Why the sudden charge towards Formula E racing?

Electric car racing, otherwise known as Formula E, is now a growing sport after years of false dawns and false hope. Over the last couple of years it has grown much quicker than many people had expected and new teams seem to be joining on a regular basis. We are starting to see teams joining the Formula E set up which have either had no interest in or left Formula One some time ago. So, why the sudden charge towards Formula E racing?

Full article:-

https://www.linkedin.com/pulse/why-sudden-charge-towards-formula-e-racing-mark-benson

Great article - Formula E is the perfect test ground for EV technology.

I am still not sure about Formula E - what about the noise associated with an F1 car, surely that is a big attraction?