What is a good solar payback period?

There is no universal number, and anyone quoting one is guessing about your life rather than your roof. Compare simple payback to how long you will own the house. This model’s default 12 kW at $2.58/W, 18.44¢/kWh, 1,400 kWh/kW/yr and 70% self-use returns about 14.3 years with a 0% federal credit.

Why is the federal credit set to 0%?

§25D is not available for property placed in service after 31 December 2025. Leaving 30% in the model would invent a saving you cannot claim. If your system was placed in service by that date, set it to 30 and the payback falls proportionally, from 14.3 years to 10.0 at the defaults.

Why does the model use self-consumption instead of all production?

Because exported kilowatt-hours are usually credited below retail. Valuing every kWh at full retail overstates savings under net billing and buyback tariffs. Dropping self-consumption from 70% to 40% moves payback from 14.3 years to 25.0, which shows how much this single assumption carries.

Is simple payback the same as return on investment?

No, and the difference matters. Simple payback stops asking questions at the break-even year, so it ignores everything a system earns afterwards and ignores costs that arrive later, such as an inverter replacement. It is a screening tool for comparing options, not a verdict on whether solar is a good investment.

Why does your payback calculator disagree with your savings calculator?

Because they use different denominators, and both are correct. This tool values 70% self-consumption of what the array generates. The savings calculator values an 85% offset of what the house consumes. Those are different quantities, so the same house can return 14.3 years here and about 11.8 there. Use this one when you know your system size and price; use that one when you know your usage and bill.

Should I use my energy rate or my total rate?

Your total, blended rate: the whole bill divided by the whole kilowatt-hours. Delivery charges are frequently the larger half of a residential bill, and solar offsets the kilowatt-hours that carry both. Using the supply line alone can make payback look years worse than it is.

Does a battery improve payback?

It changes two things in opposite directions. It raises self-consumption, which shortens payback, and it raises net cost, which lengthens it. This model has no battery input, so the honest approach is to run it twice: once with the array alone, once with the battery in the price and a higher self-consumption figure, and compare.

What is not included in this calculation?

Discounting, degradation, utility rate inflation, maintenance, inverter replacement, export credit, and any cost outside the price per watt you entered, roof work, a main panel upgrade, trenching for a ground mount. Every one of those is real. Simple payback is the number you can check by hand, which is its whole purpose.

My payback came out over 25 years. Is the calculator wrong?

Probably not. It is telling you that at these inputs the system does not recover its cost within its own working life. Check three things first: that the rate is your blended rate, that self-consumption is not set unrealistically low, and that the price per watt reflects a real quote rather than a placeholder. If all three are right, the answer is the answer.

HyreSolar tools

Solar payback calculator

Years of bill savings to recover the net cost, from system size, price per watt, your rate and how much of the output you use at home.

Checked September 3, 2026. Data as of August 6, 2026. HyreSolar sells and installs nothing.

This solar payback calculator gives an estimate from your own numbers in under a minute, with every assumption listed under the result.

Simple payback is the net cost divided by the first year’s bill savings. With the example inputs, a 12 kW system at $2.58/W on an 18.44¢ rate pays back in 14.3 years.

At 32¢ it is 8.2 years; at 11¢, 23.9 years. The federal credit is set to 0% because §25D ended for systems placed in service after 2025.

Payback answers one question: how many years of bill savings it takes to recover what you paid.

It is the simplest test of whether a quote makes financial sense, and it is easy to distort.

A shorter payback can come from a lower price, a higher electricity rate, more sun, or an assumption that every kilowatt-hour the panels make replaces one you would have bought at full price.

That last one, self-consumption, is an input here because under net billing exported power is worth much less than imported power.

The federal credit is set to zero. For years, solar payback figures subtracted 30% of the cost before dividing, and many still do.

§25D does not apply to systems placed in service after 31 December 2025, so a payback period that uses it is several years shorter than the one you will actually see.

If a proposal quotes a payback, check whether it assumed the credit, and rerun it here with the proposal’s own price and production.

Simple payback ignores rising electricity prices, panel degradation, financing costs and the inverter you will probably replace once.

Those roughly offset in some cases and not in others, so read the result as a guide, not a guarantee.

As a rule of thumb, a payback well inside the panel warranty (often 25 years) leaves room for surprises; one close to it does not.

When the number looks right, send the result to an installer with the form underneath and ask them to beat it in writing.

Cash payback model

Change any input. Default credit is 0%.

