A neighbour had his roof re-shingled and they changed the black 'whirlybird' roof vents to brown to match his new shingles.
I scooped all 3, two went on my garage, the other I put on top of a little plywood box I built just big enough to drop down over a MaxAir vent cover.
When parked for any length of time I drop the unit over one roof vent and leave the other wide open.
On a warm day even if the air is dead still that vent spins around pretty good and you can feel the air moving from the inside.
Zero power consumption, zero cost.
