US Solar Production by System Size: Physics-Based Benchmarks
Last updated: 2026-04-06 · Solar Benchmark
US Solar Production by System Size: Physics-Based Benchmarks
A 6kW solar system in the continental US produces about 8,100 kWh per year on average. A 10kW system produces about 13,500 kWh. Every kilowatt of installed capacity adds roughly 1,340 kWh/year at the national average, but that multiplier shifts from 1,050 kWh/kW in the Pacific Northwest to 1,825 kWh/kW in Arizona.
Annual Production Benchmarks by System Size
Expected annual production for a south-facing system at 30-degree tilt. National average uses pvlib simulation on Open-Meteo ERA5 weather data, averaged across US continental locations 2015–2024.
| System Size | US Avg Annual (kWh) | Monthly Average | Typical Home Match |
|---|---|---|---|
| 4 kW | 5,360 | 447 | Small home, 400–600 sq ft |
| 5 kW | 6,700 | 558 | Smaller home, low usage |
| 6 kW | 8,040 | 670 | Typical 1,500–2,000 sq ft home |
| 7 kW | 9,380 | 782 | Larger typical home |
| 8 kW | 10,720 | 893 | High-usage home or EV charging |
| 10 kW | 13,400 | 1,117 | Large home or high consumption |
| 12 kW | 16,080 | 1,340 | Maximum typical residential |
(Source: pvlib physics modeling, Open-Meteo ERA5 weather data)
Regional Production by System Size
Production varies significantly by location. The table below shows annual kWh for each system size across the main US solar regions.
| System Size | Southwest Desert | California Coast | Southeast | Mid-Atlantic | Midwest | New England | Pacific NW |
|---|---|---|---|---|---|---|---|
| 4 kW | 7,300 | 6,280 | 6,240 | 5,280 | 4,960 | 4,640 | 4,200 |
| 6 kW | 10,950 | 9,420 | 9,360 | 7,920 | 7,440 | 6,960 | 6,300 |
| 8 kW | 14,600 | 12,560 | 12,480 | 10,560 | 9,920 | 9,280 | 8,400 |
| 10 kW | 18,250 | 15,700 | 15,600 | 13,200 | 12,400 | 11,600 | 10,500 |
| 12 kW | 21,900 | 18,840 | 18,720 | 15,840 | 14,880 | 13,920 | 12,600 |
States by region: Southwest Desert (AZ, NV, inland CA), California Coast (coastal CA), Southeast (FL, TX, GA, SC), Mid-Atlantic (NJ, MD, VA, NC), Midwest (OH, IL, IN, MO), New England (MA, NY, CT, RI), Pacific Northwest (WA, OR).
(Source: pvlib physics modeling, Open-Meteo ERA5 weather data, 2015–2024 averages)
What the Specific Yield Number Tells You
Specific yield measures annual production per installed kilowatt: kWh/kWp/year. It lets you compare systems of different sizes on equal footing.
| Region | Specific Yield (kWh/kWp/year) |
|---|---|
| Southwest Desert | ~1,820 |
| California Coast | ~1,570 |
| Southeast | ~1,560 |
| Mid-Atlantic | ~1,320 |
| Midwest | ~1,240 |
| New England | ~1,160 |
| Pacific Northwest | ~1,050 |
A system producing below 1,000 kWh/kWp/year anywhere in the continental US is underperforming. Below 900 kWh/kWp/year is a red flag. Learn more about how these benchmarks are calculated at /resources/methodology.
What Affects Actual Production
- Location: The single largest variable. A 6kW system in Phoenix produces 39% more annually than the same system in Seattle.
- Roof orientation: South-facing at 30 degrees is the reference. West-facing costs about 13% annually. East-facing costs about 15%. North-facing in the northern US cuts output by 20–25%.
- System age and degradation: PERC panels lose about 0.5%/year. A 6kW system producing 8,040 kWh in year one produces roughly 7,640 kWh in year 10.
- Shading: Even partial shading on a string-wired system can reduce output by 10–25% depending on shade patterns and inverter type.
- Soiling: In dry western climates without regular rainfall, dust and debris on panels cost 3–7% annually.
- Inverter efficiency: Microinverter and DC optimizer systems typically outperform string inverters by 5–15% when shading or roof complexity is involved.
Frequently Asked Questions
Q: How do I know if my system is producing what it should for its size?
A: Calculate your specific yield: divide annual kWh by system size in kW. A 6kW system producing 7,200 kWh/year has a specific yield of 1,200 kWh/kWp. Compare that to the regional benchmark in the table above. If you're 15%+ below the regional number with no obvious shading or soiling, it's worth investigating.
Q: Why does my monitoring app show different numbers than these benchmarks?
A: These benchmarks reflect expected production given actual historical weather conditions. Your monitoring app shows what your system actually produced. The gap between expected and actual is the key diagnostic signal. A system producing 20% below its physics-based benchmark for its size and location may have a hardware or configuration issue.
Q: What system size does a typical US home need?
A: Most US homes use 10,500–11,500 kWh/year. A 6kW system covers that in the Southeast (produces ~9,360 kWh) but falls short in the Midwest (produces ~7,440 kWh). A 8kW system covers average usage across most of the continental US. Homes with EVs or electric heat typically need 10kW or more.
Q: Do larger systems always have higher specific yield than smaller ones?
A: No. Specific yield stays roughly constant across system sizes when conditions are the same. A 12kW system in the same location with the same orientation and tilt produces twice the kWh of a 6kW system, but the yield per kilowatt is nearly identical. The exception is inverter clipping: larger DC arrays paired with undersized AC inverters lose proportionally more to clipping at peak summer output.
Data: pvlib physics modeling + Open-Meteo ERA5 weather data | Last updated: 2026-04-06 | Solar Benchmark