"Such novel technology is often based on coating materials that reflect solar energy in visible near-infrared wavelength range (0.3–2.5 μm) and send infrared heat to the universe through atmospheric transparency window". https://www.sciencedirect.com/science/article/abs/pii/S00323...
Any other benefit including solar water heating or photovoltaic generation is just burying the lede. 60We/m2 is just fine if it is sharing space with other applications. The fact that they are achieving this with basically doped silicone caulking rather than something like indium tin oxide is fantastic news. Dumping heat into space rather than our oceans and atmosphere is going to matter a whole lot more in the near future, and it even works when it is cloudy.