Using a two-way charging system, fleet operators in Denmark were able to achieve a $1,530 annual profit.

Nissan is apparently experimenting with two-way charging systems that could allow EV owners to make money by supplying power back into the grid during peak demand times.

A trial involving Nissan and Italian utility company Enel SpA is said to involve more than 100 cars throughout Europe. In Denmark -- currently the only market where the pilot program makes money from the scheme -- vehicles achieve an annual profit of around $1,530 USD, according to Bloomberg.

The system requires a two-way charging system that fills an EV's battery during low-demand hours, when electricity prices are low, then pushes it back into the grid when the value is highest. Such a configuration is apparently similar to individual solar and wind connections that supply power to the grid when generated electricity exceeds home demand.

Nissan Europe's director of energy services, Francisco Carranza, warned that the automaker and its partners need to be aware of creating new problems by 'blindingly' deploying massive numbers of cars without any control over the way the electricity is drawn from or put back into the grid.

The company is said to be eyeing the UK as its next potential market, though the fleet will need to include around 150 vehicles to be paid for power supplied by the project.

It is unclear if the company is considering similar initiatives in the US market.