ElectrifyCost

Free tool

Project Simulator

Planning more than one electrification upgrade? Add each project to your plan, pick a starting scenario — or configure it exactly in its full calculator — and we roll 10,000 Monte Carlo scenarios for an honest combined budget: the median total plus a safer-budget figure you can plan around, instead of just adding up the low and high estimates.

Built by Martin Lashgari, Ph.D., P.E., PMP — a licensed structural engineer · Last reviewed 2026-07-04 · A planning simulation, not a quote or bid.

National average — add a ZIP for local labor pricing

Your project plan

Nothing here yet — add projects from the catalog below, start from a quick bundle, or configure one in its calculator first.

Add one or more projects to roll the simulation.

Add projects

32 calculators · 5 categories
Quick start:
HVAC & heating8
Heat pump (central)
$7,300–$20,200
Mini-split / ductless
$9,300–$15,900
Geothermal heat pump
$20,300–$31,800
AC replacement
$8,650–$14,400
Gas furnace replacement
$4,350–$8,350
Boiler replacement
$8,200–$15,300
Ductwork install
$3,750–$8,700
Smart thermostat
$375–$925
Solar & power7
Solar panels
$20,000–$36,000
Off-grid solar system
$23,000–$51,200
Home battery
$14,100–$22,800
Generator backup
$7,250–$17,400
Electrical panel upgrade
$1,550–$5,100
Smart electrical panel
$2,800–$5,600
Sump pump + battery backup
$900–$2,500
EV charging1
EV charger install
$875–$3,700
Water heating7
Tank water heater
$1,275–$3,000
Heat pump water heater
$2,100–$6,200
Tankless water heater
$3,400–$6,800
Hot water recirculation pump
$500–$1,450
Water softener + filtration
$1,800–$4,800
Pool heat pump
$4,400–$8,700
Hot tub heat pump
$2,700–$5,500
Home improvements9
Insulation
$7,600–$16,400
Air sealing
$800–$2,000
Window replacement
$3,150–$6,300
Door replacement
$1,500–$3,600
Roof replacement
$12,200–$23,900
Home energy audit
$250–$650
Induction stove
$1,450–$5,000
Heat pump dryer
$1,400–$3,100
Wood / pellet stove
$3,400–$8,800

Why a combined estimate isn’t just low + low and high + high

Add up the low ends of five projects and you get a best case that almost never happens — every job would have to land at its cheapest at the same time. Add up the high ends and you get a worst case that’s just as unlikely. The honest answer sits in between, and it’s tighter than the naive sum: across many projects, some run high while others run low, so the combined total clusters toward the middle (the portfolio effect).

But the projects aren’t fully independent, either. A hot regional labor market or an equipment price spike pushes several of your projects up at once. Ignoring that correlation would understate your risk and give a false sense of confidence — so the simulator links the projects through a shared market factor. The result is a distribution: a most-likely total, and a safer-budget (P90) figure you have about a 9-in-10 chance of coming in under.

Method & sources

Each project’s installed-cost band comes from its ElectrifyCost calculator (at a small / typical / large scale you choose, adjusted for your state’s labor market). Per trial, each project’s cost is sampled from a triangular distribution over its band with the mode skewed slightly high (cost overruns skew that way), and all projects are correlated through one shared market factor (implied correlation ≈ 0.5). We run 10,000 trials and read the percentiles off the results.

Real-world surprises (optional) add a right tail: known-but-uncertain extras — a panel upgrade the heat pump needs, knob-and-tube wiring, a utility interconnection delay — are sampled with an approximate probability and a sourced cost range. The odds are reasoned planning estimates; the cost ranges are sourced.

This is an early-planning (AACE Class 5) view made probabilistic — inherently wide, and a specific project can land outside the range. It states the probability of a cost; it is not a quote, bid, or guarantee, and it doesn’t replace your contractor, permit, or inspector. See the full methodology and data sources.

Frequently asked questions

Why is the combined total not just the sum of the low and high estimates?

Adding up every project’s low end gives a best case that almost never happens — every job would have to land at its cheapest at the same time. Adding up the high ends gives an equally unlikely worst case. The honest answer sits in between and is tighter than the naive sum: across many projects, some run high while others run low (the portfolio effect). The simulator rolls 10,000 scenarios to find that combined distribution.

What are the three numbers (Optimistic / Most likely / Safer budget)?

Optimistic is the P10 — you have about a 10% chance of coming in under it. Most likely is the median (P50) — half of the simulated outcomes land under it, half over. Safer budget is the P90 — you have about a 9-in-10 chance of coming in under it, which is the figure to actually plan around.

Does it include rebates or tax credits?

No. The simulation models installed (gross) cost before incentives, because that is where the real line-item uncertainty lives. Rebate and credit eligibility is specific to your state, income, and the program’s status — check each project’s own calculator and the /rebates/ page for what you may qualify for.

What are “real-world surprises”?

Optional cost adders for the things that turn up once work starts — a panel upgrade the heat pump needs, knob-and-tube wiring in an older home, a utility interconnection delay. The cost ranges are sourced; the odds are reasoned planning estimates, not measured rates, and are labeled as approximate.

Estimates are planning ranges, not contractor quotes. The combined simulation states the probability of a cost, not a promised price. It covers known unknowns (the surprises a seasoned installer expects), not black-swan events, and assumes typical projects. Per-project numbers come from the individual ElectrifyCost calculators; verify rebate eligibility on the rebates page before relying on any incentive.