Using an electric vehicle as home backup power in New York

Three kinds of bidirectional power

• Vehicle-to-load (V2L): outlets on the car, or an adapter, power individual appliances through extension cords, such as a refrigerator, a sump pump or a router. A cord must never be connected from the car to a dryer or range outlet to feed the house. This is illegal, endangers utility workers and violates NEC Article 702.
• Vehicle-to-home (V2H): the car powers selected circuits or the whole house during an outage, while a transfer switch, gateway or home hub disconnects the house from the grid.
• Vehicle-to-grid (V2G): the car exports power to the grid while connected to it. This requires utility interconnection approval and a compensation tariff, and it remains at the pilot stage in New York.

Hardware required by each brand

V2H is a system, not a single charger. Each manufacturer requires its own bidirectional charger and an isolation device, and some systems add a small battery that restarts the equipment after an outage begins. A GM vehicle cannot use a Tesla gateway, and a Tesla cannot use GM equipment.

Hardware prices change often, and installation cost depends on the panel, the distance to the parking space and the backup configuration. We price each system after a site review.

How New York treats a V2H installation

In New York City, a V2H system is electrical work that requires a DOB electrical permit and inspection under the 2025 NYC Electrical Code. On Long Island, the town, the village or an approved inspection agency handles the electrical inspection. Any device installed at the meter, such as a meter collar, and any service upgrade also require coordination with Con Edison or PSEG Long Island.

Systems that operate in parallel with the grid fall under the New York State Standardized Interconnection Requirements (SIR), which cover distributed generation and energy storage of 5 MW or less. The current version took effect on October 1, 2026. In a Public Service Commission working group, utilities have taken the position that bidirectional chargers need UL 1741 SB and IEEE 1547-2018 certification to proceed through the SIR, and other stakeholders have argued that break-before-make systems, which disconnect from the grid before discharging, operate as ordinary one-way charging while grid-connected. These are positions under discussion, not adopted rules, so we confirm the requirements with the utility for each project.

Compensation for exporting EV power to the grid (V2G) is not available to residential customers of Con Edison or PSEG Long Island today, to our knowledge.

How long an EV can power a house

Backup time depends on usable energy and on household consumption. Usable energy equals the battery capacity multiplied by the share you allow the car to discharge, less conversion losses. For example, a 100 kWh battery discharged from 90 percent to a 20 percent reserve, with about 12 percent conversion loss, provides roughly 62 kWh.

• Essential circuits in a New York City row house (refrigerator, lights, internet, boiler controls, sump pump), at roughly 8 to 12 kWh per day: about 5 to 7 days.
• A typical Long Island single-family day of 25 to 30 kWh: about 2 days. Tesla describes a similar result for Model 3 and Model Y, over two days for a home using 30 kWh per day, starting from a 90 percent charge.
• A house heated by a heat pump during a January outage can use several times its mild-weather consumption, so the same battery may last less than a day. Your own winter usage data from Con Edison or PSEG Long Island gives the most reliable estimate.

Power output is the second limit. Most V2H systems deliver about 10 to 11.5 kW continuously, which a central air conditioner, a well pump, a heat pump and an electric range running together can exceed. A backup subpanel or automatic load shedding keeps demand within that limit. The car also has to stay home and plugged in, so set a reserve that leaves enough range to drive away if necessary.

Manufacturer figures depend on their assumptions. At launch, GM described up to 21 days of backup from a 200 kWh Silverado EV, based on low daily consumption. These examples illustrate the method and are not a forecast for a specific home.

Battery wear and warranty

Backup use adds a few deep cycles per year, which is small compared with normal driving. Frequent daily discharge for grid services would be a different situation.

Review the vehicle warranty before installing any bidirectional equipment. Some manufacturers support bidirectional use only with approved hardware, and third-party equipment may affect coverage. The car also enforces its own minimum charge level during discharge.

V2H compared with a stationary home battery

The federal Residential Clean Energy Credit (Section 25D), which covered 30 percent of a home battery of 3 kWh or more, ended for expenditures after December 31, 2025. The IRS treats an expenditure as made when installation is complete, so a system paid for in 2025 but finished in 2026 does not qualify. Without that credit, the cost gap between a stationary battery and V2H has narrowed.

We are contractors, not tax advisors. For questions about credits carried forward from earlier years, consult a CPA such as Copper River Tax (copperrivertax.com).

• A stationary battery such as a Powerwall 3 (13.5 kWh) is always at home, can shift daily use to off-peak hours and can be approved for solar-plus-storage interconnection.
• V2H provides far more stored energy per dollar, because the large battery is already in the car, but only while the car is parked and connected.
• For Tesla Model 3 and Model Y, V2H requires a Powerwall 3, so the choice is both systems together rather than one or the other.
• In New York City, indoor battery systems are also subject to FDNY and Fire Code requirements on location and permits, which we review during design.

Preparing for solar and future bidirectional charging

• Size the charger conduit and wiring for a future 80-amp bidirectional unit, or install an empty conduit with a pull string.
• Reserve panel spaces or plan a backup-loads subpanel now.
• Account for the 120 percent rule for solar connections (NEC 705.12). A panel with a 200-amp busbar and a 200-amp main breaker allows a solar breaker of up to 40 amps; larger systems need a main-breaker change or a supply-side connection.
• Choose a location near the meter for the gateway, transfer switch or backup interface.

Our guides on solar for homes and on Tesla Powershare home backup cover those systems in more detail.

Planning a V2H installation

• Confirm that your exact vehicle, trim and build date are enabled for V2H in New York.
• List the circuits you need during an outage, such as heating controls, refrigeration, a sump pump, medical equipment and internet.
• Download 12 months of usage data from your utility account, including the winter months.
• Decide on a reserve level that keeps enough driving range.
• Review the warranty terms for bidirectional use.

We design and install bidirectional EV backup systems across New York City and Long Island, including Tesla Powershare, GM Energy V2H, Ford and Wallbox Quasar systems, with the electrical work performed by our licensed partner electricians. With your vehicle model, a photo of your panel and a list of what must stay powered during an outage, we can prepare a design and an estimate.