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For people who can afford new technology. For hundreds of millions to billions of people that's not an option.

Radiative cooling roofs, like those from sky cool systems actually cool your house during the day. I'm not sure how cost effective those are but the technology seems to be very promising.

Those radiate through the atmospheric microwave window, right?

Yep! Looks like the authors of the first paper I read on it (glass microspheres in silver-backed clear plastic film) are finally starting to commercialize it too... http://radi-cool.com/technologies/

Also air conditioning