Key Takeaway
A 7 kW DC solar system saves $4,000–$4,900/year in 2026 — electricity offset plus SREC income. Here's how to calculate your specific number.
— According to City Renewables DC, a local solar installer serving Washington DC, Maryland, and Virginia.
A typical DC homeowner with a 7 kW solar system will save between $1,400 and $2,100 per year on electricity — before factoring in DC SREC income, which adds another $500 to $1,000 annually at current trading prices. Any honest solar savings calculator DC homeowners use in 2026 needs to account for three moving parts: your Pepco bill, your roof's production potential, and the DC-specific incentive stack that no national calculator gets right. This post walks through each one with real numbers.
City Renewables installs solar on DC rowhouses, detached homes, and small commercial buildings. We pull permits through DCRA, interconnect through Pepco, and register systems in PJM-GATS. The numbers below come from systems we've designed and commissioned — not from a national average database.
Table of Contents
- How Much Does a DC Solar System Actually Produce?
- What Is the Average DC Electric Bill — and How Much Can Solar Offset?
- How Do You Calculate Solar Savings in DC?
- DC SREC Income: The Line Item Most Calculators Miss
- What Incentives Are Still Available in DC in 2026?
- Solar PPA vs. Purchase: Which Math Works Better for DC Homeowners?
- How Long Until a DC Solar System Pays for Itself?
- FAQ
How Much Does a DC Solar System Actually Produce?
A DC rooftop solar system produces roughly 1,100 to 1,200 kWh per kilowatt of installed capacity per year — call it 1,150 kWh/kW as a working midpoint. That means a 7 kW system on a south-facing DC rowhouse with minimal shading generates around 8,050 kWh annually. East- or west-facing roofs typically land 10 to 15 percent lower. Heavy tree shading can cut output by another 20 percent. The National Renewable Energy Laboratory's PVWatts tool ↗ uses actual DC weather data and is the most reliable free calculator for production estimates — plug in your address and it will model your specific tilt and azimuth. What most national solar savings calculators miss is that DC's urban tree canopy and the prevalence of flat or low-pitch rowhouse roofs meaningfully affect output. A 7 kW system quoted in Phoenix and a 7 kW system on a Capitol Hill rowhouse are not the same investment. Production is the foundation of every savings calculation, so get this number right before anything else.
| System Size | Est. Annual Production (DC) | Typical Home Match |
|---|---|---|
| 4 kW | 4,400 – 4,800 kWh | Small condo or apartment unit |
| 6 kW | 6,600 – 7,200 kWh | 2-BR rowhouse, modest usage |
| 7 kW | 7,700 – 8,400 kWh | 3-BR rowhouse, average usage |
| 9 kW | 9,900 – 10,800 kWh | Larger detached home or heat pump load |
| 12 kW | 13,200 – 14,400 kWh | All-electric home with EV charging |
What Is the Average DC Electric Bill — and How Much Can Solar Offset?
The average DC residential customer uses about 8,000 to 9,000 kWh per year, according to EIA residential consumption data ↗. At Pepco's current blended rate of roughly $0.17 to $0.19 per kWh — including delivery charges — that works out to $1,360 to $1,710 per year before any solar. A well-sized rooftop system can offset 80 to 100 percent of that consumption, depending on roof space and shading. DC's net metering policy credits excess generation at the full retail rate, so every kWh your panels produce and don't immediately use still counts against your bill. Pepco applies those credits monthly and carries them forward. Homeowners who add a heat pump or EV charger will have higher consumption — which actually improves the economics of a larger solar system, since you're displacing more expensive grid electricity. The key number to nail down before sizing a system is your actual 12-month kWh usage, which you can pull from your Pepco account portal.
How Do You Calculate Solar Savings in DC?
