And the saga continues...
January 1, 2011 Due to the dual General turbines being a total failure for generation, I took them down permanently today. NOTE! NOT TRUE I PUT THEM UP AGAIN! Also, while I was dismantling them I noticed I could hear noise coming from the Whisper 500, which means the protection tape on the leading edge of the 10 month old props is coming loose. This will rob the turbine of rotation speed and reduce generation. It's not too bad yet, but experience is, it will get worse fast now. If this is true, I don't think I'll put it back up either.
1/1/2011 Took down Missouri Wind's Generals due to absolutely zero KWh generation even in high wind. I saw the two of them briefly generate a total 220 watts. Turbines sold as 1500 watt turbines that only generate 110 watts in 40 mph gusts is just wrong. Beware of these turbines for 48 volt applications. I've tried reworked, tried rewired, tried new parts, tried more and less fan blades, and remind you I have an anemometer on this tower, and nothing works to increase generation to the point I get any KWh at all. Just a brief few watts at the highest wind gust. NOTE! Look to the bottom of this page to see the latest findings on some success and what we think may be at the root of it.
1/4/11 I am starting to think 10 KW solar PV and a 6 KW backup generator, hopefully running on steam from wood waste, is a better investment than having any wind power at all, in Missouri. The Kestrel 3000 watt/hi voltage turbine with support hardware is about $13,000, not including a tower which I already have for the Whisper 500, if I simply replace that turbine. Even if the Kestrel generates twice the power of the Whisper, or 200 KWh/month in winter, I could run the 6 KW backup generator full time on gasoline for a long time for 13 grand, or 26 grand including a new tower. 200 KWh / 6 KW = 33 hours. A 10 HP B&S will use 1/2 gallon per hour. 17 gallons of fuel = $51.00. Steam power would be $5.00 for gasoline and oil to cut the wood and oil the steam engine.
If we use a 10 HP B&S 4 months of the year, $204.00 per year = $2,040.00 per 10 years = 100 years of backup electric generation for the cost of the 3 KW turbine and tower. Well, that does it. I'm buying a steam engine when the Whisper 500 fails from it's one year old fan props, "AGAIN". And I'll convert the site to solar PV trackers to make use of the wire and clearing on top of the mountain. The gain in power from a tracker on top of the mountain is greater than the generation per month of the turbine, if I simply move existing panels on the 3 KW fixed array 3, to (home made) trackers on the tower site. There are already five bases for trackers there as anchors for the tower. I can make use of the tower pipe in constructing the trackers. And with three wires running down the mountain, I can have two separate high voltage/low amperage DC sources to the house, sharing neutral.
Back to the 6 KW backup generator. I visualize a unit that has a choice of propane/gasoline, diesel, or steam as the power source. This can be done for less than just a Kestrel e400i high voltage without the tower. Already have the propane/gasoline engine running a 9 KW generator. I'd take off the louzy AC generator and hook the engine by belt to the drive shaft of the new DC generator. Also, the shaft will terminate to a PTO shaft that can hook to any tractor (diesel or gasoline), and I'll tie into the drive shaft with the steam engine. So I can use whatever fuel or tractor that is available, and can add engines through time. The 6 KW back up DC generator will be the Whisper 500 mounted on the ground and the two 1500 watt PMA's from the Missouri Wind General micro turbines. Making use of stuff I already have, and be modular to increase reliability.
2/19/2011 A few days ago I ordered Hugh Piggott's book on Kindle for $5.00 at amazon.com. After reading it over, today, I ordered his US version in print and a 3 meter/1000watt DIY kit from http://www.magnet4less.com/ . I really look forward to winding the coils and building the turbine from scratch. I'll test it with the tower I built for the two Missouri Wind micro-turbines that TOTALLY BOMBED! After reading over Hugh's book, I can see why the PMA with to many blades, totally failed to produce power for me at 51.5 VDC. But in Missouri wind's defense, it will work for a 12 VDC system if all you expect is a few hundred watts in gale force winds..2/24, the kit arrived and I am not impressed with the props. Think I'll carve my own out of wood.
2/28 I ordered the magnets and magnet wire to build one stator and generator to run with one 11 blade 5 foot fan from the failed PMA project. I'll use the 11 blade fan and construct a stator that will start generating 51.5 VDC at a low 200 rpm. I ordered the wire and magnets from http://www.magnet4less.com/ . I ordered the epoxy resin and Kevlar fabric from http://www.uscomposites.com/ . Decided to use Kevlar to reinforce the castings, 5 oz fabric FG-KEV538. Also, after talking with the person at US composites, he recommended the 4 to 1 thick epoxy system as it has the highest temperature rating for staying rigid. The others get soft and droop above temps of 130 degrees, which on a sunny summer day without a breeze is easily possible, in the sun. I just add less hardener to get a slower set time for casting. And the Alum powder to mix in too, for displacing heat. I'm thinking of using an arbor from a brush cutter with sealed bearings for my rotor. If the stock bearings have trouble, I can replace one with a Timken thrust bearing. This setup will have nearly zero friction compared to the trailer hub, and is a lot more bearing than a PMA. I'll add the Oregon part number if I buy it.
