Solar Panel Cost Calculator 2026
Enter your system size, region and electricity rate to instantly see your annual savings, payback period and 25-year profit projection. Includes the IRA 30 % federal tax credit for US homeowners and accounts for battery storage self-consumption.
☀️ Your System Details
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Annual Production & Self-Consumption
Energy Split (Year 1)
⚡ Pro Tip: Size it right
Aim for a system that covers 80–100 % of your annual usage. Going bigger earns more export income but may have diminishing returns if your utility pays less for excess. Adding a battery doubles self-sufficiency — ideal if your utility has reduced net metering rates. The IRA 30 % tax credit applies to batteries too when co-installed with solar.
Solar Panel Costs in the US and Australia (2026)
Solar panel prices have dropped over 90 % since 2010, making rooftop solar one of the best financial decisions a homeowner can make. Here’s what to expect by market.
United States: System Cost by Size
| System size | Gross cost | After IRA (30 %) | Typical home size |
|---|---|---|---|
| 4 kWp | $12,800 | $8,960 | Small home / low usage |
| 8 kWp | $25,600 | $17,920 | Medium home (2,000 sq ft) |
| 12 kWp | $38,400 | $26,880 | Large home / EV charger |
| 20 kWp | $64,000 | $44,800 | Large home + pool + EV |
Based on $3,200/kWp installed average. Prices vary by installer and region.
Australia: System Cost by Size
| System size | After STC rebate (AUD) | Annual yield (QLD) | Payback (QLD) |
|---|---|---|---|
| 6.6 kWp | $4,500–$7,500 | 12,800 kWh | 3–5 years |
| 10 kWp | $7,000–$11,000 | 19,500 kWh | 4–6 years |
| 13.2 kWp | $9,000–$14,000 | 25,700 kWh | 4–7 years |
Solar Resource by Region: How Much Can You Produce?
The amount of sunlight available — measured as peak sun hours or specific yield (kWh/kWp/year) — varies dramatically by location and is the biggest driver of your system’s financial performance.
| Region | Specific yield | 10 kWp annual output | Relative performance |
|---|---|---|---|
| US – Southwest (AZ, NM) | 2,000 kWh/kWp | 20,000 kWh | Excellent |
| US – California | 1,850 kWh/kWp | 18,500 kWh | Excellent |
| AU – Queensland | 1,950 kWh/kWp | 19,500 kWh | Excellent |
| AU – South Australia | 1,750 kWh/kWp | 17,500 kWh | Very good |
| US – Southeast (FL, TX) | 1,650 kWh/kWp | 16,500 kWh | Very good |
| AU – New South Wales | 1,600 kWh/kWp | 16,000 kWh | Very good |
| US – Midwest | 1,350 kWh/kWp | 13,500 kWh | Good |
| US – Northeast | 1,250 kWh/kWp | 12,500 kWh | Good |
| AU – Victoria | 1,450 kWh/kWp | 14,500 kWh | Good |
| US – Pacific NW | 1,200 kWh/kWp | 12,000 kWh | Fair |
IRA 30% Solar Tax Credit: Full Explanation
The Inflation Reduction Act (IRA) extended and expanded the federal Investment Tax Credit (ITC) to 30 % through 2032, dropping to 26 % in 2033 and 22 % in 2034 before expiring for residential projects.
IRA Tax Credit: Key Facts
- 30 % of total system cost — including panels, inverter, mounting, wiring and battery storage
- Claimed on IRS Form 5695 (Schedule A not required)
- Applied to your federal income tax liability for the year of installation
- Unused credit rolls over to the following tax year if your tax bill is less than the credit
- Applies to new and existing homes — primary residence, vacation homes and rental properties (with caveats)
- No income cap or system size limit
IRA Example: 10 kWp System in California
| Gross system cost | $32,000 |
| Battery storage (10 kWh) | $8,000 |
| Total eligible cost | $40,000 |
| IRA 30 % credit | − $12,000 |
| Net cost to homeowner | $28,000 |
Should You Add a Battery? (2026 Analysis)
Battery economics have shifted significantly since California’s NEM 3.0 cut retail-rate net metering in 2023. Under NEM 3.0, utilities pay as little as 5–8 ¢/kWh for exported solar instead of the previous 30 ¢/kWh retail rate. This makes self-consumption — and therefore batteries — far more valuable.
