Are Solar Panels Worth It in Washington DC?
In Washington DC, 5 kW of panels costs about $16,000 and pays for itself in 8 years and 8 months, saving roughly $46,651 over 25 years.
The average Washington DC home uses 639 kWh of electricity a month and pays $162 for it. Covering 90% of that takes roughly 5 kW of panels, which at the Washington DC average of $3.20 per watt is about $16,000 installed. Against a bill that drops to around $28 a month, the system breaks even in 8 years and 8 months and leaves about $46,651 in your pocket over a 25-year life.
Two things drive that number more than the panels themselves. Washington DC power costs 25.40¢ per kWh, so every kilowatt-hour you generate is worth exactly that much and rises with the utility every year — the model assumes 4% a year. And since the 2026 tax year there is no federal residential tax credit: the 30% credit under Section 25D ended on 31 December 2025, so a cash or loan purchase now carries the full price. The calculator below opens on the Washington DC numbers; replace them with your own quote, your own bill, and any rebate your utility still offers.
Solar Panel Payback & ROI Calculator
Estimate upfront costs, monthly utility savings, and the break-even payback period of your solar panel system
Results
Payback Period
— Years
25-Year Utility Savings: $79,247 · Net Upfront Cost: $24,000
Net Lifetime Savings
$55,247
Return on Investment (ROI): 230.2%
Internal Rate of Return (IRR)
10.23%
Annual Savings: $2,040
Monthly Bill Savings
$170
Net Upfront Cost: $24,000
Cumulative Savings vs. Net Upfront Cost
25-Year Amortization Schedule
| Year | Panel Output | Annual Savings | Net Cash Flow |
|---|---|---|---|
| 1 | 100.0% | $2,040 | -$21,960 |
| 2 | 99.5% | $2,111 | -$19,849 |
| 3 | 99.0% | $2,184 | -$17,665 |
| 4 | 98.5% | $2,260 | -$15,404 |
| 5 | 98.0% | $2,339 | -$13,065 |
| 6 | 97.5% | $2,421 | -$10,644 |
| 7 | 97.0% | $2,505 | -$8,140 |
| 8 | 96.6% | $2,592 | -$5,548 |
| 9 | 96.1% | $2,682 | -$2,866 |
| 10 | 95.6% | $2,775 | -$90 |
| 11 | 95.1% | $2,872 | +$2,782 |
| 12 | 94.6% | $2,972 | +$5,754 |
| 13 | 94.2% | $3,075 | +$8,829 |
| 14 | 93.7% | $3,182 | +$12,012 |
| 15 | 93.2% | $3,293 | +$15,305 |
| 16 | 92.8% | $3,408 | +$18,713 |
| 17 | 92.3% | $3,526 | +$22,239 |
| 18 | 91.8% | $3,649 | +$25,888 |
| 19 | 91.4% | $3,776 | +$29,665 |
| 20 | 90.9% | $3,908 | +$33,572 |
| 21 | 90.5% | $4,044 | +$37,616 |
| 22 | 90.0% | $4,184 | +$41,800 |
| 23 | 89.6% | $4,330 | +$46,130 |
| 24 | 89.1% | $4,481 | +$50,610 |
| 25 | 88.7% | $4,636 | +$55,247 |
Beyond this calculator
Upload instead of typing
Drop in a paystub, bank statement or screenshot — the AI reads it and fills these fields for you.
Keep the result
Keep these numbers in Budget Tracker — a one-off calculation becomes something that updates itself.
Documents in one sentence
Describe an invoice and the AI writes it. PDF without watermarks, free.
Payback in Washington DC by what you pay per watt
Same 5 kW system and the same $162 bill — only the installer quote changes. No federal credit, no state rebate, 4% annual utility inflation.
| Quoted price per watt | System cost | Payback | Net 25-year saving |
|---|---|---|---|
| $2.80 | $14,000 | 7 years and 9 months | $48,651 |
| $3.00 | $15,000 | 8 years and 2 months | $47,651 |
| $3.20 | $16,000 | 8 years and 8 months | $46,651 |
| $3.40 | $17,000 | 9 years and 2 months | $45,651 |
| $3.60 | $18,000 | 9 years and 7 months | $44,651 |
Frequently Asked Questions
- About 8 years and 8 months for a typical 5 kW system bought at the Washington DC average of $3.20 per watt. That assumes the system covers 90% of a $162 monthly bill and that power prices keep rising around 4% a year. A cheaper quote or a higher bill shortens it; a shaded roof or a cash-out at a low utility rate lengthens it.
- Around $3.20 per watt installed, so roughly $16,000 for the 5 kW system an average Washington DC home needs. Price per watt falls as the system grows — the fixed costs of permits, inverter and labour spread over more panels — which is why small systems rarely quote at the state average.
- Not for a system you buy. The residential clean energy credit (Section 25D) was ended by the One Big Beautiful Bill Act for anything installed after 31 December 2025, so a 2026 cash or loan purchase receives nothing federal. Leases and power purchase agreements are different: the company that owns the panels claims the business credit and may price some of it into your rate. State and utility programmes are unaffected — check yours and enter it as a rebate in the calculator.
- On these assumptions, yes — about $46,651 net over 25 years, on top of returning the $16,000 you spent. The reason is the 25.40¢ per kWh Washington DC charges: solar is worth whatever the power it replaces would have cost, so the same panels are a far better deal in an expensive state than a cheap one. Selling the house before the break-even point is the main way this goes wrong, though a paid-off system usually lifts the sale price.
- Roof repairs done before installation, an inverter replacement somewhere around year 12–15, and any battery. On the other side it also leaves out state and utility rebates, net-metering credits for power you export, and the property-tax exemption many states give solar equipment. Enter the ones that apply to you — the rebate field takes them directly.
Solar payback by state
US states