3/3 Wound up 6 coils of 19 gage wire for the first Earthbilly Micro Turbine. I should get over 12 coils from one spool of wire. I plan to use two magnet disks with 8 magnets each, instead of the one magnet disk for a 6', 3 blade prop as in Hugh's instructions. Reason, I am using an 11 blade prop to achieve high torque at low rpm and also to self govern high end rpm. Very different from the three blade prop for high rpm power and furreling to stop over rpm. My turbine will not furrel. My experiments with the 11 blade micro turbine and pma indicate high power at low rpm, (charges great at 12 VDC with a 60 VDC stator), and seems to have a limit of about 1000 rpm in the highest wind gales, according to the pma power graph and true output of only 125 watts in 35 MPH wind gusts at 51.5 VDC. Missouri Wind and Solar's 1400 watt 11 blade micro turbine for 48 VDC is only capable of 125 watts full power in 35 MPH wind. I'm trying to use the same fan and create the proper generator. My coils have 272 turns. I can experiment with this stator and fine tune another to achieve the results I want.
11/10/2011 I can't get any high grade balanced steel hubs without buying blade hubs from Missouri Wind and Solar. http://www.mwands.com/ They have the best hubs available.
11/18 I upgraded my two Missouri Wind and Solar 14 magnet turbines with the new Raptor Gen 4 white turbine blades and cut back from 11 blades to one 6 and one 7 blade. Preliminary results are good. Today will be a windy day. At first I installed the 13 blade hub on both turbines. They would start in almost no wind but seemed to get to a speed quickly where the turbulence would make noise and stop generating. My 60 volt stators just need more RPM than the 11 or 13 blade fans will deliver. So I switched to a 6 and a 7 blade. Yesterday the winds were to light to generate but it seemed that the 6 and the 7 blade hubs started about the same and stopped about the same. The bigger difference in them is the 6 blade hub is really a 12 blade hub with 6 blades and is 10" diameter, much larger and heaver than the 7 blade hub, giving the 6 blade hub an advantage in blade base diameter and consequently starting torque per blade to the hub. When I originally took down the tower two days ago after testing with 13 blade hubs on both turbines, I only had the one 6 blade hub and put the tower back up, lower turbine without a fan, and the 6 blade fan on the upper turbine and it definitely made as much power alone as both turbines with 13 blades. Very interesting. So maybe some of my problem with poor generation may be linked to the original 11 blade fans. HOPE TODAY the predicted high wind will prove it. So now I have enough extra blades to build another two turbine tower! If this one finally generates more than 10 second bursts of 500 watts.
I also added two more 6 AWG welding wires down the tower and doubled the wire in the run to the controller. So each turbine has it's own two wires down and separate 6 AWG wires to the controller. The turbine output doesn't combine until it enters the controller 150' away from the top of the tower. NOTE! After two years tower up, there were no twists in the two original 6 AWG welding wires. Well...again, not real impressive power output. They really get spinning and briefly generate enough to export 100-200 watts into the grid for two or three seconds at a time. I turned off the big turbine up on the mountain so any DC generation must come from the two micro turbines. The winds are 15 gusting to 24. I'm getting brief output of 5 amps up to 9 for no more than a second. That is from two combined turbines. Maybe I'll disconnect one just to see what happens. Nope, that didn't help.
11/19 I've tried everything to increase output of the old 60 volt stators in the old style PMA's. Now it's time to switch to the new PMA's. I was hoping to increase the output of the old PMA's and build a new tower for the new PMA's. We will stick with the 6 and 7 blade fans for now. They seem to spin really fast and start easy. Yesterday was really windy, 15 gusting to 24 all day, the turbines rarely stopped spinning, and our all day total; 0.1 KWH from the turbines in the photo above. I just hope the new PMA's have more magnetic flux and will produce power within the RPM's of the fans. There is no visual difference of performance between the 6 and 7 blade fans, remembering the higher moment of inertia/ higher torque per blade of the bigger hub with less blades. FYI I've blown another thousand dollars at Missouri Wind and Solar in order to do this testing. Pardon the pun. There is a lot riding on today's change out of the PMA's.
11/19 Evening. I changed to Missouri Wind and Solar's newest 14 magnet PMA's. I put up the tower with the 6 and 7 blade fans and WOHO!!! it started charging right away. I took down the tower and installed an 11 blade fan on top and a 13 blade fan on the lower turbine and put it back up. It did not work as well although the fans almost never stopped spinning. I took the tower down again after a couple hours of observation and reinstalled the 6 and 7 blade fans and WOHO!!! it worked great! Finally, the micro turbines work great!!! Thanks to Jeff of Missouri Wind and Solar and his relentless drive to perfect the microturbines!! Jeff's own design and manufacturing of the blades and the new PMA's work great!
