The Championship outfit secured the services of the 19-year-old from Old Trafford on a season-long loan.
"He's a huge talent, an exciting young English player and he's certainly one of those to keep an eye on," Coyle told BBC Radio Manchester. "As much as I'm a manager, first and foremost we're coaches.
"You want to help young players develop. If you can pass on any knowledge and experience to help young players go an have a glittering career, it certainly gives you a good feeling, because maybe you've played a little part in their development."
Powell had featured six times for United since moving to the club last summer.