You should assess how much energy you need for your household before investing in a solar energy system. You will get the most out of your solar energy system if it is powerful enough to cover all your energy needs and allows you to sell a small quantity of power to the main grid.
Always use non abrasive cleansers on your solar panels. An abrasive cleaner can scratch the surface of the panel and cause permanent damage and affect how well the solar panel works. There are commercial cleaning solutions to use or you can use a pool skimmer with a very soft cloth on it.