Est. net savings
$7,200
Over 25 Years · 2.5 kW example · flat rates · no federal credit
Typical result:
Assumes 3%/yr rate increases, 0.5%/yr panel degradation and no federal tax credit (the 30% §25D credit ended for systems installed after Dec 31, 2025). How we calculate
Without solar
25-year utility bills
$14,100
Rates rise ~3% per year
With solar
System cost + remaining bills
$6,900
Installed cost, no federal credit
Difference
Estimated 25-year net
+$7,200
Before any state or utility incentives
Short answer: A $50 monthly electric bill needs about 3 to 7 solar panels (400W each), or roughly 1 to 2.6 kW of solar, in the sample cities below. The exact number depends on three things: your electricity rate, your local peak sun hours, and your panel wattage. In 2026, homeowners who buy a system also no longer get the 30% federal tax credit, which changes the cost and payback math.
Last updated: October 3, 2026. All figures are estimates for planning, not installer quotes.
Your bill is a dollar figure, not a usage figure, so the first step is converting dollars to kilowatt-hours (kWh). Divide $50 by your rate per kWh. According to EIA’s Electric Power Monthly (Table 5.6.A), the US average residential price was about 18.3¢/kWh in mid-2026, with state averages ranging from roughly 13¢ in Louisiana to over 40¢ in Hawaii.
At 18.3¢/kWh, a $50 bill equals about 273 kWh per month, or 9 kWh per day. The same $50 buys far fewer kWh in a high-rate state, which is why neighbors in different states need very different system sizes.
Monthly kWh a $50 bill buys at different residential rates (EIA, mid-2026):
| Residential Rate | Example | Monthly kWh at $50 | Daily kWh |
|---|---|---|---|
| 12.7¢ | Louisiana (lowest state, July 2026) | 394 kWh | 13.0 kWh |
| 15.1¢ | Florida | 331 kWh | 10.9 kWh |
| 15.9¢ | Texas | 314 kWh | 10.3 kWh |
| 18.3¢ | US average | 273 kWh | 9.0 kWh |
| 29.9¢ | New York | 167 kWh | 5.5 kWh |
| 34.7¢ | California | 144 kWh | 4.7 kWh |
Daily kWh = monthly kWh ÷ 30.4.
One caution: many utility bills include fixed monthly charges that solar cannot offset. If $8 of your $50 is a customer charge, you actually use fewer kWh than the table shows, and you need fewer panels. Look at the “kWh used” line on your bill for the most accurate starting point. Use our solar system size calculator to run your own rate and location.
The savings calculator loads your state's average electricity rate, sun hours and net-metering rule. Then enter your own bill and installer quote.
Free · No signup · Runs in your browser
Once you know your daily kWh, panel count follows from your location’s peak sun hours (the daily equivalent of full-strength sunlight). NREL’s PVWatts calculator gives address-level figures.
The sizing formula: System size (kW) = daily kWh ÷ peak sun hours ÷ 0.80
The 0.80 factor is a conservative allowance for inverter, wiring, temperature, and soiling losses. PVWatts’ default loss assumption is somewhat lower, so real systems can come in slightly smaller than this formula suggests.
National example: 9.0 kWh ÷ 4.5 peak sun hours ÷ 0.80 = 2.5 kW, which is 6–7 panels at 400W.
System size and panel count for a $50 bill in six sample cities:
| City | Rate Used | Peak Sun Hours (approx.) | System Size | Panels (400W) |
|---|---|---|---|---|
| Los Angeles, CA | 34.7¢ (CA) | 5.6 | 1.06 kW | 3 |
| New York, NY | 29.9¢ (NY) | 4.1 | 1.68 kW | 5 |
| Phoenix, AZ | 15.2¢ (AZ) | 6.5 | 2.08 kW | 6 |
| Denver, CO | 17.1¢ (CO) | 5.3 | 2.27 kW | 6 |
| Dallas, TX | 15.9¢ (TX) | 5.45 | 2.37 kW | 6 |
| Atlanta, GA | 16.4¢ (GA) | 4.8 | 2.61 kW | 7 |
Rates: EIA Electric Power Monthly, mid-2026 (state residential averages; utility rates vary). Peak sun hours: rounded annual averages from NREL-derived datasets, which differ slightly by source; confirm yours in PVWatts. Panel counts are rounded up.
Chart summary: System size depends more on your electricity rate than on sunshine. Los Angeles and New York need the smallest systems because their high rates mean $50 buys little electricity. Atlanta needs the largest of the six because it pairs a moderate rate with only moderate sun.
Two practical notes. First, east- or west-facing and partly shaded roofs produce less than an unshaded south-facing roof, so you may need an extra panel or two. Ask installers to model your roof with satellite or shade data. Second, panels lose a small amount of output each year (NREL’s review of field data found a median of about 0.5% per year), so a system sized exactly to today’s bill will cover slightly less of it in year 25. For wider price context, see our guide to how much solar panels cost in 2026.
