Due to humid weather, I have to install a dehumidifier in my crawlspace to keep the humidity under control. This means I also need to seal off the crawlspace vents. But I want a little bit of air movement to prevent stagant air in the crawlspace. So I leave one foundation vent unsealed and put an exhaust fan there and set it to low power. The makeup air comes from leakages in the crawlspace and could come from outside or the living area.
The exhaust fan inevitably expells some air that has been dried and heated by the dehumidifier, thus wasting energy. Ideally, only un-dried air is exhausted by the fan.
To reduce wastage, I put the dehumidifier at one end of the crawlspace and the exhaust fan at the other end. The exhaust fan intake duct is place near the ground where the air is cooler.
Are there other ways to further reduce energy waste?