Turquoise Energy Newsletter #162 - November 2021
Turquoise Energy News #162
covering November 2021 (Posted December 4th 2021)
Lawnhill BC Canada - by Craig Carmichael

www.TurquoiseEnergy.com = www.ElectricCaik.com = www.ElectricHubcap.com

Feature: Efficient, Quiet, Low-Speed ("Savonius" flavor) "Wind Wall" Windplant for Light to High Winds

Month In "Brief" (Project Summaries etc.)
  - Wind Wall: New design has it all: low noise, high power capture (40%?), power in low winds, bird grille, to be made of abundant recycled PP plastic. - New Grid Tie Solar Inverters - Handheld Bandsaw Mill Kit Status - At Last: A Superior way to fasten magnets to an axial flux rotor!

In Passing (Miscellaneous topics, editorial comments & opinionated rants)
 - Grass Building Insulation (R4.2 per inch) - Smol Thots - ESD

- Detailed Project Reports -

Electric Transport - Electric Hubcap Motor Systems
* "Low Rolling Resistance Tires" -- So Called? -- An Adverse Report

Other "Green" & Electric Equipment Projects (no reports)

Electricity Generation
* "Wind Wall" with New "Savonius" Rotor Design, Vanes, "Darrieus" level performance, even in low winds
 - "Wind Jammer" rotors - Mini Wind Tunnel - better flat "air scoops" rotor - new "compound rotor" design better yet - These plus stationary wind guide "vanes" improve performance to "Darrieus" levels: around 40% instead of under 20%.
* My Solar Power System:
 - New Grid Tie Solar Inverters: One installed
 - Power Outage and "Off-Grid" System Improvements
 - Daily/Monthly Solar Production log et cetera - Monthly Summaries and Estimates


November in Brief

I've shown views of the broad beach below my home at low tide before.
This time I thought I'd try for high tide in a storm with a new moon, November
5th. (Drying foam says I missed highest tide by a 1/2 an hour or so.)
Big logs were rolling and tossing around. Surely there is power in waves!







It's nice to know that in all the inflation some things have been getting cheaper:
Solar PV, Wind and maybe Geothermal power.
(When I was a kid in Edmonton, CH4 "natural" gas was dirt cheap. Now it's gassing out of the
former permafrost in the Arctic, but in Europe the winter heating supply is in question.
But it was never "sustainable".)


   Early in the month I had a short vision one night featuring my warmest winter jackets, then snow. I figured it must be serious for it to have been brought up. Gosh, could it be it would it even be hard to get from the house to the far firewood shed? It was like that in Victoria in 1996.
   I have a large hallway closet with plywood walls intended for firewood. I don't like to keep firewood in the house and had used it for general storage instead, but I emptied it of its riffraff and filled it with the wood from part of my new firewood shed, carrying it up in bulk in a trailer behind the lawn tractor.
   About a week later the forecast was for snow all across Canada & USA, and there was snow in some places. On the 9th some news said even North Africa was getting a dusting of it. I suspect that the highway will be impassable for a time. Are we going to have long power outages going along with this? It seems more than possible around here. By the end of the month nothing special had happened in Northern BC. (It did start snowing on the evening of December 1st with more the next day. Still not unusual.)

   Oh, there was one thing: on the 8th there was a strong wind and the power failed. Trees often fall across the power lines in storms. Nothing special in that either, but I tried a few "off grid" things out - running the freezer and the microwave, and monitoring power and the little charging the DC system was capable of in dark clouds - and I planned some improvements to my solar systems, especially DPDT switches to make it simple to switch solar panels from the grid tie inverters to the DC power system. This plan was rudely interrupted before I got anything much done by the following:


VAWT (Vertical Axis Wind Turbine) - the Wind Wall

   The month was proceeding smoothly when on the 10th Kamil dropped by with an idea for making a windplant from a fishing float. I didn't think much of it but I had just seen in youtube suggestions the idea of a "Wind Wall", a frame with rotors on the inside. An artist had started it, I believe, with rotors linked together that formed pretty patterns as they turned. Then Robert Murray-Smith had made one filled with small Savonius rotors connected to small generators in a compartment below. We watched the video.
Robert Murray-Smith's Wind Wall - from his video


(I also found a gigantic megawatts "wind wall" computer concept set on pillars over the sea, which seemed totally unrealistic. If it had at least been floating it could have aimed itself into the wind.)
   I said winds usually blew straight up my driveway from the ocean so my "wind wall" didn't need to turn to get most of the wind, and Perry had the great idea to mount the unit on the gate, right in the best wind, but thus it would swing out of the way with the gate for cars.

   Of course I had some ideas of my own tucked away in the back of my mind too, and I thought again after the power failure of how little solar power there is here in the winter. So somehow I got sucked into this new project, unwanted and seemingly not very promising in the big picture. I made a tall, thin Savonius rotor (why a bunch of short ones?) and stood it in front of my big box fan. Of course it turned, more or less.

   Then I cut it down to half the height and I made a mini wind tunnel: a box the size of the fan from scraps of plywood, open at both ends. I put a bearing in a hole at the bottom and drilled a hole for the shaft to stick through at the top. Every rotor tested would then be mounted in exactly the same place relative to the fan and tunnel.

   I measured the Savonius rotor at 80 RPM. I also measured the wind speed in the tunnel with the fan on "high" as 3.1 meters/second, which is a little below where most propeller and Darrieus windplants even start turning. So I was testing for the more frequent case of light winds instead of rare storms.
   "Light winds capable" was the target - a few tens of watts often instead of hundreds of watts rarely.


   Then I thought I'd search on line and see if there was anything better. I found a paper that mentioned a "slightly better" shape and had a diagram of it. I printed the diagram. "Full page" was just the right size for the plastic PVC pipe I was using. I heated the pipe in the oven and bent it to the right shape to fit on the pieces of wood I cut by cutting out and tracing the drawing. It turned at 82 RPM. But the first rotor was only 7 inches diameter while the new one was 10 inches, so the same RPM actually represented considerably more outer rim speed and more power.

   (With the black cable tie on the shaft you can count the "R"s. On the left top is an "M" meter. You can't find RPM without an "R" counter and an "M" meter. Luckily it didn't get too fast to count "R"s by eye for 30 seconds.)


   But, I thought, the new shape was flat both on the back (the main part of the advantage) and the front - a disadvantage. The front would have more air resistance returning upwind to the "top" of the power cycle. I added a second layer (screwed on alium. sheets) that made it a rounded front face again, which created a further improved "Savonius" rotor that turned at 90 RPM. That seemed rather thrilling. How much - or was it how little - creative thought had been given to Savonius rotor shapes in the last 100 years or so?
   The profile now had "thickness", like an airplane wing with a different top surface shape than the bottom. I have never seen that for a "Savonius" type rotor before.


