Yes, POTENTIAL is a Scrabble word!

Letter values in Scrabble US: P 3, O 1, T 1, E 1, N 1, T 1, I 1, A 1, L 1.

Is it a valid word?

POTENTIAL is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

the inherent capacity for coming into being
the difference in electrical charge between two points in a circuit expressed in volts

Also: electric potential, potential difference, potential drop.