I came across this company and am intrigued. They improve the efficiency of cooling systems with radiative cooling panels. Home - SkyCool Systems I hope they do well.
Wow! That does look cool (ahem) and I have all that north-facing roof left over. They don't seem ready to sell panels today, but perhaps at the next house. I only run the AC at this house about twice a year here next to the water.
They have updated their FAQ page and under a question about residential they have added an option to sign up for future updates.