Application for 100W panel

[littleharbor]

Using two fans was the key to my speed control. A single fan rated at 80 watts was just screaming with a 65 watt panel.

[solardreamer]

Using two fans was the key to my speed control. A single fan rated at 80 watts was just screaming with a 65 watt panel.

Glad it worked out well for you. I think we may be using similar 80W 12V radiator fan. Are you fans pusher or puller fans?

I had thought about using 2 fans but I didn't really have the room and even the 1 fan was already loud enough since it's my house attic so I decided not to use 2 fans. Instead, as I mentioned earlier poss, I am using a DC-DC converter with battery and it has worked well for almost 2 years now. In general, peak attic temperature lags peak sun so I have found my setup gets the attic cooler faster than only direct connection from fan to panel which tends to slow down too much when attic temperature is still very high.

[littleharbor]

This is what I used, sourced from ebay12 volt radiator fan.jpg Says push/pull by removing and flipping the fan. They come in a variety of sizes something like 7" to 16"

[solardreamer]

This is what I used, sourced from ebay12 volt radiator fan.jpg Says push/pull by removing and flipping the fan. They come in a variety of sizes something like 7" to 16"

That's what I ended up using after the 20W fan burned out. I use it as a pusher to be consistent with all the attic fans I have seen. Just wondering if anyone tried it as a puller in attic.