3 tons

NV.

Senior Member

Joined: 03/13/2009

View Profile

Offline
|
100w panel in ideal test conditions likely to put out just over 5.x amps, but in the vagaries of the real world subtract about 1/3 (say, for an average) and an 18v panel output is likely a bit too high for the fan…
3 tons
|
wanderingaimlessly

Maryville Tn

Senior Member

Joined: 08/23/2017

View Profile

Offline
|
For a greenhouse application, you should not need 24/7 operation.
A small battery (rv/marine group 24) and some sort of timer to turn the fan off and on several times a day could work. You may end up looking at a small 300 watt inverter and a 120 Volt timer to put it together.
|
red31

Dallas

Senior Member

Joined: 08/04/2008

View Profile

Offline
|
both the panel and motor should have the same resistance @ ~ 10v
|
2112

Texas

Senior Member

Joined: 07/16/2011

View Profile

Offline
|
I vote for hook it up and try it. You won't harm the panel. If it's an automotive radiator fan they are rugged. You may not get to full speed but see what you do get.
The fan is a big inductive load so placing a diode on the positive output of the panel may not be a bad idea. Plus the diode will lower the voltage a bit.
Come back and let us know how it worked out
2011 Ford F-150 EcoBoost SuperCab Max Tow, 2084# Payload, 11,300# Tow,
Timbrens, PullRite SuperGlide 2700 15K
2013 KZ Durango 2857
|
2112

Texas

Senior Member

Joined: 07/16/2011

View Profile

Offline
|
Very informative video series.
OP - This is worth watching. Part 3 drives it home.
Maybe something like This Buck Converter would help.
The panel may not be able to provide enough in-rush current to start the fan on its own. Maybe it will, maybe it won't.
You may need to connect a capacitor on the converter input with the converter turned off. Let the cap charge up then turn the converter on to kick start the fan.
* This post was
edited 04/29/22 05:16am by 2112 *
|
|
austinjenna

Columbus, Ohio

Senior Member

Joined: 03/27/2002

View Profile


Good Sam RV Club Member
Offline
|
I have a 5 0r 10W panel connected to an on/off switch and then to a fan mounted in the ceiling vent of my fiver in reverse to suck the hot air out in summer. Its been working for the last few years without an issue so it can be done. Naturally the fan speed will be variable depending on how much sun is hitting the panel
2010 F350 CC Lariat 4x4 Short Bed
2011 Crusader 298BDS 5th Wheel
Reese 16K
|
tarnold

georgia

Senior Member

Joined: 03/01/2010

View Profile

Offline
|
Op here. Ok, ordered a renogy mppt controller. As much $ as the panel. Had asked the question to renogy yesterday afternoon, got an email from them at 2:20 AM! Somebody works late, or another country.
|
Lwiddis

Southern California :(

Senior Member

Joined: 08/12/2016

View Profile


Good Sam RV Club Member
Offline
|
Least expensive MPPT from Renogy I see is $85. Good for up to three 100 watt panels.
Winnebago 2101DS TT & 2022 Chevy Silverado 1500 LTZ Z71, WindyNation 300 watt solar-Lossigy 200 AH Lithium battery. Prefer boondocking, USFS, COE, BLM, NPS, TVA, state camps. Bicyclist. 14 yr. Army -11B40 then 11A - (MOS 1542 & 1560) IOBC & IOAC grad
|
ewarnerusa

Helena, Montana

Senior Member

Joined: 12/20/2011

View Profile

Offline
|
Sounds like a nice controller, but now you'll need a battery. In fact, many controllers will be damaged if you hook solar input to them without having it hooked to a battery.
I'm not sure why someone said it needed to be an MPPT, we're talking a single 100 W 12V panel here. I'm not saying MPPT can't provide more than PWM, but on a small scale like this it is not something worth paying for.
Some controllers do have a "load" output which would do what you're trying with the fan. But I think would still need a battery.
Aspen Trail 2710BH | 280 watts of solar | 2x 6V GC batteries | 100% LED lighting | 1500W PSW inverter | MicroAir on air con | Yamaha 2400 gen
|
valhalla360

No paticular place.

Senior Member

Joined: 08/19/2009

View Profile


Good Sam RV Club Member
|
If the controller does require a battery, you also will need a timer.
If you put a battery in and the fan runs when there is voltage from the battery, the battery will tend to run down at night. Might last a few weeks but constantly running the battery to 0% charge will kill the battery very quickly.
Tammy & Mike
Ford F250 V10
2021 Gray Wolf
Gemini Catamaran 34'
Full Time spliting time between boat and RV
|
|