Honda will use Accord Plug-in for vehicle-to-grid demonstration project.

Honda is joining a pre-existing vehicle-to-grid (V2G) demonstration project involving the University of Delaware and NRG Energy. Honda will use one of its Accord Plug-in Hybrid models as a back-up grid-power source when conventional power supply drops and demand surges. NRG Energy started funding its testing system with the university earlier this year.

In order to participate, Honda is installing a bi-directional on-board charger in the Accord PHEV. The test is part of a broader effort by automakers and other entities to explore how plug-in vehicles can help regulate the grid something that will become more common as renewable energy sources become more common.

Nissan has been running similar demonstration with its all-electric Leaf. Recently, Nissan tested its "Vehicle-To-Building" system in Japan, which involved a half-dozen Leaf vehicles powering an office building during peak demand, then having the cars re-juiced when electricity costs go down. In 2011, Nissan also started getting results from its "Leaf-to-Home" system, which uses the EV to power a house during blackouts.