Example values The filled-in numbers are an example, not your home. Type over them with your own.

— Simple payback

— Net cost

— Year-1 savings

— On-site kWh modeled

How this result was worked out

Working it out from the numbers above.

Simple payback, not discounted. Default §25D is 0%.

A quote’s $/W and a PVWatts yield beat these defaults. HyreSolar does not sell systems.

How to read the number you just got

Simple payback is the year in which cumulative bill savings equal what you paid. It is deliberately crude. It does not discount future money, it assumes your rate and your production hold, and it stops asking questions the moment the two numbers meet. Its virtue is that you can check it in your head.

The comparison that matters is against how long you will own the house, not against some universal target.

A 14-year payback is excellent if you are staying 30 years and irrelevant if you are moving in four.

Nobody can tell you what a good payback is without knowing that, which is why we will not print a target here.

A payback longer than the equipment warranty is a warning. If the number comes back above roughly 25 years, the model is telling you the system does not pay for itself within its own working life at these inputs. That is a real answer, not a broken calculator.

Under 10 years: Usually a high electricity rate doing the work, sometimes a genuinely cheap installation. Check the rate you entered is your blended rate and not just the energy line.
10 to 18 years: The ordinary range at 2026 prices and average rates. Whether it is good depends almost entirely on how long you are staying.
Over 20 years: Something is stretched: a low rate, a high price per watt, or self-consumption well under half. Find out which before treating the system as a bad idea.

Where to find each number

Where each input comes from, so nothing is a guess.

1. Enter the system size in kW DC

Use the DC nameplate figure, which is the number of panels multiplied by their wattage. A 12 kW system is roughly 30 panels at 400 W.

Where to find it: The top line of any proposal, usually written as "system size" or "kW DC". If you only have a panel count and a wattage, our panel count calculator converts between them.

2. Enter your installed price per watt

Total contract price divided by system watts. This is the only fair way to compare two quotes for different sized systems.

Where to find it: Divide the quoted total by the system size in watts. A $30,960 quote on a 12 kW system is $2.58/W. Our proposal analyzer does this and unwinds a dealer fee at the same time.

3. Enter your blended retail rate in cents

Not the energy charge alone. Take the full bill and divide by the kilowatt-hours it covers, so delivery, supply and fixed charges are all inside the number.

Where to find it: Your utility bill. Total amount due divided by total kWh. Delivery is frequently the larger half, which is why the energy line alone understates what a kWh actually costs you.

4. Set specific yield if you know it

Annual kWh generated per kW of DC capacity. The 1,400 default is a US planning mid-band, not a figure for your roof.

Where to find it: Run your address through NREL PVWatts and divide its annual kWh by your system size in kW. That is the single biggest accuracy improvement available to you here.

5. Set self-consumption honestly

The share of what you generate that you use on site rather than export. This is the input people get most wrong, and it moves the answer more than almost anything else.

Where to find it: If you are home during the day, have a battery, or run air conditioning on summer afternoons, it is higher. If the house is empty from eight to six, it is lower. Without a battery, 30 to 50 percent is common.

6. Leave the federal credit at 0 unless you qualify

The residential credit under §25D is not available for property placed in service after 31 December 2025. Leaving 30% in the model invents a saving you cannot claim.

Where to find it: Your placed-in-service date, not your contract date. See what the §25D expiry actually changed.

How the calculator works it out

1
Build a net cost
Size × $/W, then subtract only a credit you actually qualify for. Default credit is 0%.
2
Estimate on-site kWh
Size × specific yield × self-consumption. Yield is not PVWatts unless you replace it with PVWatts.
3
Value those kWh at retail
This ignores export credit below retail and fixed charges.
4
Divide
Net cost ÷ year-1 savings. That is simple payback.

The formula, in full. gross = kW × 1000 × $/W. net = gross × (1 − credit). annual kWh = kW × yield × self-use. annual saving = annual kWh × rate ÷ 100. years = net ÷ annual saving.

A worked example, start to finish

A 12 kW system in a house on the national average residential rate, priced at the 2026 marketplace survey midpoint, with no federal credit because the system is placed in service in 2026.

