TECHNOLOGY FOCUS - CHEMICAL ENGINEERING - Preferred System: The methane/methanol producing system further comprises a wavelength adjusting member provided in a laser beam transmission path for converting or shifting the wavelength of the laser beams. The laser generating device comprises a sunlight-excited solid laser which comprises a condensing lens for condensing sunlight at high density and at least one elongated laser rods arranged in parallel at predetermined spacings, optical resonators comprising reflecting mirrors provided at both ends of each laser rod, a light reflecting member surrounding each laser rod, and sunlight condensed by the condensing mirror irradiated on each laser rod or passed several times through the laser rod by reflecting by the reflecting mirror, thus generating radial light in the laser rods by the action of the laser activating substance by amplifying and oscillating the radiant light using the optical resonator. The light reflecting member comprises a clad portion that is different in reflectance from the laser rod. The laser rods are buried in the clad portion. The light reflecting member comprises a reflective surface having a coating of a high reflectance and provided on the inner surface of a hollow cavity. A clad layer is provided on the outer periphery of each laser rod in the hollow cavity to adjust the refractive index of the laser rod.An aspect ratio which is a ratio of the diameter to length of the laser rods is at least a predetermined value to suppress the diverging angle of laser beams to transmit them such that diversion of the laser beams transmitted to a light-receiving facility on the earth will be less than 100 m. Each laser rod is formed of a laser medium having the maximum absorbing property within the peak wavelength of the optical energy density of sunlight or within a predetermined range. The laser medium comprises at least one kind of laser activating substance having the maximum absorbing properties within the peak wavelength of the optical energy density of sunlight or within a predetermined range.