Exhaust Fan Temp Control

I have an S&P TD-100 for my exhaust in a 4x4. Temps too low in winter, especially night temps.

I have considered buying a hyper fan 6" but but if you really want the temperature control you have to spend $240. I've already spend money on my current fan that I up till now have liked.

I'm just trying to have it not work so much at night, which is why the day/night controllers look so attractive to me.

I have looked at the spartan series fan and cooling controllers and because I have no experience I don't know if either one would do what I want. I want Day tempt 77-80 and night temps 70-72.

These damn controllers are more than the fan was.

I have also read things saying even if you control the fan's RPM the fan still sucks up the same original wattage.

I just want to buy a controller that will lower my fan's RPM while also using less watts instead of dissipating it as heat.

I am running DIY Led Cob lights at 225 watts for now.

I have considered lights on during the night and lights off during the day but I'm not going to do that. I want fan/temp control.

Thanks

Lights off in day time and on in night time is standard where I live, makes sense.
I have just bought a variac speed controller to stop the hum that the little speed controlled ones create when fan speed is not lowered but shifted on/off/on/off so many times a second. Anyway in my search for the right one I read a post claiming that S&P fans should not be used with a speed controller. The dude said he had seen it on the S&P website, I would contact S&P directly to ask them about it. Because you don't want to waste money for a start and the info I came across was second hand info, possibly BS.

S&P makes speed controllers, they call them "Continuous Ventilation Control." The one for for the TD100x is "CVC-100X" and it cost me $29. It cuts the power in half, so high/low is 32/16W without and 16/8W with the controller.

Another option is to just use a timer and only run fan occasionally during lights out. That is what i do. Runs whole time the lights are on, then about every 1.5 hours it goes on for just a couple of min to keep humidity down.
Cost about $12 for the digital timer.
Just my .02
WE