What's gotten popular out here for pole barn and remote buildings is the prop wind turbines. Looks like all aluminum on about a 30' pole, farmers exspecially seem to use them on buildings that just arn't convenient or cost effective to run electric to.
My place I have a old Aeromotor wind turbine that I rebuilt a few years ago to keep a remote stock tank full. My kid and I have played around with a few delcotron alternators to see what it will spin. With about 10+ mph wind I can easily spin a 90+ amp alternator.
Since I'm not their all the time I just don't want do deal with more battery's in my life.
Maybe in retirement. Have fun with your project.