This is such a relief. I've been working so hard trying to get generation from the old turbines and all along the regular PMA's have been the problem. It looks like the 7 blade fan is minimum required to turn the new MOWIND PMA. The 7 starts and spins easily while the 6 only starts when generation wind is blowing. Guess I'll take down the tower one more time and put the 7 on top and try the 9 on the lower turbine. Haven't tried the 9 yet. The 11 and 13 seem to slow for 52VDC.
12/27/2011 I wired the two turbines up with separate wires all the way to the controller and installed two amp meters so I can test different hubs against each other. I tested the 6 against the 7 blade, 7 against the 9 blade, 9 against the 11 blade and the 11 against the 13 blade hubs with MOWIND&SOLAR latest blades. Every time I got better performance and startup until I got to the 11 against the 13. The 13 had better startup but worse performance with my 48VDC charging. So the 11 blade hubs had the best side by side performance of all blade hubs tested with the 48VDC PMA. Side by side comparison!
And at the end of this year the Whisper 500 is still cranking out power. I briefly hooked the 240 VAC 3 phase from the Whisper 500 to a heavy duty rectifier and ran it directly into one of my Sunny Boy 3000 inverters set to turbine mode and it looks like it may work better than the Whisper 500 charge controller with the transformer. Now I am considering phasing out the Whisper controller to another Sunny Boy inverter and overvoltage locking device. It sure seemed to generate better wattage! But for now I returned the SB to the solar panels.
09/10/2012 I finally took down the tower with our two micro turbines. It must not be high enough at 46 feet to reach a good flow of wind. The turbines never made more than 0.1 KWH in a single day, and that is only about two days a year. In comparison, the same day the Whisper 500 made 12 KWH.
For the latest developments in 2012
Currently building dual axis tracker with kit from Windy Nation to rack 6 230W panels and run them as two strings to our Midnight Solar Classic charge controller. This is our first solar not run through a Sunny Boy inverter, (inoursystem), and intended to further demonstrate differences in charge architectures to visitors touring our project. And a great use for the Classic we bought to run micro-turbines and found out there was so little generation we took the whole dual turbine tower down. We used the Classic for a while on our Whisper 500. It worked great and gave us a way to watch the output on our computer, but in the end I built a whole new charge control for the Whisper, because the original SWWP controller was really poor and broken most of the time. FYI, the Classic and the NES controller withstood lightning strikes that blew out our SWWP controller and both of our stock Wattsun Tracker electronics. I installed all new components for charge control into the SWWP Whisper 500 transformer box.
New layout of Whisper 500 turbine charge control. The Midnight Solar Classic unit is mounted for control of our current PV project as yet not completed. The inside showing layout of bridge rectifier, Flexcharge controller, and solenoid for external load control.
Note the bridge rectifier. A very heavy duty unit made for DC welding. This Flexcharge by NES is tried and true, the controller has withstood test of lightning and time controlling our micro-turbines for 4 years. It watches battery voltage and connects the original SWWP load dump resistors directly into the turbine AND battery bank when voltage goes over 56.5 VDC. This configuration protects my batteries from anything that might cause voltage spikes from the turbine AND from any other sources. It also allows the turbine to spin and not be subject to extreme shorting out as if turbine were directly hooked to the resistance load by its self, which is similar to shorting out the turbine with a brake. No doubt this architecture is easier on the yolk and brushes inside the turbine. We have had failures of these turbine parts in the past. Controlling battery voltage is so important, we plan a second, (backup), controller and separate load dump. Maybe two smaller dumps set to slightly different parameters so the load dump works in smaller wattage increment stages. Using the redundant systems as a failsafe at the same time.
The heavy duty solenoid. Battery and turbine combined on one side and load dump on the other side. They connect only when voltage goes over 56.5 VDC.
We need to set any possible charge parameters within the system below this value by at least 0.5 volts, so the load dump doesn't connect during boost, equalize, or float.
I have noticed if grid power fails during sunny conditions, the battery voltage may spike in the high, (60's), until the SI's and SB's respond. This configuration seems to control the voltage spike much better, and gives the SMA equipment time to react to grid failure.
December 26, 2012.
This is as good as generation gets with a Whisper 500 3.2 KW wind turbine in real life. Our storm winds have been 25 MPH, gusting to 40 MPH all night. Still, there are moments of low wind as well. 10.9 KWH, all from the Whisper turbine, at 7:19 am. In truth there are moments of up to 3 KW generation from the turbine, but SMA grid tie equipment tends to average the peaks and troughs of generation somewhat into real grid feed data. Long story short, in real life under perfect natural wind conditions, with winds that sometimes furl the turbine, expect 1.5 KWH/hour generation. Here is where a Kestrel 400 would be superior. No losses to furling.
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