   Next I put a stationary vane in to direct the wind toward the side of the rotor being pushed downwind, and away from the side pushing its way back upwind. This also concentrated the wind and increased its speed. This time the rotor hit 160 RPM, and took some actual bit of force pinching the shaft to slow it down much. Potential tens of watts, I think. With a couple of vanes it hit 172 RPM. The vanes would of course be built into the frame of the wind wall. (Further testing might optimize vane sizes, placements and shapes, but even one flat board works wonders!)


   All this development occupied only about 10 days. I made a somewhat
long and rambling video  Evolution of a Windplant  and put it on Youtube:
https://youtu.be/S8c06FUBrpg



The Hayes Hybrid Rotor Setup. U of Utah wind tunnel  
   The actual subject of the same paper was about making and testing a hybrid rotor, where the Savonius bottom half was the means to start the Darrieus top half spinning, even in low winds, thus harvesting power with something toward the efficiency of a Darrieus rotor (~40%) at catching the wind's energy. (Straight blade Darrieus rotors only work once they are spinning, so they need some way to start them.)
   Up to this point doing this had also become my idea. However, it seems a typical "good" Savonius rotor is about 18-20% efficient. The first better shape should thus have been over 20%. My third shape then was surely at least 25%. When I added the vane and nearly doubled the RPM, I felt I must have achieved at least similar efficiency to the Darrieus type, around 40%, with the improved Savonius type of rotor and the vane.

   So then!, why would I make a Darrieus or hybrid rotor at all? Since the "wind jammer" types turn a little slower than the wind speed instead of 4-6 times faster, they will surely be far quieter.
   Suddenly there was nothing more that needed to be developed. No figuring out the best Darrieus shapes and configuration, or how to make the optimum hybrid to get best performance out of both parts of the rotor. An improved "Savonius" "wind wall" with vanes had it all!


   A viable "Wind Wall" product would be worth selling, and I started thinking seriously about how to produce them on at least a limited production basis - probably formed out of recycled polypropylene fish nets, which have been collected off beaches here recently, representing thousands of pounds of free material.
   The tricky part would be the electric generators themselves. My "Improved Piggott Alternators" would be great, but overkill. (except maybe in a hurricane!) I ordered some small generators from China, but the speed will probably have to be geared up higher for them - that's noise and inefficiency. Flat or poly-V belts are supposed to be highly efficient and might work well, with little noise.

   There was another rotor shape variation I wanted to try. It would be a simplification if a single sheet rotor surface could be used. I tried it on December 1st. It didn't work as well. I think, like the airplane wing, I have discovered the basic best profile in the "compound" rotor and future profiles are likely to be variations on this essential theme.

   I also got an oven from the refuse station, to put the molds into to melt the PP into the desired shapes. I intend to cut off the back and make it a much deeper insulated oven box, so that it will hold molds at least 5 feet long. It is 23 inches wide. (I'll use it outside the laundry room and run the 230V power cord from the dryer plug out through the window.) The idea of an oven large enough to hold any mold I make, and using the fishnets that only have to be cut to fit in the mold instead of shredded, should revolutionize the way I can make flat-ish plastic components. But for starters I'll just use the oven as-is and make first the rotor molds that will fit into it. (Or I may just open the windows and use my kitchen oven for the first one or two.)

   Then I'll have to try making the alium. molds and actually molding the plastic in them. (The PP plastic won't stick to alium. once it's cooled.) I intend that they'll be a bottom "box" piece with sides to hold the plastic, and a top "lid" piece that fits just inside it. Then I'll have clamps with springs that push the lid down into the box, and as the plastic melts, the springs will push them more and more closed until the plastic is solid with no air gaps, and it won't compress any farther. The thickness will be controlled by weighing the plastic before putting it in. (If necessary there can be end stops that stop further compaction together of the pieces at the desired thickness. These may be in the mold, or adjustable "end stop" bolts on the clamps.)


New Grid Tie Solar Inverters

   I didn't have enough grid ties for all the solar panels in summer sun, and I wasn't happy with the way the present ones kept jumping back to zero and only gradually ramping up again when a cloud came along. By the time they were back to full power, another cloud would come and it would start all over again. So when I ordered 3 new grid ties they were a different brand, 700 watts rated.
   At long last they arrived on the 29. On the last day of the month I replaced the one in the cabin with a new one to see what improvement there might be. Soon after the cord to the cabin came unplugged and so it was off all day. The next day snow covered the panels, and they were still half covered on the 4th. Well, at some point I'll be able to compare them and see if the improvement is 2% or 20%.


Handheld Bandsaw Mill Kit Status

On the 19th I took the mill to Wayne to take and send pictures to the engineer. Then I typed up the notes I had made when I was sawing and sent them along with the CAD drawings of the plates.
   In the meantime the stainless steel plates had been waterjet cut and were mailed to me. The price was rather shocking for such a small, simple job, and made me all the more determined to get the CNC table and the HHO torch running in order to be able to do such things for myself.


At Last: A Superior way to fasten magnets to an axial flux rotor!

   Eureka! After repeatedly thinking about this problem since 2008, I woke up on December 4th with a better answer. The problem of course is the centrifugal forces on the magnets on a spinning rotor. I epoxy them on, and I have sometimes wrapped them with PP webbing and epoxied that on. But I have had glued-on magnets fly off rotors with destructive force when a motor gets spinning too fast. And I've had them come off commercial motors, too (a lawnmower motor and my lawn tractor starter motor). A few months ago I came up with the idea to drill holes in the rotor so 'plugs' of epoxy reach through to the other side to help hold, and also epoxying half way up the sides of the magnets.

   Now it occurs to me that the best and also easiest thing would be to rough up the surface of the rotor with an angle grinder where each magnet is to sit - maybe even dig in some grooves. There's just about no way the epoxy could lose its grip on all those rough surfaces.
   Then similarly rough up the underside of each magnet, even going through the protective layers. Once it's epoxied onto the rotor it's protected again.
   To be even more sure one would apply the epoxy also around the sides, which would ooze down before it sets and become a thick skin around the magnet where it meets the rotor. Roughing up the sides of the magnets a bit along with the bottom might be a good idea too. So might a second coat once the first has set.

   I have previously broken rectangular magnets loose from my rotors by twisting them with a 15 inch crescent wrench. With such a technique as this, I could see the whole magnet breaking into fragments as one twisted, without the epoxy ever breaking off. I would think the large rotors for the planned unipolar Electric Hubcap motor should be good for about 3000 RPM instead of 2000, or 2500 as I was more opimisticly hoping for! That will mean it can be geared down that much more and have 1.2 to 1.5 times more torque and power at a given vehicle speed. or that the top vehicle speed can be raised that much.

