Use winter sunshine hours instead of summer hours whenever you are calculating how many solar panels you will need. This is because winter sunshine hours only add up to about half that of summer. It is better to overestimate how many panels you will need rather than underestimate. If you underestimate, you will end up losing power when you need it.
Before signing any agreement for installation of solar energy products, get at least three estimates. Once the estimates are in your hand, read each one carefully to ensure that the installation is up to your standards. Each estimate should include a time frame of completion, a list of materials and the estimated amount of labor charged.
Before making a choice on how many solar panels you use make a list of all the electrical appliances you use and the wattage and hours utilized by each one. This will be helpful in determining how much solar power you will need. No matter if you decide to install the equipment yourself or have someone else do it, this information will help your choices.