Small wind turbine

[Forbisher]

5 days of clouds=squat from pv. A wind turbine could save your ass if you're off grid. It will be thousands cheaper than 5 days worth of batteries. No math necessary.

Yeah, but if you have no wind or low wind like most of us even when its cloudy then a wind turbine is making squat too so thousands spent for no reason.

Nobody here is saying dont use a turbine if you are in a windy area but the reality is that most are not.
Do you have a decent amount of wind at your location?

 

[snoobler]

I apologize snoobler, i did not mean a slam at Will at all. All i meant is i did not know anyone with more info than this guy that i had heard about. He definitely is not scientific at all but fun to watch and has had some decent luck with turbines.

LOL... sorry. That came out way too strong.

I live in the desert southwest. Spring can be crazy windy, and monsoon season in the fall generally produces cloudy, windy days.

So do I. Mesa and ENE of Show Low. How was your monsoon this year?

5 days of clouds=squat from pv. A wind turbine could save your ass if you're off grid. It will be thousands cheaper than 5 days worth of batteries. No math necessary.

Actually, that's not necessarily true. I've been surprised at how much my 3kW array can produce in overcast conditions. It's not much, but it's more than a wind turbine in typical conditions, and I have another 3kW of panels on hand to deploy. In all honesty, if I took my $2400 and bought another 4.8kW of solar, that would likely benefit me more than wind, BUT I want the OPTION.

Also, when you're off-grid, you're tailoring your lifestyle to available resources. If it looks like you're going to be in for poor solar conditions, you're dialing back and/or using your generator - which was about 1/5th the cost of a wind turbine.

As I stated, I'm pro-wind, but it's the wrong choice for the vast majority of the country.

 

[Forbisher]

I live in the desert southwest. Spring can be crazy windy, and monsoon season in the fall generally produces cloudy, windy days.

Crazy windy is not good for wind production or maintainance of your turbine which should be on a expensive 50 foot or taller tower. Have fun up there fixing it.
Also be prepared to spend a lot on a quality turbine if you want it to not self destruct.
Solar is pretty much maintenance free.
Also wind power is not easy to control like solar with dump loads and other complications.

I can count the windy days in my area on my fingers plus the wind is too gusty and strong for a turbine which would probably have to be shut down to protect it. Otherwise a few mph occasionally.

 

[snoobler]

Ok, it doesn't make sense for you. That doesn't mean it doesn't make sense for others. Different perspectives and situations are the reasons for the forum existing, are they not?

Go find someone with a wind turbine in your planned area. Ask them how much it produces, and ask them if they would make the same choice.

The wind supply guy I'm working with is actually pseudo-anti-wind. One of the first things out of his mouth was, "you need to keep your perspective on wind. In this area, you're going to average about 80-100W over the year." He also said you get WAY more bang for your buck with solar.

Wind also tends to die WAY down overnight. It can be 20+mph for most of the day, but as the sun goes down, it drops below 10 mph.

 

[tazmann]

5 days of clouds=squat from pv. A wind turbine could save your ass if you're off grid. It will be thousands cheaper than 5 days worth of batteries. No math necessary.

I think a genset in that situation would be the best option

 

[gnubie]

Keep it civil people.

 

[Forbisher]

So, your arguements against wind power are (1) there's not enough wind, and (2) there's too much wind.

Yes there is definitely such a thing as too much wind and the wrong kind.
You need smooth laminar flow for good power production.
Strong gusts and from various directions will destroy turbines and result in poor production due to the turbine furling to protect itself from overspeed.

 

[gnubie]

The mop has been deployed in this thread. Keep on topic. Discuss small wind turbines. Attempts to derail the thread by introducing multi-million dollar commercial installations is not discussing small wind turbines.

 

[tazmann]

Success Took it down this morning and pulled it apart, every thing looked good so I just cleaned up the ring with armature stone. There are no circuit boards inside, pretty simple setup. I remember one of Johns videos where he was talking about the ac voltage being around 60 volts on 12 volt systems and the best I got was 65 volts at about 2800 rpm so I thought maybe it will work better on 12 volt system in light air. The Seller claims it is for 24 volt systems only and the charge controller states 12/24 volts just hook battery up first so I tried it and Wala no pretty blue smoke and it worked, kicks in and starts charging at about 4 MPH wind, just a couple watts but that is better then watching spinning like crazy at 5-1/2 MPH fluttering and making a squealing noise producing 0. Yesterday we had a little better winds, gust to 10 MPH but I still didn't get much 1AH. Today wind are ranging 3-6 MPH which is the norm so we shall see what I get for the day

 

[Hedges]

5 days of clouds=squat from pv. A wind turbine could save your ass if you're off grid. It will be thousands cheaper than 5 days worth of batteries. No math necessary.

Looking back at my post, "Do the math" was what I said regarding trackers vs. extra panels on fixed mount.
I did not apply it to wind vs. PV.

Trackers vs. more panels on cloudy days? I'll bet more panels wins. None are getting good direct light, but more panels = more area capturing diffuse light from clouds.

 

[svetz]

... Yesterday we had a little better winds, gust to 10 MPH but I still didn't get much 1AH. Today wind are ranging 3-6 MPH which is the norm so we shall see what I get for the day... So, the converse of the low-wind equals low-energy issue... Do you know what the upper wind speed is and are you ready for it? The power output is a cube of the wind speed, so even if you're just messing about with it at this point you probably need some plan should a microburst roll through. As you can see in the generic graph to the right, at some point too much wind becomes a huge danger. Sadly I don't know much beyond that it's not something that you can just switch off and not have to worry about it melting down.

