First post here, so I apologize if this is the wrong area.I'm doing research and planning out a custom RV (cargo van/step van/box truck conversion...undecided), and looking to be as green and self sufficient as possible. Moving to a full time RV/Boondocking lifestyle.I've done a lot of research into solar, and believe I have a solid plan. From what I understand, it's always better to plan for more than what you think you'll use when it comes to power/water. So I wanted to look into supplementing a semi-standard "rooftop solar setup." Portable solar panels are an easy option, and a diesel generator is almost a must (from what I understand).I wanted to ask if anyone has experience with a portable wind turbine as a supplement to solar. I totally understand that, similar to solar, it's dependant on the available wind in the area....I also had a kinda crazy idea, that I wanted to share, and see if it's valid.Doing some research on turbines. Their running speed is generally between 12 and 30 mph, with a rated speed of 100 - 120 mpg (usually shutting off around 50 - 60 mpg).I wanted to see if you could add an inline speed reducer gearbox, between the blades of the turbine, and the generator itself. So that its running speed can be increased to between 50 - 70 mph. Thus enabling you to mount a horizontal shaft turbine through the roof, to generate power while driving at freeway speeds.There are quite a few horizontal shaft rotors that are fairly low profile, and be great for this kind of application. I'm just not certain it would work as I'm intending.(I understand a lot of concepts well, but don't have the practical knowledge. Some DIY House Repair as well as metal/wood fabrication experience.)

Welcome to the forum. It does sound like an interesting idea. But...I'm not an expert on the subject but, I think if this was a practical application RV's/electric vehicles would have the system installed.Possibly the small amount of electricity generated would be displaced by the extra fuel used from the drag of the system while driving?And it seems like a fairly complicated system with the addition of a gear reduction system.

ToastHater wrote:I wanted to ask if anyone has experience with a portable wind turbine as a supplement to solar. I totally understand that, similar to solar, it's dependant on the available wind in the area.Look to the sailing crowd ! My analysis is, that it is not worth the effort/money.It is difficult to get the sustained air flow for it to be practical.

While moving most high powered items are not used so guess you’re trying to charge your batteries. Spend the $$ on adding a second alternator to the engine or easiest way, diesel for your generator.

I would second having a second alternator to charge the battery bank while driving. I would guess in most situations, you are not charging them from fully dead, but rather just topping off since you have solar and the generator to help when you are set up. Way less involved and complex.

Go with conventional, tried and true equipment. You will spend a pile of money on an idea that is just an idea.

Portable Wind Turbine as a power supplement? | Good Sam Community

DrewE
Explorer II
Sep 18, 2020
Using the engine alternator to charge the batteries on the road will definitely be more efficient overall than a wind turbine. The power for the wind turbine comes from the vehicle engine, but you have all the losses of going through the drivetrain combined with the extra parasitic drag of the turbine (something it's most likely not especially designed to minimize, since in most cases it doesn't matter that the wind is impeded more than necessary). Directly connecting your generator (i.e. alternator) to the engine is more efficient.

An extra foot or so of height can make a significant difference on overhead clearances in some areas of the country, such as New England. In other areas, low clearances are far less common, perhaps excepting tree branches. If the extra height puts you above the basic legal maximum of 13'6", you'll need special permits for every trip and be very much constrained on where you can fit.

Working to minimize power usage is just as valid as working to maximize power production.
KD4UPL
Explorer
Sep 18, 2020
If you add the drag of a wind turbine to your RV then the engine needs to work harder to overcome the drag. You will be wasting energy with the "mobile while driving" set up. That's just a physics problem.

