Not impossible. The limit is cooling air flow. If you blew air through a 4m x 4m radiator at 30 m/s, 43 megawatts would generate a 68 C temperature rise. Those

Not impossible. The limit is cooling air flow. If you blew air through a 4m x 4m radiator at 30 m/s, 43 megawatts would generate a 68 C temperature rise. Those sort of energy densities aren't strange. A hair dryer dissipates 1000 watts in, say, 10 x 8 x 6 cm. So a cube of hair dryers 2.7 meters on a side generates about 43 megawatts.