   If I ever finally get to making the motors, they're going to be really great ones!



In Passing
(Miscellaneous topics, editorial comments & opinionated rants)


Grass Building Insulation

Missed the Eelgrass

   Excited by hearing that eelgrass makes great building insulation and thinking of my cabin, on the 3rd I walked almost to the far end of the beach looking for some, a couple of kilometers(?), and there were some small drifts of it near the far end, high up on the beach and in a spot I could park the utility trailer near. I thought I'd grab it the next day before the tides got too high and it was washed away at high tide. But I miscalculated. The 4th was in fact the day of the new moon and hence highest tides per fortnight, and I arrived with car and trailer and Perry almost at high tide. Also it was stormy and there were big waves washing in. We managed to get 3 wheelbarrow loads into the trailer before the water got too high for comfort and even the highest-up eelgrass started washing away before our eyes. Not much of a load! Anyway there was a lot of kelp in it too, and perhaps it would best be used as mulch on the garden. Some big piles washed in later, closer to home, but by then I didn't want it.


Forget the Eelgrass... How About Lawn Grass?

   Having looked up eelgrass, I went farther and looked at just grass grass. Sure enough, a company is processing that into batts for insulation, too. The "R" value is around 4.26 per inch, which is 27% better than fiberglass. (~3.3. I never did get an exact figure for eelgrass - perhaps 3.5?) That would mean R 15 in a "2 by 4" wall (actually 3.5 inch) and R 23.5 in a "2 by 6" wall (5.5 inch). With such an improvement, might we return to making "2 by 4" walls as was done up until... hmm, 1980 or so, was it? Around that time exterior walls started being made of 2 by 6es to get a higher "R" value than R12 with fiberglass.

   What processing does it need? Those making it into batts were first "de-juicing" it to extract "the cellulose". Their pictures were pretty tiny, but to me the batts looked like they were made of bits of straw, so I suspect the process wasn't very involved and that simply drying it would do almost the same. Then they added jute and PETE. It was said the PETE could be replaced by PLA. Starch was also mentioned, and borate. (More info: www.GrassInsulation.com/technical )

   I can cut grass from the lawn any time during the summer! (There's a bagger for the lawn tractor that I've never used but certainly could. With luck I can even dry it.)
   I started to think that something similar might be accomplished by installing grass between wall studs or ceiling rafters and then spraying it with something. Or maybe make a horizontal form, lay the grass in it and spray it to make batts? The spray substance would be expected to bind the grass into a matt or batt, and to provide anti-flame and anti-mildew properties. But does it need to be made "less green" by adding plasticiser or anything at all?
   If the wall is dry it shouldn't rot. And does it even need to be "fireproof"? A gyproc wall with grass insulation would surely be far better fire protection than the cedar board walls with fiberglass insulation in my garage! (Now there's scary construction for fire safety, and which has been bothering me since I bought the house!) The safety is in the gyproc, also in the alium. exterior of my cabin. It would be hard for a fire to get into the wall. I could do small fiberglass areas around potential sources of heat: electrical boxes and hot water pipes.

   I looked on line. Gyproc is considered an adequate thermal barrier for flammable "spray foam" insulation. So it should likewise be considered sufficient for grass even if flammable.
   I think maybe I'll try that: raw but fully dried grass for cabin wall insulation. Not in the ceiling with open rafters to be sure, but in the outer walls with gyproc and alium protection. That would cut the need for fiberglass way down and provide better insulation.


Cellulose Fiber Insulation

   To continue with the topic, I've mentioned eelgrass and grass grass building insulation. In a more "conventional" vein, did you know that compared to fiberglass insulation, recycled cellulose fiber insulation has a higher "R" value per inch, isn't itchy to install (but is dusty), doesn't attract pests, rot or mold, is cheaper and has better fire retardant properties. The explanation for this last rather unintuitive feature is that when a fire reaches the inside of a wall, fiberglass will shrivel away from a flame, allowing it to spread into the cavity. Cellulose fiber doesn't and as loose fill it fills the entire cavity, and so the flame has to char it bit by bit to get into the wall.
   This was in fact tested by building 3 identical "large outhouses". One had no insulation, one had fiberglass, and the third cellulose fiber. All three were lit on fire at the same time. The uninsulated one burned down in (I am going by memory and rounding off) 40 minutes, the fiberglass one in about 60 minutes and the cellulose fiber one in 80. I was impressed. The video is on youtube somewhere. (Could grass be better than one might expect, too?)



Smol Thots

* On the 21st, big news. My friend Tom phoned and said there was no food - or gasoline - in Victoria (BC). He was probably exaggerating, but there was petrol rationing, and a week later he sent a picture of big empty shelves in Wallmart there. This sort of trouble has been coming on for years with overpopulation, the economic disenfranchisement of the public at large, the increasingly wild weather destroying crops and manifold disruptions of supply routes.
   But exactly how and when it would and will unfold, the actual events in any given area, are bound to be a surprise. With the most common weather word lately in play, "unprecedented" rains and flooding created washouts on all the major highways in and out of Vancouver/"the lower mainland" of BC along with the rail lines and fuel pipeline. This is or was also BC's biggest farm and food belt. Since Vancouver Island's transportation and supplies also come through the lower mainland, Victoria and the whole island is also cut off. Tom's family has only a month's food on hand, and they are doubtless more prepared than most. I trust essentials will be restored within a month - for now - but the damage to roads is severe, and more heavy rain savaged repair and recovery work.

* Other parts of the world are having their own troubles. China's industrial northeast, already short of fuel, has had severe blizzards and so have many parts of the Northern hemisphere. There was even snow in Tunisia (and Texas again), and more floods in Soggy Arabia - and places in South America where in the past it has rarely and lightly rained. And I'm sure I've left a few things and places out.

* Presently things are still fine in the BC North. Highway 16 (and I believe a rail line) is still open to Alberta and the East, where many of our supplies come from. The ferry to Haida Gwaii is still running. But one can also visualize many "not unlikely" problems that could close long, thin arteries through the mountains. The highway from Prince George to Prince Rupert is often closed owing to mudslides or deep snow.
   But "Dairyland" is in the lower mainland and "Island Farms" is in Victoria, and as I have lamented before about the laws eliminating local dairy farming, there are almost no dairy cows anywhere else. It is inevitable that that if North-South transportation is virtually cut, or the dairy farms or plants are too flooded out, northern BC will surely soon have no milk products from those drowned cows in Abbotsford - not for many months if ever. (So far no problems at the groceries here, but grocery stores on the mainland have been shopped out by people stocking up.)

