Can my EV provide emergency power to my home?
Sometimes our homes lose power. Lately, this has occurred intentionally, as utility companies de-energize power lines to reduce the risk of fire during dry and windy conditions.
Therefore, many people want to know if the large battery in their EV can be used to provide power in their home.
In principal, EV batteries can provide power in emergency situations, as well as during other times. This concept is known as Vehicle-to-Home power. In addition to providing emergency power, this kind of bi-directional charging will allow homeowners and fleet managers to use the energy in their car batteries to power buildings when electrical rates are high, and recharge their vehicles when rates are low. This will not only save money, but will provide benefits to the electric grid, since high-rate times are also high-demand times, and reducing demand during these peaks is helpful both to the grid itself, and to the environment.
However, the technology is not yet fully developed.
Several car makers are working on it. Nissan, one of the largest EV makers, has developed the necessary technology, and is testing it in Japan and elsewhere. It is hoped that the modules required to create Vehicle-to-Home microgrids will be available in the US soon. Nissan is the first manufacturer to prepare their cars explicitly for two-way charging, ensuring there is no risk to your warranty if you deploy this technology when it becomes available. You can read more here, or on Nissan's website here.
Some third party manufacturers are also working on systems to accomplish this. One such company is Wallbox, that is already promoting their Quasar bi-directional charger here in the US.
In addition, some creative types have figured out how to work around the limitations, and extract juice from their EV during power cuts. They have even posted videos online describing their workarounds. However, these systems are not approved by the manufacturer, and we cannot recommend that you use them as they are untested, unproven, and possibly unsafe.
In short, EVs will power homes and businesses in the future, and will provide backup power in the case of power outages. Unfortunately, they do not do so quite yet.
For a thorough summary of the challenges in this area, we refer you to this article from Wired: “No, You Can’t Power Your House With Your Electric Car”