5 ms·You could have them power fans or keep the lights on. Things that can use just a few watts.by akvadrako 4y agoYou could have them power fans or keep the lights on. Things that can use just a few watts.agumonkey 4y agoeach one yes, but if you have 20 persons averaging 100W, you can power a kettle :)hinkley 4y agoHaving been to a gym, I sincerely hope any power scavenged is use to power the ventilation system.