With power outages across the country leaving people without heat in the middle of ice storms, this may seem like a good time to reevaluate the wisdom of switching to electric cars.

After all, not being able to recharge your batteries would leave you not only cold, but also without the means to drive to a shelter. A trusty internal combustion engine in the garage could be a life saver.

On the other hand, people stranded without power–and blocked by snowdrifts or icy roads–might just wish they had a few kilowatt hours of power sitting in their garage instead. AC Propulsion is a small California-based company that’s converting Scion xBs into lithium-ion-powered electric cars. And all their systems can be plugged into the house–not just to charge, but also to deliver electricity back to the grid. With such a system, as well as a switch to disconnect the house from the grid, it would be possible to run lights and even electric heaters off energy in the car. That’s assuming the owner had the forethought to keep the batteries topped off as the storm approached.

Plug-in hybrids would be even better. They could also be made to deliver power back to the house, or even be made to just plug into a portable heater. And they’ve got a gas engine on board that will recharge the batteries–or allow an escape if the roads are clear.