Installed residential solar prices in 2026 generally run $2.50 to $3.50 per watt, with an average around $2.75 per watt, according to 2026 pricing guides built on EnergySage marketplace data and NREL and LBNL benchmarks. Small systems often land at the higher end because fixed costs (permits, inspection, design, sales) are spread over fewer watts, and some installers set minimum system sizes.
Important 2026 change: The 30% federal Residential Clean Energy Credit (Section 25D) ended for expenditures made after December 31, 2025, under the One Big Beautiful Bill Act. The IRS treats an expenditure as made when installation is completed, so a homeowner-owned system finished in 2026 does not qualify, even if you signed or paid in 2025. Systems completed by the end of 2025 can still claim the credit on a 2025 return (Form 5695), and unused credit can carry forward. Any quote still advertising “30% off with the federal tax credit” for a 2026 purchase deserves scrutiny.
Estimated installed cost by system size (before state, local, or utility incentives):
| System Size | Panels (400W) | At $2.50/W | At $2.75/W | At $3.50/W |
|---|---|---|---|---|
| 1.0 kW | 3 | $2,500 | $2,750 | $3,500 |
| 1.5 kW | 4 | $3,750 | $4,125 | $5,250 |
| 2.0 kW | 5 | $5,000 | $5,500 | $7,000 |
| 2.5 kW | 7 | $6,250 | $6,875 | $8,750 |
| 3.0 kW | 8 | $7,500 | $8,250 | $10,500 |
Many states, utilities, and local governments run their own rebates, tax credits, or property-tax exemptions. Search DSIRE, the database of state incentives for renewables and efficiency, for what applies at your address. Net metering rules matter too: if your utility credits excess solar at less than the retail rate (as in California’s net billing program for new customers since 2023), your savings and payback will be worse than the simple estimates below. Use our solar net metering calculator to check.
The honest answer: it depends on your rate, your roof, and how long you will stay. A key point many guides miss is that a system sized to eliminate a $50 bill saves at most about $600 a year (12 × $50), no matter which state you live in. What changes by state is how big, and therefore how expensive, the system must be. High-rate states need a smaller system for the same $50 bill, so they pay back faster.
Estimated simple payback for a $50 bill (system priced at $2.75/W, no federal credit):
| City | System Size | Est. Cost | Annual Savings (max) | Simple Payback |
|---|---|---|---|---|
| Los Angeles, CA | 1.06 kW | ~$2,900 | ~$600 | 4.9 yrs |
| New York, NY | 1.68 kW | ~$4,600 | ~$600 | 7.7 yrs |
| Phoenix, AZ | 2.08 kW | ~$5,700 | ~$600 | 9.5 yrs |
| Denver, CO | 2.27 kW | ~$6,200 | ~$600 | 10.4 yrs |
| Dallas, TX | 2.37 kW | ~$6,500 | ~$600 | 10.9 yrs |
| Atlanta, GA | 2.61 kW | ~$7,200 | ~$600 | 12.0 yrs |
Simple payback = cost ÷ annual savings. Assumes the system offsets the full $50 bill with no fixed charges, retail-rate net metering, flat rates, and no incentives. Very small systems (under about 2 kW) usually cost more per watt than $2.75, so treat Los Angeles and New York as best-case figures. California’s net billing rules would also lengthen the Los Angeles payback.
Chart summary: Bar color runs from green (fastest payback) to red (slowest). Payback tracks system size almost one-for-one, so the smaller system a $50 bill requires, the sooner it pays for itself. Los Angeles and New York are best-case figures, since very small systems usually cost more per watt than $2.75.
Solar tends to be a good fit if you own your roof, plan to stay at least 12 years, live in a high-rate area, and expect to use more electricity later (an EV or heat pump would raise your bill and make a slightly larger system worthwhile). It is a weaker fit if your roof is shaded or old, your rates are low, or you may move soon. Model your own numbers with our solar savings calculator.
Take the national example: a 2.5 kW system at about $6,875 that offsets a $50 monthly bill ($600 in year one). Assuming the bill stays flat and panels lose 0.5% of output each year, cumulative savings reach about $14,100 over 25 years, a net gain of roughly $7,300 after the system cost.
Chart summary: Both lines start below zero at the upfront cost and cross zero when the system has paid for itself: about year 12 in the base case and about year 16 in the high-cost case. By year 25 the base case is ahead by about $7,300 and the high-cost case by about $5,400. Rates are held flat here, so any utility price increase would lift both lines.
At the low end of the cost range ($2.50/W, about $6,250) the 25-year net gain is roughly $7,900; at the high end ($3.50/W, about $8,750) it falls to roughly $5,400. These figures leave out inverter replacement (string inverters often need replacing once in a system’s life) and financing costs, both of which would reduce the gain; EIA data showing US residential prices about 5% above a year earlier in June 2026 point the other way. Because the numbers depend heavily on your installer quote, compare at least three, and use our solar payback calculator with your actual price and rate.
Direct answers for US homeowners — sized for a $50/month electric bill.
Electricity rates and incentives vary — see data for your state.
Estimates only — not tax, legal or financial advice. Get at least three installer quotes and confirm incentives with your utility and a tax professional.