This isn't a new idea. In fact some even talked about reverse concept where the EVs & Hybrids with solar panels could send excess power into the house for use. Unless someone works at night your electric car is going to be parked at your place of work usually not plugged into any power source let alone solar based power. Now if a place of business wants to erect aluminum/steel car port structures and run solar panels across the top of them leading to EV chargers in the parking lot or convert the top floor of a parking garage into a solar power plant. Well there are some options but this isn't as viable as it sounds. Especially Nissan's comments about Tesla's power plant. As people in the comments noted that battery's response time is one of its top features and has saved that region a fortune in doing so.