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.
Two projects are done. Designed and bought my YouTube logo bumper sticker.
Do not clean your solar panels with abrasive chemicals. You should use some lukewarm water, a soft cloth and some biodegradable soap if needed. Clean your panels at least once a month or more frequently if you notice your green energy system is not producing as much power as it should.