A single solar panel costs between $120-$315 for the equipment only, or $1,000-$1,200 when professionally installed. System purchases offer dramatic savings: Buying panels as part of a complete solar system costs 40-65% less per panel ($0. 50/watt) compared to individual retail purchases ($0. Your actual cost depends on your home's energy needs, roof characteristics, location and other factors, all of which we'll break down in. Our large solar panel category (200W and up) is designed for modern 24V and 48V systems, offering larger 72-cell panels for maximum output or 60-cell panels for easier handling. Why Choose Us? More Power, Same Space: Advanced technology delivers higher efficiency. High-Efficiency Solutions: Modern. When you're determining your solar power needs, you have to consider three factors primarily: how much energy you generally use per month, the percentage of that you'd like to offset with solar and where you live, which determines how much sun your panels can harvest. The average cost per watt ranges from $2. 50, translating to $12,500 to $17,500 for a 5-kilowatt system.