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.
If the cost of solar panels is prohibitive, you might consider buying one at a time. An energy audit can be requested from your electric company. This will assist you in figuring out how you use energy, so you could make some adjustments. This will allow you to use fewer solar panels.