Step	Value
System size	12 kW DC
Installed price	$2.58 / W
Gross cost	$30,960
Federal credit	0%, §25D closed
Specific yield	1,400 kWh / kW / yr
Annual production	16,800 kWh
Self-consumption	70%
Valued on site	11,760 kWh / yr
Blended rate	18.44 ¢ / kWh
Result	14.3 years

Net cost $30,960 recovered by $2,169 of avoided electricity a year. Note what is not in that: the 5,040 kWh exported each year earns whatever the export rate is, and at most tariffs that is well below retail. If your utility pays a meaningful export credit, real payback is shorter than this model says.

How the answer moves

The same 12 kW system, one input changed at a time. Every figure is computed by the calculator on this page.

Change	Year-1 saving	Simple payback	Against the 14.3-year base
Base case18.44¢, $2.58/W, 70% self-use	$2,169	14.3 years	Reference
Rate 11¢ instead of 18.44¢	$1,294	23.9 years	9.6 years worse
Rate 32¢ instead of 18.44¢	$3,763	8.2 years	6.1 years better
Price $3.50/W instead of $2.58	$2,169	19.4 years	5.1 years worse
Price $2.00/W instead of $2.58	$2,169	11.1 years	3.2 years better
Self-consumption 40% not 70%	$1,239	25.0 years	10.7 years worse
Self-consumption 100% not 70%	$3,098	10.0 years	4.3 years better
Yield 1,000 not 1,400	$1,549	20.0 years	5.7 years worse
Yield 1,800 not 1,400	$2,788	11.1 years	3.2 years better

Read the two extremes: the electricity rate swings the answer by 15.7 years across the range shown, and self-consumption by 15 years. Price per watt, the thing you negotiate hardest, swings it by 8.3.

What moves this number most

Ranked, largest first. A proposal can change any of these without saying anything untrue, so check these inputs first.

1. Your electricity rate

The largest single driver, and the one nobody controls. Moving from 11¢ to 32¢ takes payback from 23.9 years to 8.2. The same equipment on the same roof is a different investment in two states. Compare rates in our bill-by-state analysis.

2. Self-consumption

Almost as powerful, and far more often wrong in a proposal. Dropping from 70% to 40% adds 10.7 years. It matters because exported kilowatt-hours are usually credited below retail, so a model that values every kWh at retail flatters the result.

3. Specific yield

Where the roof actually is, which way it faces and what shades it. The 1,400 default is a national mid-band; a shaded north-facing plane will not reach it. See what shade does to output.

4. Installed price per watt

The input you negotiate and the third most powerful. Worth pushing on, but note that beating your installer down by $0.58/W buys you 3.2 years while living in a 32¢ state buys you 6.1.

5. The federal credit, if you still qualify

A 30% credit cuts net cost and payback by 30% proportionally. For systems placed in service after 31 December 2025 it is $0, which is why this model defaults to zero.

6. What is deliberately absent

Degradation, rate inflation, discounting, maintenance and inverter replacement are all outside simple payback. Each of those pushes the real answer in a different direction, which is the honest reason simple payback is a screening tool and not a verdict.

Common mistakes with this calculation

Using the energy charge as your rate
Delivery is frequently the larger half of a residential bill. Entering only the supply rate can understate your true cost per kilowatt-hour by a wide margin and makes payback look far worse than it is. Divide the whole bill by the whole kWh.
Leaving the federal credit at 30%
It is the default on most calculators elsewhere and it is wrong for a 2026 placed-in-service date. A 30% credit that does not exist makes a 14.3-year payback look like 10.0.
Assuming 100% self-consumption
Valuing every generated kilowatt-hour at full retail is the most common way a proposal overstates savings. Unless you have storage or are home all day, a large share is exported and credited at a lower rate.
Comparing payback to a national average instead of your own timeline
There is no universal good number. Compare it to how long you intend to own the house, and if you may sell before then read what solar does to resale value.
Treating $/W as complete
A price per watt only includes what the contract includes. Roof work, a main panel upgrade, trenching or a battery may sit outside it, and each one lengthens real payback without appearing in this model.
Reading simple payback as return on investment
It is not. It ignores everything after the break-even year, so it systematically undersells a system that runs for 25 years and oversells one that will need an inverter at year 12.

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What this calculator leaves out

The result is a planning estimate. A real proposal accounts for these; this page does not.

Not discounted.
A dollar saved in year 20 is treated as a dollar saved today.
Export below retail is ignored entirely.
Only self-consumed kilowatt-hours are valued.
Degradation, rate inflation, maintenance and inverter replacement are all outside the model.
Dealer fees, panel upgrades and roof work are not in $/W unless you put them there.
§25D is $0 for systems placed in service after 31 December 2025.

