that it is technically feasible to construct a laser system with the following parameters: laser light wavelength 0.5 μm, flash energy 4 MJ, repetition rate 10 pps and net efficiency 10%. It becomes possible due to the use of a novel scheme of optical power summation.