SAVE
$0+
Over 25 Years
Most homeowners need:
25-year cost comparison for a $300/month US electric bill.
Without solar
25-year utility cost
$82,100
Rates rise ~3% per year (EIA avg.)
With solar
Net system cost
$21,600
After 30% federal ITC
Your savings
Difference
+$60,600
Estimated lifetime advantage
A 2,500 square foot home in the US typically needs 26 solar panels (10.3 kW) at national average electricity rates and sun hours — $21,600 after the 30% ITC with 11.0-year payback. State-by-state, system size ranges from 7.1 kW in Arizona to 14.9 kW in Alaska, and payback spans 3.3–18.7 years.
Start here: National 2,500 sq ft guide · System size calculator · $200/month bill by state
| Metric | US average (2,500 sq ft) |
|---|---|
| Est. monthly usage | ~1,152 kWh |
| System size | 10.3 kW |
| Panels (400W) | 26 |
| Net cost after ITC | $21,600 |
| Simple payback | 11.0 years |
| 25-year savings | $60,600+ |
Formula: kW = Annual kWh ÷ (Peak sun hours × 365 × 0.82)
| Fastest payback | Slowest payback | |
|---|---|---|
| State | Hawaii | Washington |
| System | 7.7 kW · 20 panels | 11.5 kW · 29 panels |
| After ITC | $16,200 | $24,200 |
| Payback | 3.3 yrs | 18.7 yrs |
High electricity rates (e.g. Hawaii, California, Massachusetts) often beat sunny low-rate states for 2,500 sq ft payback.
| State | System | Panels | After ITC | Payback |
|---|---|---|---|---|
| Alabama | 8.7 kW | 22 | $18,300 | 11.4 yrs |
| Alaska | 14.9 kW | 38 | $31,300 | 11.1 yrs |
| Arizona | 7.1 kW | 18 | $14,900 | 9.4 yrs |
| Arkansas | 9.2 kW | 24 | $19,400 | 13.6 yrs |
| California | 8.0 kW | 20 | $16,700 | 4.7 yrs |
| Colorado | 8.4 kW | 21 | $17,600 | 10.3 yrs |
| Connecticut | 11.0 kW | 28 | $23,100 | 7.7 yrs |
| Delaware | 10.3 kW | 26 | $21,600 | 12.1 yrs |
| Florida | 8.1 kW | 21 | $17,000 | 10.5 yrs |
| Georgia | 8.9 kW | 23 | $18,700 | 11.9 yrs |
| Hawaii | 7.7 kW | 20 | $16,200 | 3.3 yrs |
| Idaho | 9.2 kW | 24 | $19,400 | 14.7 yrs |
| Illinois | 10.5 kW | 27 | $22,000 | 11.7 yrs |
| Indiana | 10.3 kW | 26 | $21,600 | 12.8 yrs |
| Iowa | 10.3 kW | 26 | $21,600 | 15.1 yrs |
| Kansas | 9.2 kW | 24 | $19,400 | 12.2 yrs |
| Kentucky | 10.0 kW | 26 | $21,100 | 15.4 yrs |
| Louisiana | 8.6 kW | 22 | $18,000 | 13.1 yrs |
| Maine | 10.7 kW | 27 | $22,600 | 8.5 yrs |
| Maryland | 10.3 kW | 26 | $21,600 | 11.8 yrs |
| Massachusetts | 11.0 kW | 28 | $23,100 | 7.8 yrs |
| Michigan | 11.3 kW | 29 | $23,700 | 11.1 yrs |
| Minnesota | 10.3 kW | 26 | $21,600 | 12.1 yrs |
| Mississippi | 8.9 kW | 23 | $18,700 | 12.7 yrs |
| Missouri | 9.6 kW | 25 | $20,200 | 13.2 yrs |
| Montana | 9.6 kW | 25 | $20,200 | 13.4 yrs |
| Nebraska | 9.6 kW | 25 | $20,200 | 14.7 yrs |
| Nevada | 7.2 kW | 19 | $15,200 | 8.8 yrs |
| New Hampshire | 11.0 kW | 28 | $23,100 | 8.8 yrs |
| New Jersey | 10.5 kW | 27 | $22,000 | 10.4 yrs |
| New Mexico | 7.4 kW | 19 | $15,600 | 9.0 yrs |
| New York | 10.7 kW | 27 | $22,600 | 8.4 yrs |
| North Carolina | 8.9 kW | 23 | $18,700 | 12.1 yrs |
| North Dakota | 10.3 kW | 26 | $21,600 | 16.4 yrs |
| Ohio | 10.7 kW | 27 | $22,600 | 12.8 yrs |
| Oklahoma | 8.7 kW | 22 | $18,300 | 13.2 yrs |
| Oregon | 10.3 kW | 26 | $21,600 | 14.2 yrs |
| Pennsylvania | 11.0 kW | 28 | $23,100 | 11.4 yrs |
| Rhode Island | 10.7 kW | 27 | $22,600 | 7.6 yrs |
| South Carolina | 8.7 kW | 22 | $18,300 | 11.3 yrs |
| South Dakota | 9.6 kW | 25 | $20,200 | 14.1 yrs |
| Tennessee | 9.2 kW | 24 | $19,400 | 13.2 yrs |
| Texas | 8.2 kW | 21 | $17,300 | 10.4 yrs |
| Utah | 8.0 kW | 20 | $16,700 | 12.4 yrs |
| Vermont | 11.3 kW | 29 | $23,700 | 9.6 yrs |
| Virginia | 9.8 kW | 25 | $20,600 | 12.3 yrs |
| Washington | 11.5 kW | 29 | $24,200 | 18.7 yrs |
| West Virginia | 11.0 kW | 28 | $23,100 | 15.5 yrs |
| Wisconsin | 10.7 kW | 27 | $22,600 | 11.0 yrs |
| Wyoming | 9.2 kW | 24 | $19,400 | 14.0 yrs |
Estimates use EIA state rates, NREL sun hours, and typical kWh/sqft intensity. National methodology.
2,500 sq ft maps to roughly $188/month in utility spend nationally — close to our $200/month bill tier.
| Sizing method | Best when you know… | National guide |
|---|---|---|
| Sq ft (this page) | Home size | 2,500 sq ft |
| Monthly bill | Utility bill amount | $200/mo |
Use both: if your actual bill differs from the sq ft estimate, trust your kWh usage from the utility statement.
Direct answers for US homeowners — sized for a 2,500 sq ft home.
System size and payback vary by electricity rate and sun hours — see your state.
Your target maps to roughly a $200/month electric bill nationally.
$200 $200/month electric bill guide