Powered attic ventilators cause more problems than they solve so if solar powered models have gone up in power that makes them less desirable than ever not more desirable.
Solar powered attic fans do they work.
Whether or not an attic fan really works is a controversial subject.
Fans slow down or stop when most needed.
Do attic ventilators effect the home s temperature.
Energy professionals will tell you that they do more harm than good.
Manufacturers of attic fans as well as hvac companies will tell you otherwise.
I saw an advertisement for a solar powered attic fan and that seems like a great.
In general it s widely believed that an unpowered attic ventilation system will result in a cooler home.
So while solar powered units may not be plugged into your home s electrical system they are still pulling up cooled air once again forcing the a c unit to work harder.
Ad the infrared rays from the sun are powerful.
But there s really a more fundamental reason that power attic ventilators won t help a lot and for some reason i didn t mention that in the original article.
According to the home ventilating institute hvi powered attic ventilators need to move a minimum of 700 cubic feet per minute cfm for 1 000 sq.
The solar attic fans all moved less than 1 000 cubic feet of air per minute cfm and they did nothing to lower the temperature inside my own attic.
And it s part of the reason that my state georgia has banned power attic ventilators unless they re solar powered which was a concession needed to get the grid powered fans banned.
My attic space gets as hot as blue blazes.
Solar powered attic vent fans usually don t move as many cubic feet of air per minute cfm as hardwired fans.
Ft of attic space for example 20 x 50 to be effective.
Fans don t move lots of air.
There may never be an roi.
But after seeing my solar powered attic fan work i have a long list of cons solar powered attic fan checklist.
You will probably need two solar attic fans to get the results you want.
Because solar attic fans operate with a lower power output they are unable to move as much air as some of the other options that are available.
That means you will need to double up your investment in this area.
Danny s tests of solar attic fans showed that in florida where there s abundant solar energy yearly savings from installing two fans in a house with just over 1 000 square feet of air conditioned floor area amounted to only 460 kwh.
Many are solar powered and require no other wiring so they don t cause any additional charges on your electricity bill at all.
Most ceilings are leaky.
But they re much easier to install since no wiring is needed.
Depending on what your utility charges that s about 40 per year.
The beneficial effects of solar powered attic fans if any are limited to a subset of houses those with airtight ceilings.