* Africa continues to have by far the lowest rates of Covid in the world and a far lower death rate from it. Most African nations don't lock people down or shut down their economies or force citizens to wear masks, and have no money for vaccines, hospital treatments, and so on. But lots of Africans get enough vitamin D (from sunshine) to be more resistant to viruses, and are outdoors in the warmth a lot. Their buildings probably don't have recirculating air to spread whatever someone breathes out to the rest of the building. Plus Africans tend to be younger, and Covid is mainly harmful in proportion to age. They also have ready access to free or low cost Ivermectin and hydroxychloroquine owing to the presence of a multitude of parasitic infections endemic to that continent. It seems all these things add up to "no Covid".
   But why are the rest of us not being advised about getting sufficient vitamin D to ward off cancer and Covid virus? Why do we not have Ivermectin and hydroxychloroquine "over the counter" in our drug stores? Why are we so often being told to stay indoors instead of getting out in the healthy outdoors? Why are we being told to wear masks after they have been demonstrated in studies to be virtually ineffective? What happened to "follow the science"? And why is any of it "government edicts" instead of "medical advice"?

* The new "omicron" (AKA "moronic") variety of Covid discovered in South Africa appears to have already been in many other places around the world - it was just identified there first. However, it seems it is very mild, with just "feeling really tired" for a couple of days, no hospital admissions and no deaths.

* It is said that government governs by the consent of the governed. I saw a new "declaration?" going around on the internet: "Withdrawal of consent to be governed by [your] government. [fill in the name of the government - your nation, your province or state, ... Signed by - you.]
   If a few people fill out such a declaration, they are probably flakes. If millions do, when it becomes a considerable portion of the population, the legitimacy of that government is probably in serious question and if it is incapable of meaningful change, alternatives to the "status quo" should be diligently sought after.

* Michael Dowd has a great two-part video set on youtube, "Collapse in a Nutshell" and "Overshoot in a Nutshell" - both subtitled "Understanding Our Predicament". He defines a "predicament" as a situation incabable of solution that one must live with and adjust to. As it is much too late to prevent severe climate and earth changes, it is a "predicament" rather than a "problem".
   Whenever a civilization starts to degrade its environment, when nature can't renew and keep up with what is being done, it is in "overshoot". Without managing its population to maintain a sustainable level and taking immediate corrective actions at the first appearance of environmental overshoot, that civilization is doomed to collapse. The population will continue to grow and the environment will become more and more degraded, more and more rapidly, until vital resources have been fully expended and the civilization collapses with great loss of life. Dowd quotes someone as saying "Civilizations start with a forest and end with a desert."

* I was surprised to learn that in the last 4000 years, at least 88 civilizations - that all thought they were "eternal" if they gave it any thought at all - have arisen, thrived for 200-400 years, overshot and ruined their environments with too large a population, and quickly afallen. Only when our ambitions to espouse the root values of being human and humane, to be fair and considerate to all for today and for the grandchildrens' grandchildren into the indefinite future, become embedded into our culture and way of living, will we learn how to create sustainable societies.
[reminder? 7corevalues.org ]

* Globally we have entered "overshoot", and with the advances in technology many global "tipping points" of environmental and ecological nature are already behind us and the consequences can't be avoided. We will have to live and die with them. Some would pinpoint 1974 as the year we started going too far, when we started using resources faster than nature was replenishing them. I would put it about a decade earlier. Dowd points to charts of things that go "hockey stick" - suddenly rising up - from about 1950 onward.

Dowd's two 1/2 hour videos are well worth watching!

ESD
(Eccentric Silliness Department)



* The kitchen cabinet place manufactured several items, but most of their efforts were counter productive.

* Their installers guaranteed their jobs to be "counterfit".

* Pharmaceutical school adage: "A patient cured is a customer lost."

* They call it a golf "tee", obviously meaning "T". But isn't it really more of a "Y"? (or is it?)

* Last year my vision was 20-20. This year it's only 20-21.

* Bagger, beggar, bigger, bogger, bugger... Which word is out of place?
   Answer: D. All of the above. None of them have anything to do with each other, although I'm not sure what a "bogger" is.

* "Find" is the present tense of "found". But it is claimed that Samuel de Champlain "founded" Quebec. Since "ed" makes a verb past tense, the present tense must be "found". So on his way up the St. Lawrence Champlain says, "Here I found Quebec." But if he found it, it must have already been there to find. So how could he be the founder? Somewhere it doesn't make logical sense... I've foundered!

   "in depth reports" for each project are below. I hope they may be useful to anyone who wants to get into a similar project, to glean ideas for how something might be done, as well as things that might have been tried, or just thought of and not tried... and even of how not to do something - why it didn't work or proved impractical. Sometimes they set out inventive thoughts almost as they occur - and are the actual organization and elaboration in writing of those thoughts. They are thus partly a diary and are not extensively proof-read for literary perfection, consistency, completeness and elimination of duplications before publication. I hope they may add to the body of wisdom for other researchers and developers to help them find more productive paths and avoid potential pitfalls and dead ends.


Electric Transport



"Low Rolling Resistance Tires" -- So Called? -- A Report

   In the summer I was very pleased with my new Bridgestone Ecopia low rolling resistance tires. But when the temperatures started dropping to 12 or 15°C or below - typical for 3/4 of the year - they turned into werewolves. Rolling resistance shot up like a rocket. Instead of say 1.2 to 1.3 kilometers for each percent of battery usage at 80 KmPH highway speeds, it dropped to maybe .9 or so - a 25 to 30% drop.
   Instead of hitting town with 82% battery as I had in the summer, it was more like 72%, more percent drop than kilometers driven! And instead of getting home from there with 56-61% battery remaining, it was down often to barely over 40%. To drive to Port Clements and back without hitting the low battery warning at 20% - or perhaps even hitting 00% if I was careless - I had to drive the highways at about 55 to 70 KmPH instead of 80+. I don't think it's ever been that bad before. So it's taking much longer to do that drive, and with pulling over to let others pass. It's well that the highway is less than busy, but it doesn't give electric cars a good rap!

   I went from being very happy to wishing I hadn't said I didn't want to keep the old "Ironman all season" tires. Very disappointing! They dropped in the winter too (which was why I wanted to try something different in the first place), but not as badly as the "Ecopias" did. 1.0 to 1.05 kilometers per percent of battery drop seemed to be typical in colder weather, but not under 1.0 except in snow.
   I must conclude that the people giving the glowing reports on the Ecopias must live in California or other warm weather climate zones.

