[tpkj]

No, it has not taken off exponentially yet in the way the Tony Seba video demonstrates with a picture of 5th Ave in NYC in the year 1900 where there are lots of horses used for transportation, and only one car, compared with a picture of the same street in 1913, where the street is full of cars, and there is only one horse to be found.

[jessaustin]

Scroll down the page I linked to the graph "Exponential Growth of Solar PV". A straight line on a log graph is exponential by definition.

[tpkj]

There's the formal definition of "exponential", and then there is "exponential" in the sense of completely disruptive and transformative as in the example Tony Seba gives. I am referring to the latter.