When we drive interstate or internationally, we expect fuel everywhere to be fairly similar. Now, to ensure that same security is there for drivers of plug-in hybrid vehicles, a number of major carmakers and energy companies have come to an agreement on what the plug should look like for the new cars.

In the end, the companies agreed on a three-pronged, 400-volt plug which was presented at Monday's Hanover Technology Fair. The reasoning behind the decision to make the plugs uniform between different companies is that a car must be able to be recharged in one country in exactly the same way as in another.

The major carmakers on board with the agreement include Volkswagen, BMW, Ford, General Motors, Fiat, Toyota and Mitsubishi, which together account for the large majority of global vehicle production. The agreement also includes major European energy firms, such as the German-based companies E.O.N and RWE, Swedan's Vattenfall, France's EDF, Spain's Endesa and Italy's Enel.

The announcement represents a significant move forward for electric vehicles, and the mass embrace of the battery instead of oil is beginning to force companies to concentrate on building suitable infrastructure for such a switch.

No timeline for the new common plug has been given, but the fact that the plug is capable of handling 400-volts and most homes are only 240-volt seems to suggest that the energy companies involved may be considering high-powered recharging stations as an option for electric car motorists.