"for each basic Energy card".
Double Colorless isn't a basic Energy card. It's a Special Energy card. Won't work.
Okay, the rating. Generally, it's a poor card. Its only offensive attack is incredibly reliant on coin flips, which is never a good thing. Its HP will only cause it to be OHKO'd by Infernape, yet again. Waste of a card, to be honest, 5/10.
If I'm being brutally honest, Grass-types and anything with a Fire weakness will never work until there is something that can seriously counter that damn Infernape.