Because an awful lot of them don't have it.
U.S. households use more energy for A/C than the rest of the world combined. But that's changing, fast.
This is way more unbearable than standing on black asphalt in the blazing sun.
The makers of the grass-covered "Babilawn" claim it makes ugly A/C units "aesthetically pleasing" from both "inside and out."
New research suggests that Minneapolis actually uses way more energy staying warm in the winter than Miami does keeping cool.
One less thing to worry about as your face melts off during today's record-breaking heat wave.
U.S. cities in the South have their own set of challenges to face in going green. But Atlanta, for one, is trying.