Three ways to keep your house alive when the grid dies — and most companies can only sell you one of them, which is exactly how they'll answer. We're not tied to one answer. Here's the straight case for each, what they cost to live with, and what actually works together today.
Full disclosure, up front: we install batteries and V2H today; generators are next on our roadmap. If a generator is your right answer, we'll say so — even while it's the one thing we can't yet sell you.
| ⛽ Standby generator | 🔋 Home battery | 🚗 Your EV (V2H) | |
|---|---|---|---|
| Runtime | Days to weeks — as long as natural gas or propane flows. The endurance king. | Essentials for 12–24 hours per unit (13.5 kWh); units stack for more. | Days — a typical EV holds 80–130 kWh, five to ten times one home battery. |
| Switchover | Automatic, with a few seconds of gap while it starts. | Instant and seamless — you find out from the app, not the flicker. | Automatic — but the vehicle has to be home and plugged in. |
| Noise & fuel | A running engine outside your window, plus fuel cost while it runs. | Silent, no fuel, no fumes. | Silent. "Refueling" = driving somewhere with power and charging. |
| Value when the grid is UP | Sits idle except a monthly self-test. | Earns daily where plans allow — cheap overnight charging, demand-spike shaving on SEC. See our rates guide. | You already own the battery — it drives you to work. V2H just adds the second job. |
| Upkeep | Annual service required — a generator that isn't serviced doesn't start. | Essentially none. | None beyond the car itself. |
| Typical cost | We'll publish real numbers when our generator program launches — be wary of anyone quoting without a site visit. | Most single-battery backup installs land around $13,500–$14,500, exact price up front. | For Tesla Powershare, Tesla publishes ~$1,950 hardware + $2,000–$4,000 install; if you have a Powerwall + Wall Connector already, no extra equipment. |
| Watch out for | Fuel supply during regional emergencies; noise ordinances; skipped maintenance. | Sizing games — you rarely need the whole panel backed up. We size to your real outages. | Only specific vehicles work today — Cybertruck, GM Ultium EVs, Kia EV9. No cross-brand systems exist. |
| At GreenKey | Coming — join the list | Installing now | Installing now |
Runtimes assume essentials — fridge, internet, lights, well pump, one HVAC zone — not every load in the house. Costs shown only where we or the manufacturer publish real figures.
A few hours, a few times a year — the classic Central Virginia storm profile. A battery covers it silently and instantly, and where your utility offers the right rate plan, it pays you back on every normal day too.
Well pump, medical equipment, all-electric home, week-long ice storm memories — endurance matters. That's the generator's case. An EV with V2H can also carry days of essentials, with the unique trick that you can drive it somewhere with power and refill.
Cybertruck, GM Ultium EV, or Kia EV9 in the driveway? You already paid for the biggest battery in this comparison. Check the compatibility table before buying anything else — it may change your whole plan.
Wrong question — best for what outages? Short and frequent: battery. Long and rare: generator. Big EV in the driveway: V2H changes your math entirely. Many homes end up with a layered answer, and the order you buy them in matters. That's the conversation we'd rather have than a pitch.
No, and be suspicious of anyone who implies it will. One 13.5 kWh battery runs essentials for 12–24 hours. It stacks, and it's the right tool for most Central Virginia outages — but the week-long storm is generator (or EV) territory, and we'll tell you which storm you're actually buying protection against.
In a properly designed system a generator can carry the house, and slow-charging a vehicle from house circuits may be possible depending on sizing — but there is no standard today for a generator feeding a V2H system as an integrated backup stack. Nobody should sell you that combination yet, including us.
Yes — home batteries are rated for outdoor installation and manage their own temperature. Winter matters more for sizing: heat pumps and resistance heat are big loads, so an all-electric home's winter backup plan needs more capacity (or a generator) compared to summer.
Two of three, today: batteries and V2H. Generators are next on the roadmap — the list is open, and the electrical groundwork (transfer equipment, panel capacity) is work we already do on any visit. If the honest answer for your home is "wait for the generator," you'll hear it from us.
Last year's outage history, your loads, your vehicles, your budget — we'll tell you which of the three fits, in what order, and what it really costs. You'll hear from us right away — and a real person, usually Jonathan, follows up within one business day.