   Then it got colder. At 2° the performance actually seemed to improve, sometimes - to about what the old tires did. Now if typical temperatures around here weren't usually in between.

   Interesting... in the last few days, I've twice gone out to the car (plugged in) and found the heat on! I've never seen that before. So it does do preheat - but when it wants to, not when I do.




Other "Green" & Electric Equipment Projects


CNC Table

HHO Gas Torch

[4th] In a video 'Rulof Fai da Te' (Italian, = "Rulof DIY" AKA 'Rulof Maker') showed making an HHO generator and torch using 3 cylinders of water. In this one could blow into one through a tube and pressurize the water, making a fiercer flame. Much was visual but I'm sure I missed some details in his Italian presentation. He showed quickly cutting through some can - I think it was a steel spray can.

   Raising the HHO gas pressure, or perhaps instead adding air or excess oxygen into the torch flame, might be a perfect thing to do for cutting thicker steel. For adding oxygen, instead of costly welders' tanks, one might make a water hydrolyser that separates the oxygen from the hydrogen and discard the hydrogen?
   (Conversely, if one was say trying to melt down copper or silver, extra hydrogen could be used instead, to make it a non-oxidizing flame?)

   Either way one would need a two input torch to mix in the extra gas. I just ordered a one-input one. Oops!



Electricity Generation

Wind Wall
Rememberance Day sunflower. (After      
that day the frost and damp started to get to it.)
[10th & 11th - Rememberance day! "The Great War", "WW I", "The War to End All Wars", ended 103 years ago this month. I'll bet that no one alive today ever met and would remember anyone who died in that war.]

   I had just seen a couple of "wind wall" titles as youtube "suggestions". I hadn't watched the videos, but the idea seemed intriguing somehow. One by Robert Murray-Smith had several Savonius rotors beside each other on a common frame. In a sense each rotor was a separate windplant. I thought it might be less unwieldy than a big propeller, especially with the frame around the outside. One could put a screen or grille over the front and rear to keep the birds out. (wouldn't want their bodies - or nests - jamming the rotors, after all!)
   Furthermore, one could extend the frame front and rear with wood at angles to form a square sort of venturi duct, speeding up the wind where it hit the rotors and hence providing more power in lower winds - as I have wanted to try for some time. (The difficulty of the compound curves for a round propeller windplant venturi kept me from making one. A square venturi would be much easier!) Furthermore, individual "slats" could deflect air from the "wrong" sides of each rotor to the desired side, a good way to increase the effectiveness of most "VAWT" windplants. Thus each rotor column could have its own venturi section within the outer venturi, easily attached to the outer frame at top and bottom.

   Kamil, living "off grid" and wanting wind power, came over and knowing nothing of my thoughts showed me a fishing float he had found, and said "If we cut it Here and Here and heat the plastic and twist it, and do that all around, it could be a wind turbine. I didn't really think much of the idea per se. OTOH I am distressed at the tiny amount of solar on bad days in winter here in the north compared to the minimum daily needs for the house, and so I started thinking... (oh, no, not thinking!)
   We watched a couple of the videos. "Stepper motors" were mentioned as generators. I had some. (I'm not convinced they're very good for that application, but they're a start.)
   There were objections that the wall (in spite of being made up of multiple VAWTs) was aimed in one direction. I said the wind usually came off the water at Kamil's, and at my place it usually blasts straight up the driveway, and so it wouldn't need to pivot. Perry said then it (mine) could be mounted on the driveway gate. That seemed brilliant. The gate was in almost the right place for maximum wind, and it would all swing out of the way for cars to pass.
   I decided to build a roughly one square meter wind wall. If it was good but insufficient, one could add more wall sections.

   I took 4 of the 8 pieces of PVC pipe that had made up my previous VAWT, sitting unused outside the door of the shop all this time, unscrewed them from the wood and put them in the oven. The oven always turns itself to 350°F, and I casually just left it there. It was much too hot. Except for the first one I pulled out, the pieces bubbled up, turned a brownish color and stank up the house. (What was I using before... 250°F?) Then they took much to long to cool and harden again - back to their original 1/2 round shape, and I had to trade simple leather gloves for oven mitts to hold them against the cylinder. (And nothing cured the fact that I had originally bought pipe with holes in it.)

[12th] I made a template of two overlapping circles with a compass for the simplest Savonius windplant rotor, then cut one out of plywood. I traced out 4 more from that and made the first column for the wall - two sets of rotors set at 90° from each other. I didn't see any good reason for making 6 short rotors in each column. It seemed to me that that was just more, smaller parts that would catch the same amount of wind.
   I figured I'd have the motors (generators) in a housing at the top, pointing down, and simple bearings at the bottom. Hopefully rain and salty spray would leave the motors alone and drip down on cheap bearings instead. Another change would be to have each pair of rotor columns counter-rotating WRT each other. having them all going the same way means the air columns are "fighting" each other instead of reinforcing, and would require twice as many, thinner, inner "venturi" air guides.

[13th] I also wondered whether the simple semi-circle "Savonius" rotors were anything like as efficient as they could be. Why not find one with "the best" profile? I did a web search for "most efficient Savonius rotor". The first thing that became apparent was that most of them had a substantially smaller overlap between "buckets" than my 50% (which somehow I thought I remembered as being "typical" from long ago).


   Then I ran across a paper by T. Letcher of trials done at Ohio State University, titled Small Scale Wind Turbines Optimized for Low Wind Speeds. (Undated but with references as late as 2009) It specificly aimed to create a smaller VAWT design that would be the most efficient at low wind speeds. The Savonius was the sure starter in low winds, but the Darrieus is more effective, harvesting up to 40% of the passing wind's energy instead of 19%. So they made a hybrid: the bottom half was a two piece Savonius and the top half was a 3-blade Darrieus. (So ~30% efficient?)

   It seemed to me that getting near 30% of the wind's power with half being of each rotor type, and optimized for low wind speeds, was a goal more worth aiming at rather than just getting 18-20% with all Savoniuses, and I studied the paper in detail.

   "In for a penny, in for a pound!" So much for keeping it simple!

   The discussion continued with a couple of variations of Savonius and mention of another "slightly" more efficient one with a different "bucket" shape (than a split pipe). They didn't make it because "it would have been hard to produce". It didn't look hard to me. The "buckets" were the same shape as I had made previously in my earlier designs. I tried it for the next rotor(s).

   They rejected the idea of directing the air onto the right sides of the rotors and away from the wrong sides to improve performance, because such directors would have to be aimed depending on the wind direction. In this 'wind wall' idea I'll use it because it'll be simple and when there's a good wind it's usually coming straight up my driveway from the east southeast.