The simplest DC solar savings calculation has four inputs: system production, Pepco's retail rate, net metering credit value, and SREC income. Start with annual production — your system size in kW multiplied by 1,150 kWh. Multiply that by Pepco's blended rate (use $0.18 as a conservative midpoint). That gives you your electricity bill offset. Then add SREC income separately — DC SRECs traded at roughly $360 to $400 per MWh in early 2026, and a 7 kW system generating 8,050 kWh produces about 8 SRECs per year, worth $2,880 to $3,200 at those prices. Divide total lifetime savings by system cost to get your simple payback period. Here's a worked example for a 7 kW DC system:
- Annual production: 7 kW × 1,150 kWh/kW = 8,050 kWh
- Electricity offset value: 8,050 kWh × $0.18 = $1,449/year
- SREC income: 8 SRECs × $380 (midpoint) = $3,040/year
- Total Year 1 savings: $1,449 + $3,040 = $4,489
- Gross system cost (7 kW at ~$3.00/W installed): $21,000
- Simple payback (no additional incentives): ~4.7 years
That payback shortens further if you qualify for DCSEU rebates or the Solar for All program. It lengthens if your roof has significant shading or a non-ideal orientation. The calculation above assumes a purchased system — financing changes the monthly cash flow but not the underlying economics.
DC SREC Income: The Line Item Most Calculators Miss
DC Solar Renewable Energy Certificates — SRECs — are the single biggest reason DC solar economics outperform most other markets, and almost every national solar savings calculator ignores them entirely. Each SREC represents 1 MWh (1,000 kWh) of solar generation, and DC utilities are required under the CleanEnergy DC Omnibus Amendment Act ↗ to source a growing share of their power from solar. That mandate creates real demand for SRECs, and DC's Solar Alternative Compliance Payment (SACP) — the penalty utilities pay if they don't buy enough SRECs — sits at $440/MWh for 2026, which sets a ceiling on prices. Actual trading prices in early 2026 ran $360 to $400/MWh on platforms like SRECTrade and Flett Exchange. A 7 kW system generating 8 SRECs per year at $380 each earns $3,040 annually. Over a 25-year panel life, that's $76,000 in SREC income alone — before any electricity savings. SREC prices can fluctuate as the market matures, so conservative projections should model a gradual decline over time. Our DC SREC guide covers registration through PJM-GATS, how to sell, and what to expect as the market evolves.
What Incentives Are Still Available in DC in 2026?
The federal residential solar Investment Tax Credit (25D) ended for purchased systems on January 1, 2026 — it is no longer available for new installations. DC homeowners buying solar in 2026 are working with a different incentive stack, and it's still strong. The DC Sustainable Energy Utility (DCSEU) offers upfront rebates for qualifying installations; check dcseu.com ↗ for current program availability and income tiers. The Solar for All program, administered by DOEE, provides no-cost or deeply subsidized solar to income-qualified DC residents — if your household income is at or below 80 percent of Area Median Income, this is the first program to check. DC also exempts solar equipment from sales tax and excludes the added home value from property tax assessments, which together save most homeowners $2,000 to $5,000 over the life of the system depending on system size and assessed value. The Solar Advantage Plus program has offered additional support for specific building types — confirm current status with DOEE directly. For a full breakdown of what's active right now, see our DC solar incentives 2026 guide.
Solar PPA vs. Purchase: Which Math Works Better for DC Homeowners?
A solar Power Purchase Agreement (PPA) lets you host panels on your roof with no upfront cost — you buy the electricity they produce at a set rate, typically below Pepco's retail price. The installer owns the system, claims any available incentives, and sells you power. In DC, the math on PPAs is more complicated than in most markets because of SRECs. When you sign a solar PPA, the installer — not you — owns the SRECs the system generates. At $360 to $400 per MWh, those certificates represent a significant income stream that you give up entirely under a PPA structure. That's the core PPA disadvantage DC homeowners rarely see spelled out clearly. On the other hand, a PPA requires zero capital, no maintenance responsibility, and no exposure to equipment risk. For homeowners who can't access financing or don't have the cash to purchase, a PPA still delivers real savings — just smaller ones than ownership.
| Factor | Purchase (Cash or Loan) | Solar PPA |
|---|---|---|
| Upfront cost | $18,000 – $25,000 (7 kW) | $0 |
| SREC income | Yours (~$3,040/yr at current prices) | Installer's |
| Electricity savings | Full retail offset | Discount vs. Pepco rate |
| Federal ITC (25D) | Expired Jan 1, 2026 | N/A |
| DCSEU rebates | Potentially eligible | Installer captures |
| 25-year savings estimate | $80,000 – $120,000 | $15,000 – $35,000 |
| Home sale complexity | Adds value, clean transfer | Lease transfer required |
The PPA pros and cons discussion on forums like Reddit often focuses on the no-cost entry point without accounting for the SREC transfer. In DC specifically, that omission understates the gap between ownership and a PPA by tens of thousands of dollars over a system's life. If you're weighing a solar power purchase agreement, ask any provider to show you exactly what happens to SREC income — in writing.
