If you have a pool, don't even think of heating it any other way than solar! This is easily the most efficient use of solar power there is and it will save you a bundle. Solar heating systems cost about the same or less than conventional systems and basically operate themselves so stop wasting your money doing it the old-fashioned way!
Track numbers when getting solar panels for the home. Solar panels might not be a good option if you cannot count on optimal exposure to sun rays in your area or if you use more power than a regular solar energy system can generate. You need to do all your homework, so you know if this type of energy is really going to save you money.
UPDATE: When not in direct sunlight, it can take forever to charge. Be patient if you buy this. 19 bucks last I checked on Amazon: https://amzn.to/2mFFJS4 …
A solar powered fan for your attic is a good choice if switching completely to solar power is not feasible. The fan will have a temperature sensitive gauge and switch itself on when necessary. This will remove heat and lower the cost of cooling. It's also solar powered, so you don't have to pay to power it.