   Then they moved on to the Darrieus rotors on the same shaft. They tried out three airfoil shapes, two symmetrical and ending with the asymmetrical "S2027". They tried 3", 4.5" and 6" blade widths. It's easy to see why an unsymmetrical blade will work better: The blades go around in a circle, not in a straight line, so the curved blade is the one cutting straight through the air. Indeed the 6" symmetrical blades performed poorly in the small diameter rotor. They would be "plowing" through a lot of air.
   The team also tried (or at least mentioned) different blade angles. Since the blade angle does a complete circle as the rotor does, I don't expect the angle relative to the direction of travel makes a large difference, and they only showed results for in-line blades, 0°.
   They also tried different diameters to set the blades at. This is not only important relative to blade width and overall wind cross section to sweep, but as a relationship between the Darrieus blades which perform best going faster than the wind speed, and the Savonius rotors which perform best at a little under the wind speed. If the Darrieus diameter is double that of the Savonius on the same shaft, and the Savonius is going 3/4 of the wind speed, the Darius blades will be going 1.5 x. Hmm... on looking up a general rotor performance chart, the Darrieus should be turning around 6 times the windspeed to extract maximum energy! That suggests that it should be 6 times the diameter of the Savonius? I hadn't realized it was so high. That's certainly not how their unit looks, and a 48 inch diameter rotor sure distorts the thin 'wind wall' idea! The funny thing is, in their report they charted better performance setting the blades at 12" diameter than 14".
   Let's see... other graphs show Darrieus peak performance as being at 4 x or 5 x wind speed instead of 6, and all show steep drop offs on either side of "optimum". Is 4 x for three blades and 6 x for two? Then what's 5x for? What to believe? Of course, the width of the blades must be a factor in the best RPM, as well as the number of blades. It's about catching more wind and letting less slip past unused. Certainly more blades sweeps it all at a lower RPM, and the Letcher group only tried a 3 blade design. Presumably 6 blades would cut the best blade speed, and hence the diameter to best match the Savonius, in half? Darrieus rotors of twice the diameter of the Savonius rotors would be more in keeping with the small diameter rotors desired for the wind wall. Too bad the Letcher group didn't try more blades. They said they couldn't find any information on advantages of different numbers of blades. Apparently they didn't consider that they should try to match optimal speeds with the Savonius in their own hybrid rotor. I suspect they would have got better results by adding more. (Although again they got better results with 12" diameter Darrieus than 14", which doesn't seem to fit the theory. OTOH, both diameters should have been way under "optimal". As they didn't mention the diameter of their Savonius, the "ideal" diameter of the Darrieus can't be exactly calculated.)
   But the proportions and with just three blades would seem to indicate a mistake in the design. Either the Savonius is being over-revved by the Darrieus and hence is a drag rather than a contributor, or the Darrieus is being held way under its good producing speed, or both. But perhaps I may be using "conventional" logic that works at higher wind speeds? Their unit is intended to work well in low wind speeds. Also, they got the best results with 4.5 inch blades rather than 3 inch (or 6 inch), so maybe the relatively "fat" blades compensated for the smaller number. All these variables!

   I think I'll try having the Darrieus rotor double the diameter of the Savonius, but with 4 to 6 thinner blades instead of 3 fatter ones. My first Savonius is 7 inches, so the Darrieus should be around 14. (I wonder how far I want to go in trying variations myself without having a wind tunnel for reliable comparisons between them? Hmm... I must remember I do have a good anemometer... and a fan!)

   After getting some performance graphs in a wind tunnel, they looked up typical wind speeds for 4 Ohio cities and compared expected performance against a commercial "Windspire" 20 foot tall Darrieus VAWT. In all cases, at the expected wind speeds over a year, the hybrid design at just 12 feet tall produced substantially more power - from 69% to 177% more. (I'm leaving out one city where they calculated 707% more - apparently owing to very low present production!)

   Finally, not thinking very highly of using stepper motors as generators, I spent 80$ and ordered four small 20W DC generators for 4 columns in the wind wall. (With larger diameter Darrieus rotors, there certainly wouldn't be 6 rotor columns in a meter long 'wind wall', which would also take on more of a 3D aspect with substantial thickness from front to back.)
   But I expect to turn every second hybrid rotor upside-down so the wider Darrieus rotors overlap each other, top, bottom, top, bottom. Thus the width of the wall will be two wider Darrieuses plus two narrower Savoniuses. rather than four wider Darrieuses with gaps between the Savoniuses.

[15th] I tried holding the double Savonius I had made in front of my big square 3-speed fan. At top fan speed it turned lazily around, and sped up a bit. At 20 inches square it wasn't as tall as the rotor, but if the rotors were all to be just half height, about 17 inches, it was big enough. So I had at least one option for testing each rotor under similar low wind conditions.

[16th] "In for a penny, in for a pound..." I went out to the shop (Brr - freezing out!) and made a plywood box with open ends to blow the fan into. That strengthened the air flow and made a mini wind tunnel with fairly "linear" air flow to allow better comparisons of different diameter rotors. I put a hole to mount a bearing at the bottom and another at the top to stick a shaft through. That was convenient and also ensured that every rotor would be in the same place for every test.


   Then I cut my Savonius rotor down to size (2 * 8.5 inches tall) and mounted it in the "wind tunnel". It turned about 60 RPM on high fan, 30 on medium, and came to a stop on low. (At that rate I won't need anything except a clock with seconds to measure RPM!)


   What else was needed? A variable load with watt readings, the anemometer, and and RPM counter. To get an adjustable load I could use a DC to DC universal converter, feed a power resistor through a power monitor, and adjust the voltage or the maximum current limiting of the converter until the rotor was outputting the most watts it was able to (which would be unit watts, if not fractions of a watt), and measure the RPM. Ooops, and a generator. Hum ta tum...
   That way I could try a few different things, and adjust until the Savonius and the Darrieus rotors gave their highest power at the same RPM. (Since they'll be tested separately I would start the Darrieus rotors with a hand spin.)

[17th] I formed pieces of the plastic into the "scoop" shape for the "a little more efficient" Savonius(?) rotor. This time I set the oven to 250°F and got better results - no burning the PVC plastic. I printed out the template from the Letcher document. "Print to fill page" in "Landscape" mode printed it just the right size for the 4 inch pipes, 10 inches end to end. I cut it out and traced it on wood, then cut the four wooden end pieces and screwed the rotors together.
   It was visually, intuitively obvious that although made of virtually the same materials and the same size, the shapes would make them far superior. And if one couldn't form their blades, they were just 1/4 of a round of pipe and a flat piece of about the same width. Nothing in that seems "hard to make".