The research behind these numbers

What the §25D expiry changedWhy the federal credit in this model defaults to zero, and which placed-in-service dates still qualify.Read the research Your first bill after solarOur own measurement: delivery is 53.2% of the residential bill across 14.7 million customers. This is why the blended rate matters.Read the research Net metering, net billing and buybackWhat happens to the kilowatt-hours you export, and why self-consumption is the input that carries the model.Read the research Panel degradation, measuredThe output loss this model deliberately ignores, and why the warranted rate sits inside the measurement tolerance.Read the research Electricity bills by stateWhere your rate sits, computed from EIA-861. The largest single driver of the number above.Read the research Shade and solar outputWhat actually sets specific yield, and the 80% threshold two independent sources both land on.Read the research

Questions this calculator answers

What is a good solar payback period?: There is no universal number, and anyone quoting one is guessing about your life rather than your roof. Compare simple payback to how long you will own the house. This model’s default 12 kW at $2.58/W, 18.44¢/kWh, 1,400 kWh/kW/yr and 70% self-use returns about 14.3 years with a 0% federal credit.
Why is the federal credit set to 0%?: §25D is not available for property placed in service after 31 December 2025. Leaving 30% in the model would invent a saving you cannot claim. If your system was placed in service by that date, set it to 30 and the payback falls proportionally, from 14.3 years to 10.0 at the defaults.
What is specific yield and where do I get mine?: Annual kilowatt-hours per kilowatt of DC capacity. The 1,400 default is a US planning mid-band. For your actual roof, run your address through NREL PVWatts and divide its annual kWh by your system size. Moving from 1,000 to 1,800 changes payback from 20.0 years to 11.1, so this is worth doing properly.
Why does the model use self-consumption instead of all production?: Because exported kilowatt-hours are usually credited below retail. Valuing every kWh at full retail overstates savings under net billing and buyback tariffs. Dropping self-consumption from 70% to 40% moves payback from 14.3 years to 25.0, which shows how much this single assumption carries.
Is simple payback the same as return on investment?: No, and the difference matters. Simple payback stops asking questions at the break-even year, so it ignores everything a system earns afterwards and ignores costs that arrive later, such as an inverter replacement. It is a screening tool for comparing options, not a verdict on whether solar is a good investment.
Why does your payback calculator disagree with your savings calculator?: Because they use different denominators, and both are correct. This tool values 70% self-consumption of what the array generates. The savings calculator values an 85% offset of what the house consumes.; Those are different quantities, so the same house can return 14.3 years here and about 11.8 there. Use this one when you know your system size and price; use that one when you know your usage and bill.
Should I use my energy rate or my total rate?: Your total, blended rate: the whole bill divided by the whole kilowatt-hours. Delivery charges are frequently the larger half of a residential bill, and solar offsets the kilowatt-hours that carry both. Using the supply line alone can make payback look years worse than it is.
Does a battery improve payback?: It changes two things in opposite directions. It raises self-consumption, which shortens payback, and it raises net cost, which lengthens it. This model has no battery input, so the honest approach is to run it twice: once with the array alone, once with the battery in the price and a higher self-consumption figure, and compare.
What is not included in this calculation?: Discounting, degradation, utility rate inflation, maintenance, inverter replacement, export credit, and any cost outside the price per watt you entered, roof work, a main panel upgrade, trenching for a ground mount. Every one of those is real. Simple payback is the number you can check by hand, which is its whole purpose.
My payback came out over 25 years. Is the calculator wrong?: Probably not. It is telling you that at these inputs the system does not recover its cost within its own working life.; Check three things first: that the rate is your blended rate, that self-consumption is not set unrealistically low, and that the price per watt reflects a real quote rather than a placeholder. If all three are right, the answer is the answer.

Sources and methodology

Figures dated August 6, 2026. Last reviewed September 3, 2026 by the HyreSolar research desk, which writes and checks every tool on this site.

Electric Power Monthly, Table 5.6.A (EIA, retrieved August 6, 2026). Default 18.44¢/kWh national residential average, May 2026 data.
Residential Clean Energy Credit (§25D) (IRS, retrieved August 11, 2026). Basis for the 0% default federal credit.
U.S. Solar Photovoltaic System Cost Benchmark (NREL, retrieved August 16, 2026). $/W is a survey input you should replace with a real quote.
PVWatts Calculator (NREL, retrieved August 16, 2026). The right source for specific yield on your own roof.

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