Some factors to csiendor:-Place your solar cells at the best angle for the current season to optimize your exposure to solar energy.-You can have an  off-grid  or  on-grid  system, Off the grid you are going to be storing your power in batteries, with a circuit designed to best charge your batteries for different changes in weather i.e. cloudy days, low sunlight conditions.You will also need to look into power inverters to take that DC battery power and transform it 120V AC (U.S.)-An  on-grid  system will send your power directly into the grid of your utility company.  Instead of producing your own power you will be paid for the energy you supply to the grid.-5 KWh = 5000 W * hHow many hours of sunlight do you average per day?5000 / hours of sun = the wattage your solar power plant needs to produce.i.e. 5000/6 = 833.3 Watt system needed.