According to the Press Association, di Grassi spent last week at the Circuit de L'Eure, just outside Paris, testing for the nascent formula.
"Formula E is the future of racing," ex-Virgin Racing driver di Grassi said after testing the series prototype. "Both the top speed and acceleration of the cars were great and I believe this car will reach even higher performance levels in the years to come."
He went on: "The engine torque has impressed me a lot, and although the car isn't easy to drive, it will be a great challenge to race it on the streets.
"One of the most striking things when you drive the prototype is the noise. There is sound, lower than combustion cars and of a different nature - a futuristic sound. The aero noise can be heard very clearly at high speeds too. It is a completely new experience.
"I believe this will change the perception of people regarding electric cars. Formula E is the perfect merge between fast racing cars and green future technologies. This is a great opportunity for car manufacturers too."