The number of solar panels needed for a house is not based solely on size, so no two 1000 square feet homes will be entirely alike. It’s easier to determine your solar panel needs based on your monthly electric bill cost and location.
General guidelines recommend that homeowners install at least a 5-kilowatt system for a 1,000 square foot house with an average electric bill of $50-60 per month. The average cost per watt in the U.S. is $3, so a 5,000-watt solar power system would cost approximately $15,000. This does not account for important factors such as your specific location (and weather), roof orientation, type of house and available state and federal incentives and grants.