   In the evening I finished by drilling holes in the wood pieces for a 3/8 inch shaft, and put it together. The free-spinning rotor results were a little better than just lazily, almost barely, turning. It was just more energetic all around. Here is a table of the results:


FAN SPEED
 AIR SPEED
meters/second
(with no rotor
in wind tunnel)
 MAX AIR
SPEED
meters/second
with rotor spinning
 ORIGINAL
"OVERLAPPED
SAVONIUS"
ROTOR RPM
 2nd "FLAT SCOOPS"
ROTOR RPM
LOW
 2.1
 2.1 (8) [5]
 stopped
 40
MEDIUM
 2.6
 3.0 (11) [7]
 ~30
 62
HIGH
 3.1
 3.6 (13) [8]
 ~60
 82

   Air speed was measured at the distance of the rotor axis from the fan. The point of the highest steady speed reading was recorded. A second anemometer gave virtually the same readings as the first. Even the highest speed is pretty slow, as typical windplant cut-in speed is around 4 meters per second. (But it sure felt breezy sitting in front of it - I'd have thought it was more! Maybe because the shop was so cold?) Of course a plant designed for low wind speed will give more power on more days. One designed for high winds will have great output on the few days per year when there are storms.
   With the second rotor air was measured right beside the rotor on the side going upwind, the right side. I thought it was interesting that it was higher than the airspeed with no rotor in the tunnel. On the left side, the speeds were lower.

   RPM was taken after steady speed was attained, by counting turns over 30 seconds and doubling the number. (...counted each time the black cable tie went by the clock.) The outermost diameter of the old rotor was 7 inches, and the new one spun faster in spite of being wider: 10 inches diameter. Doubtless I should have spaced the "air scoops" on the old one father apart with less overlap, but I have no doubt that the new shape "scoops" is better.
   Now I don't understand why anyone ging to the trouble of making a wind plant would make the "two half barrels" shape instead of the newer one. Even if you can't form the "scoops" into the shape you want at will (plastic too big for oven?), they are simply 1/4 to 1/3 of a circle plus a similar area flat section, which could be made in two parts.

   If the Darrieus rotor is to be twice the diameter of the Savonius, that'll be 20 inches. That will certainly tax my 22 inch wide wind tunnel. (And make for a fat "Wind Wall"!)

[18th] The trouble with giving thought to a subject is that thoughts lead to more thoughts, which lead to more things that should be tried out. So far I had been been looking at "flat" shapes, shapes with a one-dimensional cross section that can be made from a single flat sheet of material. And that's all I can remember seeing anywhere for "wind jammer" rotors. The new scoop shape is doubtless better at "scooping" the wind when going downwind, but it does make an area of flat leading surface facing into the wind for part of the rotation, and the most counterproductive part of Savonius operation is the adverse torque of the rotor returning upwind. Here the flat profile must have more drag than the semicircles. But the shape of the leading surface could be different from the trailing surface, giving the rotor cross section a volume. This would be analogous to an airplane wing, which has a different upper surface shape than the underside. This could be accomplished by using two shaped flat sheets, such as adding something like this (thin lines - two variations) to the upwind section:

    Thus it has the "scoop" profile when the wind is pushing it, and a "rounded" profile when it's pushing up through the wind to the front side again. This might even give it better "airplane wing" lift to pull it forward through some parts of the rotation.

   The fact that the profile must be considered through 360° of rotation makes consideration of what the best shape should be - and surely there must be an "optimum" compromise shape - complicated. (It took decades after Savonius before someone even came up with the center gap idea, and still later (1990) the better "scoops" shape instead of "half buckets".)
   Perhaps there's some means for computer modeling at many angles of attack and finding what it might be, but I'm going to have to go with my intuition and sense of proportion. I didn't want to glue a piece of PVC to the original PVC in case I wanted to change it. I wanted something easily reshaped and reattached for at least a few trials. I had some thin aluminum sheets. They could easily be cut and bent, and screwed onto the plastic rotors.

   I did the bottom two and tried it out. The free spinning RPM seemed entirely unchanged.



   Okay, how fast was it turning compared to the wind speed?

Radius is 5 inches or .125 meters. Should sweep the circumference each turn: 2 * π * .125 = .785 meters per turn. Windspeed 3.1 m/s. If the outside of the rotor was going the wind speed, it should turn 2.58 turns per second: 154 RPM. 82 RPM is 1.37 turns per second. So even free-spinning it was only turning half the speed of the wind. Much of this could be bearing friction, but not all. (RPMs seemed to go up as the month went on. Perhaps the spinning shaft was gradually smoothing out the hole in the plywood?)

[19th] The upper section of rotor was more in the center of the tunnel and its airflow. In spite of the disappointing performance so far I decided to try "compositing" the upper one as well. This time there was improvement in no-load RPM, especially with the fan on "High". The decreasingly improved figures on "Medium" and "Low" probably result from increased friction from the increased weight of the rotors. Friction rules much on "low" and "medium" - and doubtless still even on "high". It would have been nice to turn the fan up another notch or two, but it didn't have it.

FAN SPEED
 AIR SPEED
meters/second
(maximum
reading with
no rotor in
wind tunnel)
 1st "OVERLY
OVERLAPPED
SAVONIUS"
ROTOR RPM:
(Second Tests)
(OD = 7")
 2nd "FLAT SCOOPS"
ROTOR RPM
(OD=10")
 3rd
"COMPOSITE"
ROTOR RPM
(OD=10")
LOW
 2.1
 20
 40
 40
MEDIUM
 2.6
 50
 62
 66
HIGH
 3.1
 80
 82
 90

   If a regular "overlapping semicircles" Savonius rotor is 18-20% efficient per some charts and figures, then an improved "scoops" profile rotor is surely at least 20% efficient. The "composite" shape was clearly better than either - perhaps around 25%, then? With this it would seem I have indeed made a better "wind jammer"/Savonius rotor. Well, I don't seem to embark on these sorts of projects without ending up somewhere, in some way, advancing the "state of the art".

