Delaware solar calculator
Size a Delaware home solar system from your electric bill — kW, panel count, roof area, true cost with no federal credit for 2026 installs, and payback.
Quick answer: At $0.194/kWh and 4.4 peak sun hours, a $200/month bill needs about 10.25 kW — 25 × 410 W panels covering ~50 m². Gross cost is ~$27,009 with no federal credit for systems installed after 2025, offsetting $2,400 a year for a ~11.3 year payback.
Your details
Ballpark, not gospel. Sized at 78% real-world output with the Delaware sun-hour average — confirm shading, roof angle, your utility's net-metering terms, and DNREC grant pre-approval timing with a local installer before buying. With 1:1 net metering and surplus credits carrying year to year, the calculator's retail-rate savings math is a fair approximation.
The 30% credit ended — what changed
The residential clean energy credit (26 U.S.C. § 25D) gave homeowners a 30% credit on solar installed from 2022 through 2025. The July 2025 tax law ended it: no credit is available for property placed in service after December 31, 2025. That is why every figure on this page is ~30% higher than pre-2026 guides show. If your system went live by the end of 2025, tick the box above to see the credit applied; leased systems may still benefit because the leasing company claims the commercial credit. Source: IRS — Residential Clean Energy Credit.
Typical Delaware system sizes by monthly bill
| Monthly bill | System size | Panels (410 W) | Net cost (no 2026 federal credit) | Payback |
|---|---|---|---|---|
| $100 | 5.33 kW | 13 | $14,045 | 11.7 years |
| $200 | 10.25 kW | 25 | $27,009 | 11.3 years |
| $300 | 15.17 kW | 37 | $39,973 | 11.1 years |
Computed at $0.194/kWh, 4.4 peak sun hours and $2.63/W installed, with no federal credit for 2026 installs. Run your exact bill above.
Solar in Delaware: the details
Solar cost in Delaware
Solar costs are middle-of-the-road in Delaware. The EnergySage marketplace averaged about $2.63 per watt installed in 2026, with market quotes typically landing $2.24–$3.03/W — inside the $2.50–$3.50/W national band. A typical ~10 kW system grosses around $26,400 before grants, with no federal credit for 2026 homeowner installs.
What moves the number: roof complexity and panel tier. Then subtract the DNREC grant below — it's the rare incentive that cuts the sticker price directly.
Export rules: getting paid for surplus power
Delaware law (26 Del. C. § 1014) requires every utility to offer net metering for home systems up to 25 kW — no carve-outs, no pilot caps.
Surplus kWh are credited against future bills, and unused credits carry into the next year rather than expiring. That year-to-year banking is a real advantage over states with monthly true-ups.
Practical takeaway: Delaware's net metering is as simple as it gets — full retail credits that survive the winter. Size for the year.
Delaware solar incentives
Delaware's headline incentive is the DNREC Green Energy Program grant: $0.80 per watt (up to $10,000) for Delmarva Power customers and $0.70/W (up to $5,000) for Delaware Electric Co-op members — up to half the project cost. Two conditions: you must be pre-approved before install, and you sign over your SRECs. A 10 kW Delmarva system gets up to $8,000 back.
Is solar worth it in Delaware?
Verdict: yes, especially with the grant. An ~11.3-year payback at retail-rate net metering is solid — and the DNREC Green Energy grant ($0.80/W up to $10,000 for Delmarva Power customers) can cut a 10 kW system by up to $8,000, bringing payback well under a decade. Pre-approval before install is mandatory.
Questions people actually ask
Straight answers, no fluff. Then run your own numbers above.
How many solar panels do I need in Delaware?
It follows your bill. At the Delaware average of $0.194/kWh and 4.4 peak sun hours, a $200/month bill needs about a 10.25 kW system — roughly 25 × 410 W panels covering ~50 m² of roof.
What is the average cost of solar panels in Delaware in 2026?
The EnergySage marketplace averaged about $2.63 per watt installed in 2026, with market quotes typically $2.24–$3.03/W — inside the national $2.50–$3.50/W band. A typical ~10 kW system grosses around $26,400, with no federal credit for 2026 homeowner installs — before the DNREC grant.
Does Delaware have net metering?
Yes. Delaware law (26 Del. C. § 1014) requires every utility to offer net metering for home systems up to 25 kW. Surplus kWh are credited against future bills, and unused credits carry into the next year.
Does Delaware offer any solar tax credit or rebate?
Delaware's DNREC Green Energy Program pays direct grants: $0.80 per watt (up to $10,000) for Delmarva Power customers and $0.70/W (up to $5,000) for Delaware Electric Co-op members. Pre-approval before install is required, and you must sign over your SRECs.
Is the 30% federal solar tax credit still available?
Not for homeowner purchases anymore. The residential clean energy credit (26 U.S.C. § 25D) is not available for property placed in service after December 31, 2025, under the July 2025 tax law (Public Law 119-21). Systems installed by the end of 2025 can still claim 30%, and leased systems may still benefit because the leasing company claims the commercial credit instead. (Source: IRS — Residential Clean Energy Credit.)
Is solar worth it in Delaware?
Verdict: yes, especially with the grant. An ~11.3-year payback at retail-rate net metering is solid — and the DNREC Green Energy grant ($0.80/W up to $10,000 for Delmarva Power customers) can cut a 10 kW system by up to $8,000, bringing payback well under a decade. Pre-approval before install is mandatory.
Figures last checked October 2026. Sources: residential rate and sun-hour averages via kilowattkit.com and unboundsolar.com's US sun-hours map, EIA Electric Power Monthly, NREL PVWatts/NSRDB, DSIRE, Delaware Public Service Commission; IRS — Residential Clean Energy Credit.
More US solar calculators
Compare other states: Texas, Florida, California, Arizona, North Carolina, Alabama, Alaska, Arkansas, Colorado, Connecticut, Delaware, Georgia, Hawaii, Idaho. And the national US solar calculator for country averages.
Comparing quotes? The solar cost calculator breaks down cost per watt and the solar ROI calculator maps your payback year by year. Going deeper: installation cost guide, how net metering works, how much you can save with solar and the solar batteries guide.