We did this. This is nearly 5 W per m2 of primary. Other solar lasers have used 33.5 m2 to produce 60 W and 78 m2 to create 18 W. As one notices, their efficiencies are at least 3 times less than ours. Besides the power measurement, we found that solar lasers have additional problems not seen in commercial lasers. The resonator stability depends on how well the sun is tracked.
Clouds decrease the heating in the laser rod and cause the focal length to shift severely.
Heliostat tracking displacements move the center of the absorption distribution inside the laser crystal. If the center of the thermal lensing moves, it acts as a resonator misalignment and less output is obtained. Future research will require more attention to keeping the laser stable with respect to the misalignment in heliostat tracking. Clouds are unavoidable. Using a resonator than ios more stable to a wide range of thermal focal lengths will give more consistent lasing.