Real numbers for your home
For one Andover family, the gap between two paths was about $400,000. We’ll run the same honest math for your house — free, on a shared screen.
The Situation
A family of four just bought a 34-year-old colonial in Andover. The roof is due. The oil furnace is original to the house. They’re replacing one car now and another in six years.
The question isn’t whether to spend the money — they’re spending it either way. It’s which set of choices leaves them better off in 10, 20, and 30 years.
The house
Two Paths Forward
Both families buy the same roof and the same two cars. The real difference is what powers the home — and the cars.
The 30-Year Result
After year 9, every winter widens the gap — oil, gas, and electricity all keep climbing, while the solar and heat pump keep working.
Go Deeper
The full case study has the interactive 30-year calculator, the Massachusetts incentive stack, and the complete year-by-year breakdown. Drag the sliders, change the energy prices, and watch the math move.
Why Trust These Numbers
We’re a newer company on purpose — built by people who’d rather show you the spreadsheet than push a product. Every number here is modeled the way an engineer would, at real Massachusetts prices.
Every assumption is on the page — rates, escalation, incentives, equipment. Nothing hidden, nothing rounded in our favor.
If the math says hold off, that’s what we say. We’re fine telling you “not yet” — that’s how you know the rest is honest.
Nearly two decades in renewable energy behind every recommendation — not a call center reading a script.
Your house. Your numbers.
Book a free remote consult and we’ll build a 30-year projection for your house — your roof, your heat, your bills — on a shared screen, together.
Book your free consultA screenshare video call where we walk through the numbers together. About 45 minutes. No in-home visit. No obligation.
How we built these numbers: Path A models a 25 kW solar array (about 27,500 kWh/year, degrading 0.5%/year), a 27 kWh battery, and a cold-climate heat pump replacing roughly 900 gallons of heating oil a year. Massachusetts SMART, MassSave heat-pump and battery rebates, ConnectedSolutions, and the MA solar credit are included. Electricity rises 3%/year, heating oil 4%/year, gasoline 2%/year. Both paths include the same two car purchases, which cancel out in the comparison. These are estimates for illustration only — not financial advice. Your real numbers depend on your home, energy use, utility rates, and current incentives, and programs can change.