As power outages become more common (impacted 25% of US Homes in 2023) across the US, lots of attention is channeled towards traditional gas-powered home generators and residential battery systems (i.e. Tesla Powerwall), as back-up power solutions.
Another emerging solution, that gets less attention (for now, likely to change) is relying on the batteries of EVs to provide electricity during power outages for "select appliances / lights" in a household. A capability known as Vehicle-To-Load Technology (V2L).
While Vehicle-To-Load Technology (V2L) is a relatively new technology, included on around 15 different EV models, as of the beginning of 2025, expect that it will grow into a standard feature for electric vehicles, over the next two to three years. It costs little for manufactures to include and adds lots of value, especially in areas prone to power outages.
How Vehicle-To-Load (V2L) Technology Works, And What Do Transfer Switches Do
With Vehicle-To-Load Technology (V2L), it's possible to run extension cords to keep the power on an essential appliance, such as a refrigerator, air conditioner. oven, etc. However, running long and multiple extension cords is pretty inconvenient and doesn't solve the problem of needing to keep a bunch of essential electrical circuits powered on during power outages. This is where transfer switches add value.
Instead of running extension cords from an EV through a house, transfer switches (which cost just a few hundred bucks) are used to direct power to a few select circuits within a fuse box. By routing these circuits to the transfer switch, EVs can then be connected to the transfer switch and provide power for select essential functions, up to a certain "load limit".
A limit that, as of now, typically peaks at around 10 kW, enough power to keep HVAC systems, refrigerators / freezers, lights on.
Vehicle-To-Load Further Supports The Value Proposition of EVs
Since EVs have much larger battery packs than home battery energy storage systems, the inclusion of Vehicle-To-Load Technology (V2L) technology helps to support the value proposition of EVs. As an example, it costs upwards of $15,000 to install a Tesla Powerwall 3, which can store 13.5 kWh of energy, while EV's now commonly feature 75+ kWh of energy.
Cost Advantages of V2L and Transfer Switches vs Residential Battery Back Systems
As EVs ship with larger battery packs, it's a lot more cost efficient to rely on EVs with Vehicle-To-Load Technology (V2L) and transfer switches during power outages, than residential battery energy storage systems. Homeowners will be more comfortable adding on a transfer switch costing a few hundred dollars to their fuse box, than they will be adding on a back-up battery that costs $15,000+ (as of now).