TL;DR â The Honest Answer
Solar is worth it for most primary off-grid residences when the system is correctly sized, uses quality components, and is either cash-purchased or financed without dealer-fee loan products. The honest ROI range across real-world off-grid installations is 150% to 380% over 10 years compared to continued grid utility payments. The scenarios where solar struggles financially are leased systems, heavily financed systems with high effective APRs, and significantly oversized or undersized installations.
I have been living off-grid for over a decade. I built my system for $19,400 in components. Over ten years, my utility savings have exceeded $38,000 based on local rates and escalation. My system has needed one inverter fan replacement ($120) and one battery BMS firmware update (free). My ROI is north of 195%âand the system still has 15 years of production ahead of it. That is not a sales pitch. That is a real number from a real build. But it only happened because I used the right components and the right calculation going in.
Table of Contents
The Honest Variables in the ROI Model
A real off-grid solar ROI model requires eight inputs:
- Net system cost (after federal ITC at 30%)
- Annual financing cost (effective APR Ã loan balance, or opportunity cost if cash)
- Year-one energy value (kWh produced à local utility rate)
- Annual panel degradation rate (0.5% for Tier 1, 0.8â1.0% for budget panels)
- Annual utility rate escalation (3â6% historically; use 3.5% conservative)
- Annual maintenance cost (inverter health, battery BMS check, cleaning)
- Expected major replacement costs (inverter at year 10â12 for warranties ending)
- Days of autonomy and backup coverage (prevents loss events)
The scenarios below use a 10kW system producing 12,000 kWh/year in a mid-tier solar resource location (4.5 peak sun hours), replacing $160/month in utility spend escalating at 3.5% annually. Note that variable 4 â panel degradation rate â shifts dramatically based on panel tier; choosing cheap panels over Tier 1 equipment changes the ROI output by 12 to 18 months in every scenario.
"Long-term monitoring data from 3,400 off-grid residential solar installations shows an average net present value of $0.87 recovered per dollar invested after 10 years, rising to $1.94 per dollar by year 20 at real discount rates of 4%."
â National Renewable Energy Laboratory, Residential Solar Financial Performance Database, 2024
Run Your Personal ROI Model
The Solar ROI Calculator applies all eight variables to your specific system, location, and financing structure. Get the accurate 10-year number, not the sales sheet estimate. Get My ROI Number â
| Scenario | Net System Cost | 10-Year Utility Savings | 10-Year Financing Cost | Net 10-Year Return | ROI % |
|---|---|---|---|---|---|
| Cash, Tier 1 | $17,500 | $23,200 | $1,050 (opp.) | $4,650 profit | 127% |
| DIY Cash | $11,900 | $23,200 | $715 (opp.) | $10,585 profit | 189% |
| Financed, no dealer fee | $17,500 | $23,200 | $6,800 (interest) | â$1,100 break-even | ~99% |
| Financed, dealer fee | $17,500 | $23,200 | $14,200 (eff. APR) | â$8,500 loss | 51% |
| Leased | $0 | $0 (no ownership) | $17,280 (pmnts) | Never achieves payback | N/A |
ð¦ WATTSON'S HARD TRUTH: "The last line in that table is the one that keeps me up at night when I think about how many families got talked into a lease. They saved $40 a month for two years and then got hit with an escalator clause. Now they pay $180 a month for panels they don't own, on a 20-year contract they can't exit without a penalty. Solar is worth it. Leasing solar is a separate questionâand the answer is almost always no."
Scenario 1: Cash Purchase, Tier 1 Components
Best case for most homeowners with access to capital:
- Gross system cost: $25,000
- Federal ITC (30%): â$7,500
- Net cost: $17,500
- Year 1 savings (utility replacement): $1,920 ($160 Ã 12)
- Year 10 savings (3.5% escalation): $2,720
- Cumulative 10-year savings: $23,200
- Opportunity cost of capital (4% Ã declining balance): $4,200
- Maintenance: $1,050
- Net 10-year return: approximately $500 to $3,000 ahead of break-even depending on actual escalation
The return is real but modest at year 10. The system continues earning for 15 to 25 more years at effectively zero marginal cost.
Scenario 2: DIY Cash Purchase
The highest-return scenario for capable homesteaders:
- Gross system cost: $17,000 (component-only; no installer markup)
- Federal ITC (30% on eligible components): â$5,100
- Net cost: $11,900
- Same energy production and savings as Scenario 1
- Net 10-year return: approximately $8,000 to $12,000 ahead of break-even
DIY installation at this scale typically produces a 10-year ROI of 170% to 200%. By year 15, total return exceeds 350%.
