Solar Panels vs the Grid
Solar asks for a big check today and then sells you most of your power at a fixed, near-zero rate for decades. The grid asks for nothing upfront and then bills you every month — at a price that tends to climb year after year. The real question is whether the system ever pays back its cost, and how far ahead you end up after it does. That depends entirely on your system price, incentive, bill, and how fast your utility raises rates.
Your numbers
This isolates the payback question: net system price plus the bit of your bill solar doesn't cover, against paying the full, rising grid bill. It assumes you own the system (cash, not a loan), models a flat panel output, and excludes financing interest, resale/home-value effects, and net-metering or SREC credits — see the notes below. Enter your real quote and local bill for the truest answer.
Go solar
A big cost upfront (less the credit), then most of your power at a fixed, near-zero rate for the life of the system.
Total cost over 25 years
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Net cost after credit
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Break-even year
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Lifetime net savings
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Year-1 offset savings
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Stay on grid
Nothing upfront, then the full electric bill every month — at a price that tends to climb year after year.
Total cost over 25 years
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Year-1 electricity bill
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Final-year electricity bill
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Total paid to the utility
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Cumulative cost over time
How solar payback works
Solar flips the usual deal with your utility. Instead of paying a monthly bill forever, you pay most of the cost once, upfront — and then your panels make power at a fixed, near-zero running cost for 25 years or more. The catch is that big upfront number: a system can cost as much as a used car, and you don't see a dime of it back on day one.
So the whole game is payback. Every month, the bill you no longer pay the utility quietly chips away at the system's cost. The break-even year is the moment those avoided bills add up to what you spent — after that, every year is money in your pocket that staying on the grid would have spent. This calculator finds that crossing point and then shows how far ahead you end up by the end of the projection.
Why the utility rate increase matters
This is the number people underestimate, and it's the one that does the heavy lifting. Your solar cost is mostly fixed the day you buy. The grid's cost is not — utilities raise rates most years, and those increases compound. A bill rising 3% a year doesn't just grow 3%; over 25 years it roughly doubles.
That's what makes solar win over the long run. You're not just comparing today's bill to today's panels — you're comparing a flat cost to a rising one. The gap widens every single year, which is why a system that looks like a slow payback in year five can pull dramatically ahead by year twenty. Set the rate-increase field to your utility's real history (look at a few old bills) and watch how much it moves the answer.
What this leaves out
To keep the payback math honest and legible, several real-world factors aren't modeled here — most of them make solar look slightly better on paper than this page shows, and a couple make it look worse:
- Loan interest. This assumes you pay cash (or that the credit covers your down payment). If you finance the system, interest is a real added cost that pushes the break-even year later — sometimes by several years.
- Panel degradation. Output drifts down roughly 0.5% a year, so the bill you offset shrinks slightly over time. We model flat output, which makes the long-run savings here a touch optimistic.
- Home-value bump. Studies consistently find owned solar raises a home's sale price. That's upside this calculator ignores entirely.
- Net metering & SRECs. What your utility pays for the surplus you export, and any renewable-credit market, can meaningfully sweeten the deal — and the rules vary wildly by location.
- Roof replacement. If your roof needs work within the system's life, removing and reinstalling panels is a real cost worth pricing in separately.
About the incentive
The incentive is the most volatile number on this page. The US federal 30% Residential Clean Energy Credit ended for systems placed in service after December 31, 2025 — a homeowner-owned system installed today receives no federal tax credit. Leased and PPA systems can still benefit indirectly through the separate commercial credit, and some states and utilities offer their own rebates; others offer nothing. We treat it as a plain input for exactly that reason. Verify your own eligibility and the current rate before you trust any total here, and set the field to what you'll actually receive — not the headline number.
FAQ
Does this include a solar loan?
No — it assumes you own the system outright, paid in cash (or that the tax credit effectively covers your down payment). Financing changes the picture: a loan adds interest on top of the system price, which raises the real cost and pushes the break-even year later, sometimes by several years. If you're financing, treat the totals here as the best case and add your expected interest separately. The flip side is that a low-rate loan can still beat a fast-rising grid bill — it just doesn't pay back as quickly as cash does.
What about panel degradation?
Solar panels lose roughly 0.5% of their output per year, so 25 years in, a system makes around 85–90% of what it did when new. This calculator models a flat output for simplicity, which makes the later-year savings here slightly optimistic. In practice the effect is gradual and modest, and it's usually swamped by the rising-grid-price effect working in solar's favor — but if you want a conservative number, shave a little off the lifetime net savings shown above.
Does solar add home value?
Studies generally say yes — owned solar (not leased) tends to raise a home's sale price, often by a meaningful chunk of what the system cost. This calculator does not model that at all, so it's pure upside not captured in the totals: if you sell partway through the projection, a buyer is often willing to pay extra for a paid-off system that comes with cheap power. Leased systems are a different story and can actually complicate a sale, so this only applies to systems you own.