He did not require sustenance, but occasionally ingested semi-organic nutrient suspension in a silicon-based liquid medium to lubricate his biofunctions. (TNG: “Deja Q”) Though capable of consuming more traditional food and drink, Data had no sense of taste and therefore tended not to bother eating. (TNG: “Hero Worship”)
So, you could probably derive some of the organic components from bananas, but generally no. He’s not really banana-powered.
I was just about to post this! Now I really want to know if Data’s neural network was banana powered.
“If one crunches the numbers (as they do in the original article), it turns out that bananas pop out a positron every 75 minutes or so.”
From the Memory Alpha wiki:
So, you could probably derive some of the organic components from bananas, but generally no. He’s not really banana-powered.