Att: wind turbine and solar people

[travis E]

I have interest in putting a wind turbine on my new property. The down falls are: I dont know much about them and they sound real expensive.

I would like to sell power back to the power company but is the cost of a wind turbine ever going to pay for its self??



Travis

[rreidnauer]

There certainly is the possibility of it paying for itself if you take advantage of government programs, some of which will pay up to 70% of the installation costs. At this point I haven't researched it much myself, as every nickle I can store away right now will go into the log home I have plans for in the not-to-distant future. But put the old hound nose to the ground, and I'm sure you'll sniff out some positive information you are seeking.

[wood bug]

I was listening to a radio show a few weeks back talking with an installer basically he was saying that to run a "complete" home with every day ammineties it runs around $25,000 -$35,000 for an install of course he was stressing that it could be cheaper if you use only the basic "life support" things he included most appliances not to mention the maintenance ( battery) which is getting better with technology improvements, He also said you could get in for as little as about $5,000 for like a water heater and a couple of lights, as for me in lue of the prices I will put my money into my house until I move to a more remote location like Alaska.

[travis E]

Thanks guys for the info.

I think I will pass with those kind of prices.

I am going to look into a tankless water heater to save propane. Any experience with them?

[gregorama]

Some discussion here..
http://www.loghomebuilders.org/forums/viewtopic.php?t=789

[ChainsawGrandpa]

A few years back Up at EAA Arlington I taught a class on subsonic
aircraft design. I was always told that an airfoil driven by the wind
is much different from an airfoil that drives the wind. Hmmm...
some recent research apparently show they have a lot in common.

So far, this is what I have for a small eight bladed turbine driving
an aircompressor.

1. The compressor stroke is short...very short about 3/4"
2. I'll need some very large storage tanks for the compressed air.
3. The air must be released in a cascade system.
4. The airfoil is NACA 4424
5. The angle of attack is 9 degrees
6. Each blade is 120"
7. The root chord is 17"
8. Tip chord is about 12 1/2"

Best to run the Reynolds numbers. Sounds complicated but it's
actually very simple. The very best reference I have ever found
is RC Model Aircraft Design by Andy Lennon.
Hope this helps a little, but hey, these are my answers. Might be
best to do a little study before you start cutting foam and laying 'glas.

-Rick

[ChainsawGrandpa]

I was in a hurry to get the information posted before I timed out.
Should have also mentioned:

*Wash out is somewhere between 2 - 3 degrees
* NACA 4424 has a "semi" gentle stall break
* This will run in a gentle wind but about 4 mph or more is beneficial.
* The compressor is mounted on the turbine
* The compressor is Goodyear HTD or serpentine belt reduction drive.
* The compressor is about 3/4 - 1 cubic inch/stroke

Seems like a big fan to get a maximum of 1/2" per revolution, (just
how many cubic inches are in a big propane cylinder??) but this allows
for air to be compressed in a slight breeze. If you have higher velocities,
and consistent wind then the drive ratios can be changed. YMMV.
Remember, I need to have air...any air in my tank, and the compressor
will be driving a tank up to 200#. I also have very little wind where I
am situated. The good news is that modifications are easy. Change
the ratios, and if you have enough wind, add a second compressor.

A few miles away is a metal recycler. There are some propane tanks
that are about 4' x 24'. Now those at 200# would keep my sander
running for a few minutes!
-Rick

[ponyboy]

Hummm... I replied to this yesterday and it seems to have disappeared. :?:

Doh! :shock: The link I gave yesterday just lost their domain name. Here's one from the Popular Mechanics web site.

http://www.popularmechanics.com/science/technology_watch/1288371.html


Jeff

[ponyboy]

Here's another different type of windmill I just ran across.

http://www.windwandler.de/eng/index.html

[gabriel_h]

Ponyboy,
I've been looking into wind turbines also since I'm worried that solar power and a passive solar design won't be of much benefit on overcast winter days. In NC the average wind speed is 8mph at ground level, which is far too slow for most systems. I was excited when I saw the roof-mount on that site, but then I did the math... 8mph is only 4 m/sec which only yields 18 watts according to their charts. What can you do with 18 watts? Then I started looking into other roof mounted wind turbines and found out that sound and vibration are serious problems that have to be dealt with, so mounting more than one wind generator on your roof probably wouldn't be a good solution either. I don't know. It's hard to let go of the idea of a wind-turbine, so I might eventually end up building one myself and placing it on a tall pole-mount (80 feet+) but it won't be a high priority since I doubt I'll get much of a return on that investment. Even with that cool looking "Windwandler" design I don't think a roof-mount turbine would be practical for anyone unless they lived somewhere where it is very windy. (Ahem - Kansas...)

[ponyboy]

Gabe,

Yup, 8mph is not much to work with. I agree with not mounting it on the roof. Even if it was made for it. I liked the two windmills I had links to because they were different and not the same old standard windmill. :)

I think even somewhere sunny all the time it would be hard to relied on solar.(unless you had $$$ solar panels and $$$ batteries) :shock:

A buddy of mine had an idea to bury a very large air tank and have the windmill just pump it full of air so when you need the extra power you just bleed off the air through a turbine and generate power. This way you could store all the wind power from the summer time and use it in the winter when you need it. Not sure if it would be very doable, but I though it was interesting.

Jeff

[GrafikFeat]

Google works wonders...

http://www.planetarysystems.com/

As well as do a search on this board. There are a lotta links here now.

Jim

:idea: :idea: :idea: :idea: :idea: :idea: :idea: :idea: :idea:

[ChainsawGrandpa]

One more recent discovery. When using a large number of blades it
is good to use an uneven number to discourage harmonic surging. (?)
Dunno, doesn't make sense right now, just what I was advised. My scenario
was to use eight blades but was advised that seven (or nine) would be preferable.

Also, was told about a windmill using a 3/4 ton axel. It would
use magnets in the plunger rod which would be passed through
coils. It would create AC power (I think) but at varying frequencies.
The sole purpose would be to supply the electricity to a radiant
electric heater. Just to be used for space heating only.

-Rick

[Cheam]

This is a few years off yet but is somthing worth watching for if you live in a low wind area.

http://www.expressnews.ualberta.ca/article.cfm?id=6792