Battery makes sense when:
- Export / net metering rate is below your retail rate
- You want backup power during outages
- You have Time-of-Use (TOU) rates with peak pricing 4–9 pm
- You charge an EV at night (use cheap overnight rates + stored solar)
Battery less critical when:
- Full retail net metering applies (pre-NEM 3.0 CA, most AU states)
- System is small (< 5 kWp) and fully self-consumed
- Budget is tight — the IRA credit still applies to a later battery add-on
Pro Tip: Battery costs & IRA
A 10 kWh battery (e.g. Tesla Powerwall 3) costs ~$8,000–$12,000 installed. With the IRA 30 % credit, net cost is ~$5,600–$8,400. The battery also qualifies for the credit even if installed after the solar panels — as long as it’s charged primarily from the PV system (≥ 3 kWh capacity, ≥ 3 kWp system). This gives you flexibility to add storage later.
Frequently Asked Questions
How much does a solar panel system cost in the US?↓
A typical residential solar system costs $15,000–$30,000 before incentives (4–10 kWp). After the IRA 30% federal tax credit the net cost drops to $10,500–$21,000. State and utility rebates can reduce this further. Cost per watt has fallen from $8 in 2010 to around $3.00–$3.50 today.
What is the IRA 30% solar tax credit?↓
The Inflation Reduction Act (IRA) provides a 30% federal investment tax credit (ITC) for residential solar systems installed through 2032. It applies to the full system cost including battery storage, and you claim it on IRS Form 5695. It reduces your income tax bill dollar-for-dollar — not just a deduction.
How much will solar panels save me per year?↓
A typical 10 kWp system in California (1,850 kWh/kWp) produces about 17,000 kWh/year. At 30 ¢/kWh retail electricity, the annual saving is roughly $4,000–$5,000 including net metering export income. In Arizona with higher irradiance, savings are even higher. Use our calculator above for your exact numbers.
What is the payback period for solar panels?↓
With the IRA credit, most residential systems in the Sun Belt pay back in 5–9 years, and in the Northeast in 8–13 years. Without incentives, add 3–4 years. After payback, panels typically run 20–30 more years at near-zero fuel cost.
How much does solar cost in Australia?↓
A 6.6 kWp system costs AUD $5,000–$9,000 installed after the STC (Small-scale Technology Certificate) rebate. Per kWp costs around AUD $900–1,400 net. Queensland and South Australia have excellent solar resources — payback periods of 4–6 years are common.
Do I need a battery with solar panels?↓
Not necessarily. If your utility offers good net metering rates (paying close to retail for exported power), a battery adds $6,000–$12,000 for limited financial benefit. However, if net metering has been cut — as in many California NEM 3.0 markets — a battery dramatically improves self-sufficiency and financial returns. The calculator shows the difference.
What size solar system do I need?↓
Divide your annual kWh consumption by the specific yield for your region. Example: 12,000 kWh ÷ 1,850 kWh/kWp (California) = 6.5 kWp. Going slightly larger is usually worthwhile since marginal costs are low and you can export surplus. A 10 kWp system suits most US homes consuming 10,000–14,000 kWh/year.
How long do solar panels last?↓
Most quality panels carry a 25-year performance warranty guaranteeing at least 80–85% of original output. Actual lifespan is typically 30–40 years. Degradation is about 0.5% per year — a panel rated 400 W produces ~380 W after 10 years. Inverters typically last 10–15 years and may need replacement.