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Solar savings & payback
Your bill, your utility’s export rules and our real pricing — cash, loan, lease and PPA side by side over 25 years.
Your modeled system
Xcel Energy — kWh banking + time-of-useSystem
8.8 kW
21 panels · 1,482 kWh/kW
Installed cost
$24.6k–$28.6k
before incentives
Year-1 savings
$1.6k–$1.6k
77–77% of energy spend
Cash payback
14–16 yrs
97% of usage offset
Monthly production vs. usage
How much of each month your panels cover (kWh)
Your usageSolar production
A typical day, hour by hour
Where each hour’s power comes from
Home usage (kWh)Solar (kWh)Grid import (kWh)
25 years, four ways to pay
Cumulative net savings vs. staying with the utility (midpoint scenario)
CashColorado RENU loan · 7.74% / 20 yrConcert Finance · 8.99% / 25 yrLease / PPA · 3%/yr escalator
| Option | Upfront | Monthly | Payback | IRR | NPV @5% | 25-yr net |
|---|---|---|---|---|---|---|
| Cash | $26,620 | — | 15 yrs | 5.6% | $1,935 | $27,244 |
| Colorado RENU loan · 7.74% / 20 yr | $0 | $221 | — | — | -$4,459 | $882 |
| Concert Finance · 8.99% / 25 yr | $0 | $223 | — | — | -$9,197 | -$13,099 |
| Lease / PPA · 3%/yr escalator | $0 | $125 | — | — | $231 | -$112 |
Your utility’s rules, as modeled
- Exports banked 1:1 as kWh credits under Colorado PUC net metering.
- Time-of-use on-peak 5–9 pm non-holiday weekdays, year-round; on-peak ≈2.7× off-peak (Colorado PUC).
Energy flows (year)
- Usage
- 13,500 kWh
- Solar
- 13,042 kWh
- Used on-site
- 5,725 kWh
- Exported
- 7,316 kWh
- Bought from grid
- 7,775 kWh
- From battery
- 0 kWh
How this model works — assumptions & sources
- Household load follows a typical Front Range hourly and seasonal shape scaled to your annual kWh (edit usage for accuracy; the AI Bill Reader uses your real months).
- Solar production uses NREL PVWatts hourly data for your location when available; otherwise an average-day curve scaled to NREL-modeled Colorado yields (~1,300–1,600 kWh per kW per year).
- Batteries: 90% round-trip efficiency, 20% reserve held for outages; they charge from solar and discharge during peak/demand windows (or whenever solar falls short on flat-rate plans).
- Utility rules are simplified from published tariffs and dated research; items marked ‘reported’ are unverified. We confirm your exact tariff before any proposal.
- Rate growth 2–4%/yr and 0.5%/yr panel degradation; NPV at a 5% discount rate. No federal credit for owned residential systems (ended for installs completed after Dec 31, 2025).
- Colorado’s 10% home-battery income-tax credit applies to the battery’s purchase price (equipment, sales tax, freight — not labor) for tax years through 2026; we estimate it at 60–80% of the installed battery price × 10%.
- Pricing: our installed range of $2.80–$3.25/W; batteries at our quoted prices. Every number here is an estimate, not a quote.
Get honest numbers for your roof
Our Colorado crew looks up your utility’s current rules, models your roof, and tells you straight — including when solar or a battery won’t pay off.