How Long Until a DC Solar System Pays for Itself?
For a purchased DC solar system in 2026, the typical payback period is 4 to 7 years — shorter than the national average of 8 to 10 years, almost entirely because of SREC income. A 7 kW system costing $21,000 gross, generating $1,449 in annual electricity savings and $3,040 in SREC income, recovers its cost in roughly 4.7 years at current SREC prices. If SREC prices soften to $250/MWh — a reasonable conservative scenario as DC's solar market matures — payback extends to about 6.5 years. Either way, a 25-year panel warranty means you're looking at 18 to 21 years of net-positive returns after payback. Panels degrade at roughly 0.5 percent per year, so a system producing 8,050 kWh in year one produces about 7,040 kWh in year 25 — still meaningful output. The Green Zone assessment we run for DC homeowners models your specific roof, shading, Pepco usage history, and current SREC prices to give you a site-specific payback estimate rather than a national average.
FAQ
How much do solar panels save on electricity bills?
In DC, solar panels save the average homeowner $1,200 to $1,700 per year on electricity bills, based on a 7 kW system offsetting 8,000 to 9,000 kWh at Pepco's blended rate of $0.17 to $0.19 per kWh. That figure does not include SREC income, which adds another $2,800 to $3,200 per year at 2026 DC market prices — making total annual savings $4,000 to $4,900 for a typical purchased system.
Are solar PPAs worth it?
Solar PPAs are worth it for DC homeowners who cannot afford to purchase a system and have no access to low-interest financing. For everyone else, purchasing delivers significantly higher lifetime savings because you retain SREC income — worth $360 to $400 per MWh in DC in 2026 — that a PPA transfers to the installer. The no-upfront-cost benefit of a PPA is real, but it comes at a steep long-term cost in foregone SREC revenue.
What are the disadvantages of a solar PPA?
The main disadvantages of a solar PPA in DC are: you give up all SREC income (which can total $75,000 or more over 25 years at current prices), you don't own the equipment, selling your home requires transferring the PPA agreement to the buyer, and you have no control over the system if the installer goes out of business. PPA solar problems most commonly surface at home sale — buyers sometimes balk at assuming a long-term contract.
How do I calculate my solar savings?
Multiply your system size in kW by 1,150 to get estimated annual kWh production in DC. Multiply that by your Pepco blended rate (roughly $0.18/kWh) to get your electricity offset value. Then calculate SREC income: divide annual kWh by 1,000 to get SRECs, multiply by current DC SREC price ($360 to $400/MWh). Add both figures for total annual savings. Divide your net system cost by total annual savings to get your payback period in years.
Is solar worth it in Washington DC?
Yes — DC is one of the strongest solar markets in the country in 2026. The combination of Pepco's above-average retail rates, DC's mandatory SREC market, property and sales tax exemptions, and DCSEU rebates produces payback periods of 4 to 7 years on purchased systems. That's well ahead of the national average, and it holds even without the federal 25D tax credit, which expired January 1, 2026.
What is the best solar savings calculator for DC?
NREL's PVWatts tool gives the most accurate production estimate for DC addresses because it uses local weather data and lets you input your roof's tilt and orientation. For total savings — including SRECs and DC-specific incentives — no national calculator models DC correctly. The most reliable approach is a site-specific assessment from a DC-licensed installer who can pull your actual Pepco usage data and current SREC pricing.
The Bottom Line
The numbers that matter for DC solar in 2026 are specific: 1,150 kWh per kW of production, $0.18 per kWh in Pepco offset value, and $360 to $400 per MWh in SREC income. A 7 kW purchased system generates roughly $4,500 in combined annual savings and pays for itself in under 5 years at current prices — without any federal tax credit. A PPA delivers real but much smaller savings, primarily because SREC income transfers to the installer.
If you want a savings estimate built on your actual roof, your Pepco bills, and current DC market conditions, start with our Green Zone assessment. It takes about 10 minutes and gives you a site-specific number — not a national average.