 

[Hedges]

So, the converse of the low-wind equals low-energy issue... Do you know what the upper wind speed is and are you ready for it? The power output is a cube of the wind speed, so even if you're just messing about with it at this point you probably need some plan should a microburst roll through. As you can see in the generic graph to the right, at some point too much wind becomes a huge danger. Sadly I don't know much beyond that it's not something that you can just switch off and not have to worry about it melting down.

Mechanical shutdown is one method. Adjustable blades can furl. Turbine can turn sideways to the wind. On smaller turbines, this is sometimes an offset of the generator from pivot, held by spring. Above some wind speed (force), turbine rotates 90 degrees. Windcharger did that. Others break upward. Some have mechanical brakes (which of course have limits - I've seen pictures of turbines burning.)

 

[tazmann]

Well on rare occasions winds have hit 80-90 MPH, Am I ready nope, I can get it down quick but I have to be home for it. The charge controller has built in braking that comes on when it hits top charge voltage, as far as I know it shorts the 3 ac legs together. I have no idea if that will work in high winds or not.
Today turned out to be a sucky day for winds, keeps dying. I guess I should get out the mig or paint gun wind always shows up trying to do ether of them

 

[tazmann]

Did a little experimenting with mounting the turbine. Have it at 15' used 12' of 1-1/2" pipe pinned at bottom so it pivots up and attaches to motor home and so far I am happy with it, was worried about the noise but I dont even hear it inside. When I am done prototyping I will redo it in aluminum pipe. No climbing latter's or walking around on roof just pull rope from ground. Anyway what I am thinking now is it would be nice to charge the 24 volt system when the winds are up so why could I not just install another charge controller and toggle the ac side to one or the other ? the charge controllers are cheap

 

[snoobler]

That's impressive. They often cause resonance depending on the structure. Metal building and shipping containers are like amplifiers. The mounting scheme and the wood/insulation may help. How's the performance been?

Don't see why you couldn't have a transfer switch between charge controllers.

 

[tazmann]

How's the performance been?
Not good winds have been fickle to none existent, today is a little better 3 to 8 MPH, for a bit there is was cranking out .27 amps LOL

 

[tazmann]

I went ahead and ordered the switches, charge controller, and 3 wire waterproof connectors should be in today. Anyway Last night I was thinking it would be nice to be able to manually activate the brake mode Then I guess the hamster jumped back on the wheel and it dawned on me I don't need a second incoming switch for braking or a second charge controller to do what I want. Take the 3 pole double throw on-off-on, one side passes through, middle is off the other side gets jumper between the 3 poles, creates on-off-brake then on DC output side run DPDT on-off-on switch with one side going to 12 volt system the other to 24 volt system with the middle being off when system is not in use . Lot less complicated than the original plan

 

[Hedges]

Middle position off would make a voltage spike - can that damage insulation in windings?
Opening the "brake" position (or other position) interrupts current, causing an arc.

Consider designing a snubber (series R-C is one kind) to go across the switch and minimize arc.
Having "make before break" (or in this case, "before brake"?) avoids the spike. It also shorts out battery (bad) or input to charge controller (just dumps cap?) so want to prevent backflow with diode?
3-phase alternator has diodes, so put switch on AC side. But didn't you say "3 pole" switch for the AC side? No need to disconnect in that case, just crowbar the 3 legs with 3PST switch. Actually, DPDT is all it takes to short 3 wires or isolate them.
Snubber on AC side needs to minimize power loss. But with diodes and capacitor already in the charging circuit, that may be sufficient snubber.

 

[tazmann]

Middle position off would make a voltage spike - can that damage insulation in windings?
Opening the "brake" position (or other position) interrupts current, causing an arc.

Consider designing a snubber (series R-C is one kind) to go across the switch and minimize arc.
Having "make before break" (or in this case, "before brake"?) avoids the spike. It also shorts out battery (bad) or input to charge controller (just dumps cap?) so want to prevent backflow with diode?
3-phase alternator has diodes, so put switch on AC side. But didn't you say "3 pole" switch for the AC side? No need to disconnect in that case, just crowbar the 3 legs with 3PST switch. Actually, DPDT is all it takes to short 3 wires or isolate them.
Snubber on AC side needs to minimize power loss. But with diodes and capacitor already in the charging circuit, that may be sufficient snubber.

Good questions . I am just kinda going by what the charge controller does at a set high DC voltage it shorts the 3 phase legs together to stop output and I am assuming it disconnects from the DC side at the same time, that alone seems to me would be damaging but I guess it depends on the output at the time. As far as diodes I think they are in the charge controller there were none in the alternator. My plan is if i get into an over powered by wind situation is put a load on it slow it down and engage the brake then drop the turbine

 

[tazmann]

Success I think Winds are not in my favor, blows 6-7 MPH then dies. Anyway the switch I ordered I thought was on-off-on but it was on-on so it turned out better no off position for a potential spike . The brake works good and the only quirk is when switching from say 12 to 24 volt you have to pause about 10 seconds in the off position then switch to 24 volt if you don't the controller thinks it is still in 12 volt mode and engages brake. I will run it a week or two like it is to test it in hopefully better winds. I still have the option of two separate controllers. Looking at possibly putting a little bigger blades or changing the angle of attack of the ones on it for a little better torque at slow speeds, should help a little charging with 12 volt.