Residential Solar Planning with SolarScope
SolarScope helps homeowners and solar installers evaluate rooftop solar potential quickly and accurately. A residential solar analysis tells you how much energy a system can produce at your home, what size system makes sense, and what return on investment you can expect — all before spending a dollar on equipment.
Homeowners use SolarScope to validate installer proposals, compare system sizes, and understand what drives solar production at their specific location. Installers use it for rapid pre-sales analysis that they can share directly with prospects.
Step 1: Assess Your Location's Solar Resource
The first step in any residential analysis is understanding the solar resource at your address. In SolarScope, create a new project with your home's address. The analysis returns:
- Annual GHI: The total solar radiation available at your location. US residential sites range from about 1,200 kWh/m²/year in the Pacific Northwest to over 2,100 kWh/m²/year in Arizona.
- Peak Sun Hours: The daily average of full-sun equivalent hours. 4.5–6.5 PSH is typical for most US residential markets.
- Monthly distribution: How solar production varies by season at your latitude.
A site with 5.5 peak sun hours receives about 22% more solar energy than a site with 4.5 peak sun hours — this directly impacts system sizing and payback period.
Step 2: Determine System Size
The right system size depends on your electricity consumption, roof area, and financial goals. Use SolarScope's analysis to calculate how much a given system size produces:
Basic sizing formula:
- Annual consumption (kWh) ÷ Peak Sun Hours ÷ 365 ÷ System Efficiency = Required System Size (kW)
For a home using 12,000 kWh/year in a location with 5.0 PSH and assuming 80% system efficiency:
12,000 ÷ 5.0 ÷ 365 ÷ 0.80 = 8.2 kW DC
Create multiple projects in SolarScope with different system sizes to compare annual production estimates and find the size that offsets your target percentage of electricity use.
Step 3: Evaluate Roof Suitability
Use Site Studio to open your home address on the satellite map. Identify usable roof sections:
- South-facing sections are optimal in the northern hemisphere (azimuth ≈ 180°)
- East and west-facing sections produce 15–20% less than south-facing arrays but are viable when south roof area is limited
- Flat sections can be mounted at optimal tilt angles
Identify shading obstacles: mature trees, chimneys, dormers, adjacent structures. Shading can reduce production by 10–30% for affected strings.
Step 4: Calculate Estimated Return on Investment
With your production estimate from SolarScope, calculate a simplified payback analysis:
- System cost: Get quotes from licensed installers (average US residential: $2.50–$3.50/W installed)
- Annual savings: Annual production (kWh) × your utility retail rate ($/kWh)
- Tax incentives: Federal Investment Tax Credit (ITC) is 30% of system cost through 2032; check state incentives
- Simple payback: (System cost − Incentives) ÷ Annual savings
A well-sited 10 kW system at $3/W in a market with $0.15/kWh and 30% ITC typically pays back in 7–10 years with 25-year system life.
Using the AI Assistant for Residential Analysis
The SolarScope AI Assistant can answer specific questions about your residential analysis:
- "Based on my 5.2 PSH and 12,000 kWh/year usage, what system size do I need?"
- "My installer quoted a 10 kW system — does my roof get enough sun to justify that?"
- "Should I add battery storage based on my production profile?"
Share your project data with the AI assistant for personalized recommendations.