Solar Powered Fan

[Sarge]

I'm into all things solar powered. I've got 3 KW of solar panels on the ole homestead and love to find ways to get the sun to power 'toys.'

One situation I came across was venting my trailer while I'm out hiking or doing other stuff. I'm completely incapable of hammering a nail straight, wouldn't dream of working on my car or anything else mechanical, and leave electrical items to the professionals...but I have successfully set up a solar powered fan that works great on my teardrop.

Quick background - the solar-panels on my home connect to the grid via a SunnyBoy 2500 inverter (converts DC to AC). SMA, who makes the SunnyBoy, suggests that you install the SunnyBoy on the north side of the exterior of your home if you live in the Northern Hemisphere. This way, the heat sink that sits on top of the SunnyBoy can have airflow but not be in direct sunlight. I couldn't install it that way, so my SunnyBoy sits on the east side of my house and gets direct sunlight for a few hours a day. When this happens, the SunnyBoy begins to heat up more than the heat sink can dissapate, so it starts 'derating' or scaling down the energy flow through the inverter. One ingenious way to keep the inverter cool is to force air flow through the heat sink. In my case I accomplish this by using a 12 volt DC fan, the kind you would use in a desktop computer, hooked up to a 4 watt DC solar panel and placing the fan on top of the heat sink (using the metal guard screen on the fan to keep the platic off of the metal heat sink). It works wonderfully!

For my teardrop, I just duplicated the setup, but with a larger (5 ", 97 cfm) fan that I bought at FRY's, a local electronics warehouse store. The 5" fan snugly fits between the open teardrop door window and the window frame. I then rest the solar panel on the roof. Now, while I'm away from the trailer, the system circulates air through the cabin drying out condensation and replacing hot trapped air with slightly cooler fresh air.

To get an idea of what I'm talking about, check out this link: http://www.crystalbay.net/solarhousefan/solar-fans.html

-Sarge