As for stationary use, small wind turbines are typically rated for maximum output at 28 mph wind speed. I don't know about you but camping with a steady 28 mph wind does not sound like fun at all to me.
The energy available in the wind is based on the cube of the wind speed so if you cut the wind speed in half you cut the potential energy by a factor of eight. So, let's reduce that wind speed to a more reasonable 14 mph. A typical small wind turbine like the Air-X is rated at 400 watts at 28 mph. With a 14 mph wind speed it is now only making 50 watts. No, you can't use a gear box to speed it up, again, physics is against you. There just isn't enough energy in slow wind to make it worth trying to recover it.
profdant139
Explorer II
Sep 18, 2020
It was a fun idea, though. Keep thinking outside the box!!
BarneyS
Explorer III
Sep 18, 2020
Moved to Tech Issues forum from DIY.
free_radical
Explorer
Sep 19, 2020
ToastHater wrote:
First post here, so I apologize if this is the wrong area.

I'm doing research and planning out a custom RV (cargo van/step van/box truck conversion...undecided), and looking to be as green and self sufficient as possible. Moving to a full time RV/Boondocking lifestyle.

I've done a lot of research into solar, and believe I have a solid plan. From what I understand, it's always better to plan for more than what you think you'll use when it comes to power/water. So I wanted to look into supplementing a semi-standard "rooftop solar setup." Portable solar panels are an easy option, and a diesel generator is almost a must (from what I understand).

I wanted to ask if anyone has experience with a portable wind turbine as a supplement to solar. I totally understand that, similar to solar, it's dependant on the available wind in the area.

...
I also had a kinda crazy idea, that I wanted to share, and see if it's valid.

Doing some research on turbines. Their running speed is generally between 12 and 30 mph, with a rated speed of 100 - 120 mpg (usually shutting off around 50 - 60 mpg).

I wanted to see if you could add an inline speed reducer gearbox, between the blades of the turbine, and the generator itself. So that its running speed can be increased to between 50 - 70 mph. Thus enabling you to mount a horizontal shaft turbine through the roof, to generate power while driving at freeway speeds.

There are quite a few horizontal shaft rotors that are fairly low profile, and be great for this kind of application. I'm just not certain it would work as I'm intending.

(I understand a lot of concepts well, but don't have the practical knowledge. Some DIY House Repair as well as metal/wood fabrication experience.)

Take a look at these vertical chargers
Specs beat any horizontal windcharger of same size

https://www.windside.com/

Instead of roof how about mounting it on a back bumper and make it expandable above roof when parked.
Or on front bumper and it would catch plenty air when driving
Features include:

2-5 m/s cut-in wind speed
Up to 60 m/s max wind speed
50+ year lifespan
5-yr maintenance-free (optional)
Soundless Operation
No vibration
Graceful rotation

Primary function is to charge 12/24/48VDC battery banks which power DC loads including DC/AC inverters for 110/230VAC output.
free_radical
Explorer
Sep 19, 2020
jkwilson wrote:
Running a wind turbine while towing will cost you more energy from your truck than it will produce. It will be at best the same as running a generator. Simple laws of physics.

I guess OP has something like this in mind

https://en.wikipedia.org/wiki/Ram_air_turbine

Not very practical to put on RV imo
Bert_the_Welder
Explorer II
Sep 20, 2020
Another potential issue would be the strain on the mounting system/fasteners on the roof.
jkwilson
Explorer II
Sep 20, 2020
free radical wrote:
jkwilson wrote:
Running a wind turbine while towing will cost you more energy from your truck than it will produce. It will be at best the same as running a generator. Simple laws of physics.

I guess OP has something like this in mind

https://en.wikipedia.org/wiki/Ram_air_turbine

Not very practical to put on RV imo

I actually worked on two systems mentioned in that article, though on one I only worked on a shipboard version so no RAT.

Even a RAT consumes more power from the vehicle than it produces.
ToastHater
Explorer
Sep 20, 2020
Thank you all for the advice and information. It was kind of a wild idea, and I had no idea about the energy potential of the alternator (or dual alternators).

Yeah. I used the wrong terminology in the OP. This is what I had in mind. Posted up on the roof.
Dtank
Explorer
Sep 23, 2020
profdant139 wrote:
It was a fun idea, though. Keep thinking outside the box!!

.......and another fun idea.......

maybe change your ID to "Rube Goldberg, Jr." ??

:B
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