I'm starting my first grow: 3x3 feet tent 300watt LED (100watt actual draw) Right now my tent with lights on and passive ventilation only is about 66F and that's with it being warm outside (40F). The room will very easily get to high 50s at night. I still haven't added active ventilation but image that it will severely decrease the temperature in the tent. I figured I could use some Incandescent bulbs for heat. since they are 90% infrared they should heat up the plant but not the air as much as a normal space heater would, thereby saving electricity. What are the pros and cons of using Incandescents vs a small space heater. I'm not too concerned with it getting too hot, since I'm using LEDs at a relatively low wattage.
Can you not get your intake air from a heated indoor space? If you can it may be worth ducting it in. High 50's isn't a problem. Mine drop to 59-58 and don't seem to be effected. You don't want to go any colder than that though if you can help it. For one thing that is not enough wattage for a 3x3. You need about 3 times the actual watt power to get any kind of decent yield from that 3x3. That's one reason your tent isn't warm enough. You don't have enough light. If you must add heat I like those chicken coup heaters. Many are pretty rugged and waterproof. They're way lower power then most heaters too so they won't up your electric bill much. When you have a grow room that needs heat the best option is usually to add more light. That will take care of your heat problem and since you're running 100 watts in a 3x3 you really will need it. 600 watts is typical for a 3x3 BTW for flower.
The room is just an unused room that we currently aren't heating. I could just turn the heat on in the room. Which might be cheaper than use electric heat. We have propane and an HVAC system. I was only planning on growing 1 or 2 plants and get hopefully 3 or 4 ounces every few months. Is that reasonable, or do you think I would still need more wattage. What if I just hung 4 or so CFLs? That way I can get some extra heat and some extra light.
4 quality CFL's are getting in the price range of buying a lower price range LED panel like the Mars300 on ebay. I've seen them for $69 and they can certainly outperform 4 CFL's. Just do that and double your lighting because 100 watts is micro grow range and only 1 plant max. You have the area and more light isn't expensive, weed is.