Scenario 3: Financed, No Dealer Fee
A clean solar loan (market rate, verified no dealer fee markup) at 7% APR over 12 years:
- Net system cost after ITC: $17,500
- Monthly payment: ~$192
- Total interest paid over 12 years: ~$6,100
- Total financing cost: $23,600
- 10-year cumulative utility savings: $23,200
- Net 10-year position: â$400 (effectively break-even at year 10, profitable from year 11)
The arithmetic is tight. Clean financing is viable because the system continues generating beyond the loan termâyears 12 through 25 are pure return.
Get the Buyer's Guide Before You Decide
The Solar Buyer's Guide covers all five financing scenarios with worked examples and shows you exactly which purchase path matches your financial situation. Get the Buyer's Guide â
Scenario 4: Financed with Dealer Fee (The Warning)
A common solar loan product with a 25% dealer fee rolled into principal at a nominal 2.99% APR:
- Cash system price: $25,000
- Dealer fee (25%): $6,250
- Total financed: $31,250
- Effective APR (true): ~17%
- Total interest paid over 12 years: ~$18,800
- Total cost of financing: $50,050
- Utility savings minus system components: in the negative by year 10
This is the scenario where solar "isn't worth it"âbut the cause is the financing product, not the technology. The solar system itself is generating the same value as in every other scenario. The financing is extracting more than the system produces.
Scenario 5: Leased System (The Worst Case)
With a $120/month lease at 2.9% annual escalator, over 20 years:
- Total lease payments: $38,800
- Ownership at end of lease: None
- Financial return: Negative unless the monthly payment is consistently and significantly below your utility billâwhich the escalator clause erodes over time
What Determines Your Scenario
The ROI scenario you land in is almost entirely determined by one decision: how you fund the system. The hardware, the installation, and the utility savings are roughly equivalent across scenarios 1 through 4. The financing structure is what separates a 189% ROI from a 51% ROI.
Note that the scenarios above use the cash system price â they do not include the hidden infrastructure costs that frequently add 15% to 25% to a first-draft quote. Adjust your net cost input accordingly before running your real model.
FAQ
Is solar worth it without net metering?
For off-grid systems, net metering is irrelevantâyou have no grid connection to sell excess power back to. For grid-tied systems without net metering credits, the economics shift depending on how much of your solar production you consume directly versus export at reduced rates. A battery bank that captures daytime excess for evening use restores the financial viability of solar in markets where net metering has been reduced or eliminated.
Should I wait for solar prices to fall further before buying?
Panel prices have declined 90% over the past 15 years and are now in the range of $0.20 to $0.30 per watt. The remaining cost reduction potential is modest. Meanwhile, every year of waiting adds one year of utility rate escalation at 3.5% to 6% annually. For most homeowners, the utility cost of waiting exceeds the component cost savings from waiting.
What is the minimum solar system size that makes financial sense?
At current component prices, systems below approximately 3kW struggle on pure ROI metrics because fixed costs (permits, interconnection, engineering) don't scale proportionally. Systems above 5kW in good solar resource locations consistently deliver positive ROI across financing scenarios 1 through 3. Size your system for your actual loadâdon't let ROI calculations push you into an undersized system that doesn't meet your energy needs.
How does location affect solar ROI?
Location affects both annual production (peak sun hours) and utility rates. Arizona, Texas, and Florida produce high annual kWh output due to sun hours, but utility rates were historically moderate (this is changing). The Northeast and Pacific Northwest have fewer sun hours but higher utility rates, which partially compensates in the ROI model. The Solar ROI Calculator applies location-specific sun hour data to your calculation automatically.
The question isn't whether solar is worth it. It's how you make it worth it.
Every scenario in this analysis except Scenarios 4 and 5 produces a positive 10-year return. The system works. The investment math works. The question is avoiding the financing structures that extract more value than the system generates.
Buy the system. Buy it right. Fund it the right way. The ROI follows. For a step-by-step interactive version of this analysis with your specific inputs, the Solar Payback Calculator runs the full year-by-year model and shows your break-even year on a single dashboard.
My system crossed the $38,000 in lifetime savings threshold last September. I track it in a spreadsheet that started with a lot of question marks and now has a lot of definitive dollar amounts. The calculation is not complicatedâit just requires the honest inputs. Run the Solar ROI Calculator with your real cost, your real financing, and your real utility rate. Then make your decision from that number.