Step 1: Select Your Location
Start by selecting your city and state. Our calculator uses PVGIS data specific to your location's coordinates, accounting for local solar irradiance patterns.
Why Location Matters
- ✓ Solar irradiance varies significantly by location (Arizona vs. Maine)
- ✓ PVGIS provides accurate data for 1,300+ US cities
- ✓ State-specific regulations and incentives are automatically applied
Step 2: Enter System Details
System Power (W)
Enter your total system capacity: 400W, 600W, or 800W are most common for balcony systems.
Tip: 800W = 4 × 200W panels, 400W = 2 × 200W panels
Orientation & Tilt
Select panel direction (South, East, West) and tilt angle (0-45°). South-facing at 20-30° is optimal.
Tip: Use a compass app to find your exact direction
Step 3: Financial Parameters
Electricity Price ($/kWh)
Check your utility bill for current rate. National average is $0.13/kWh, but ranges from $0.10-$0.30/kWh.
Where to find: Look for "Price per kWh" on your monthly electricity bill
System Cost ($)
Total investment including panels, inverter, mounting hardware, cables, and permits. Typical range: $600-$1,850 for 400W-800W systems.
After tax credit: Multiply by 0.70 (30% federal ITC reduces cost)
Self-Consumption (%)
Percentage of solar energy you use directly vs. exporting to grid. Higher self-consumption = better ROI.
Typical values: 60-70% (home during day), 40-50% (away during day), 80-90% (with battery)
Understanding Your Results
Annual Savings
How much money you save per year by reducing electricity bills. This is your annual return on investment.
Payback Period
Number of years until your system pays for itself. Typical range: 6-12 years for balcony systems.
25-Year Savings
Total savings over panel lifetime (typically 25 years). This shows long-term financial benefit.
Pro Tip
Try different scenarios: compare 400W vs 800W, test different orientations, or see how self-consumption affects ROI. Our free calculator updates results in real-time as you adjust parameters.