Windmill atop RV

A wind turbine is not something I've ever seen on a vehicle, and likely never will. It would take considerable strength to hold that up against 70mph winds, and likely be very noisy. The ones I've seen at campsites are. Otoh, solar charges 12/7 with no noise or danger.

Your alternator may charge the house batteries while driving.. depends. Your generator definitely will.

Batteries in a MH are charged while driving.

I have seen a few RV with wind generators. They are mounted on a pole at rear of RV. But only used when parked.

Other then noise issues, and loss of mpg due to increased drag, you have the 13'6" height limit to deal with.

Alternator should charge your batteries while driving.

A wind turbine mounted on a vehicle will not get that much electricity while driving, but will have to be mounted extremely well, or it will shear off, especially at 65-70mph. While driving, if one needs to charge things, I'd see if another alternator can be placed which could be used for this purpose.

When parked, usually one has to set up some type of extension or tower for the windmill. Surface winds tend to be low and flaky, so one needs to get the turbine well off the ground to be of any use.

Another issue is that windmills can work in some areas (deserts, places near lakes), but would be spotty at best in others.

I'd first go with a solar charging system, either roof mounted or on a portable array. Then, see about putting a mount point on the RV for a wind turbine.

Some aircraft had drop down hydrualic wind driven RATs (rotating air turbines) that were used in emergencies. Seems to me that a TT with a few extra batteries could store enough juice with a wind driven generator to dry camp for a few days and with enough to get to house voltage it would an alternative to a noisy generator.

Mlts22, I was just thinking not planning on doing anything. You know how we ladies do...I was wondering about effect on MPG but couldn't visualize that they would have that much effect. My thought was the three thin blade ones that are use to produce large power grids. So if not on top how about in front? How about a wind tunnel design, wind goes in turns fan and exits. Rbtglove has a great idea to. This was just an idea to generate;0) some ideas, not trying to develop the greatest money maker since the computer...then again...hmmmmmmmmmm.

It would cost substantially more in terms of lost MPG (big increase in aerodynamic drag) than it would produce.

Said another way, the alternator would be a much more efficient way to produce power.

Alternator will be the primary source to charging the house batteries.
Generator can certainly be used to suppliment the alternator or reduce the load on the alternator.
If adding hardware to the roof I recommend solar panels. And yes solar charges just fine while in motion... as long as you have sun.
I would pass on the windmill unless you have a permanent site with a reliable breeze.

Small wind HAWT generation requires relatively large blades to get significant power in a stationary installation. Even if you could change the props to a "road worthy" size, the vibrations and excessive continual wind speed would chew everything up in short order.

You could try to build a tunnel through your vehicle and install an axial fan to harvest some power. Get back to us on that.

I would be very wary of attaching a mast and some of the small wind generators on my RV. There is a lot of vibration in some instances.

FWIW, I have a HAWT that produces DC. I get the benefit of the generator's bearings along with the shaft, coupling, and pillow blocks that comprise the prop shaft support. I have a 7'D aluminum propset. There is virtually no noise from the system at a height of 15'.