Will this save money and coal, considering that I'll probably have to use fans more?
You will save a lot of electricity by using fans instead of air conditioning.
Generally speaking, you would need to run 10 or more fans at a time to use the same amount of electricity as a small air conditioner. This applies to the relatively large (20 inch) household fans - smaller fans use less power but I wouldn't recommend them because they won't do as much for your comfort.
If it is cooler outside than in, I recommend having a fan in the window pushing cool air in. If you want to, you should then have another fan pointed at yourself.
If you wear a damp towel on your shoulders and back, it can cool you off too.