BTW First Rotor Retry: I couldn't find the video of the first rotor spinning. Perhaps the camera wasn't actually recording when I thought it was. I reassembled it (ie, with the axle) into the wind tunnel and ran it again for the camera. To my surprise it visibly spun faster than the first time. The friction must have been reduced somewhere in there since the first tests. (I had put in some oil. Also the two piece shaft can be crooked if not screwed together far enough at the coupling nut. That would cause increased friction.) I checked the RPM and put the new figures in the table above. On the first try I read 84 RPM. On subsequent tests it seemed to be around 76. Notwithstanding that it hit about the same RPM as rotor #2 on "High", with a diameter of 7 inches instead of 10 that's lower linear "tip speeds" at the outer rim. And at lower fan speeds it slowed down more than the newer rotors, indicating that as expected it had less torque to overcome friction - or to drive a generator. (At least it turned - barely - on "Low" this time) Power is torque times speed, so it was quite obviously less powerful.
   I could rebuild the first rotor re-setting the "buckets" with less overlap, diameter 8 or 9 inches overall instead of 7. The figures might be interesting and somewhat better, but they obviously wouldn't equal the new design, so I'll probably skip it. The 2nd "scoops" rotors are 10 inches with the same amount of plastic and wood, and the 3rd rotors are the "scoops" with the more streamlined "bucket-ish" front edge added to provide the best advantages of both the others, so they're bound to be better. I'd rather experiment with proportions and placements, if I do, on the ones that are actually proving by comparison that they are better than any existing "Savonius" type rotors.

[20th] More scary thoughts... To progress further along these lines, rotors could be made with moving parts that shift to more optimum orientations depending on what part of the rotation they are in. For instance, what if sections "p" (ref. drawing above) were hinged at the inner end, and could swing back maybe 20 or 30° when going upwind? Air would spill behind toward the "q" area, giving it lowered resistance to moving upwind. But that gets complicated to make, and will probably have a noise penalty when moving parts bang shut. Not to mention they'd probably be a maintenance nightmare.

   Instead, next it seemed more logical to try vanes to get the "venturi" effect to increase the airspeed and better direct it onto the rotors. That would reduce the drag on the rotor returning upwind by deflecting the wind from in front of it - probably an even greater improvement. "Vanes" or "venturis" is disagreeable in principle to many as the rotor no longer will accept wind equally from any direction. But for the "wind wall" it is assumed there is a prevailing wind direction which covers most good winds, or perhaps that the whole wall can be re-oriented (with a steering vane - or simply by hand?) to face the present wind direction. I put a single 7" wide flat plywood vane at about 45° that would deflect the wind normally buffeting the returning side, and aim it toward the power stroke side. It almost touched the rotors with the inner end maybe 2" to the right of center (with rotor going counterclockwise). Anything that pushes more air per second through the rotor on the power stroke greatly improves performance. And for vertical rotors, appropriate deflection also reduces the load against the sections returning upwind. The no-load 160 RPM result seemed more than worthwhile:


FAN SPEED
 AIR SPEED
meters/second
(maximum
reading with
no rotor in
wind tunnel)
 1st "OVERLY
OVERLAPPED
SAVONIUS"
ROTOR no load RPM:
(Second Tests)
(OD = 7")
 2nd "FLAT SCOOPS"
ROTOR no-load RPM
(OD=10")
 3rd
"COMPOSITE PROFILE"
ROTOR
no load RPM
(OD=10")
 3rd ROTOR
WITH WIND DEFLECTOR VANE no-load RPM
(/try 2, 21st)
LOW
 2.1
 20
 40
 40
 80   / 104
MEDIUM
 2.6
 50
 62
 66
 120 / 138
HIGH
 3.1
 80
 82
 90
 160 / 166


    
A "typical windplants(?)" graph on the left shows 15(?)% efficiency at capturing the wind's energy for Savonius
rotors, but the U of Utah paper said it was 18-20% and their own unit (bottom section in picture below) hit 19%.
And it shows best Darrieus speed as 6x wind speed, but in the graph on the right optimum is clearly 4x.
Perhaps this is a difference between 2 and 3 blade models?

   For the first time I could feel a pretty significant pinch on the shaft was needed to slow the little 10" * 19" area rotor pair, so that it would be capable of generating a few watts - maybe even tens of watts - in a low wind. If the #3 composite rotor was capturing 25% of the wind's energy, then with the vane it must surely be 35 to 45%. 40% is the efficiency figure commonly given for a Darrieus rotor.
   A Darrieus rotor with a deflector vane might achieve better than 40%, perhaps even 50%, but at this point I'm thinking I've attained the desired efficiency range with a 'low wind speeds' suitable rotor also more suited to the "wind wall" idea, and that I should drop the Darrieus part of the plan entirely. It is superfluous! And blades turning much faster than the wind speed are bound to be noisy (and more trouble-prone WRT maintenance - and in storms). The whole 'wind wall' idea with the 'slightly under wind speed' rotors will be much more acceptable to potential users. The whole next area of R & D for the project has magicly been eliminated, owing to the unexpectedly effective achievements in the first area!

The Hayes/T. Letcher/Ohio State University, Columbus
hybrid Darrieus/Savonius windplant.

   From what started as a pretty casual project, I engaged in what turned out to be a step-by-step development of a superior "Savonius" type windplant - one that would be actually worth producing to sell for off-grid power. Of course it is scalable to any reasonable size. The humdrum project actually became exciting!

   I tried moving the deflector vane around but only days later found a spot slightly better than its original position, which gave 160 RPM. ("/try 2", on the 21st, above)

   But was there also an optimum shape for the deflector vane? "Flat" works - obviously quite well - but surely "optimum" is something more like the profile of a venturi front opening. And then there's adding a second vane, and vanes on the downwind side. Not tonight! How close to the Betz limit of capturing 58% of the wind's power could one actually come by optimizing this idea?

   What has occurred to me tonight is that one might adopt the idea of having the magnets spinning on a disk(s) at the top or bottom of the rotor, with stationary iron-free coils next to that sending off the electricity. No gears, belts, friction or noise, ultra high generator efficiency.

   Later it occurred to me that the optimum vane shape might be modified as a compromise to better accept wind from, say, 30° to either side of straight on, since even "prevailing" wind direction can vary. The rotors will probably turn with wind from most any direction in spite of vanes, but we do want a range of the most common wind angles where the power is greatly enhanced by them.

[21st] If I added a vane on the downwind side similar to the one upwind, the wall would be bidirectional. The wind could come from either face. Oh, wait... the downwind one would be counterproductive, creating low pressure just where high was needed and vice versa. It should in fact aim the other way. Hmm... So much for "bidirectional"!
   I tried placing a downwind vane in various positions but didn't get more than a very few more RPM out of it - if any. Going back to my calculations of the 18th, it would seem it was already spinning as fast as the wind... but that was the un-accelerated wind speed. But might it have more potential torque, even if the speed wasn't much more?

   With the downwind vanes adding so little, at night I had a new idea. Instead of the "venturi", the vanes should concentrate the wind but also direct it around into a counterclockwise vortex to push the vanes' rotation along as much as possible. Here is the idea as a diagram (clockwise rotor instead of counterclockwise):


   I tried putting in a second vane in various places, which maxed it out at 172-174 RPM but after I tried moving it I never got quite such a good result again.

[22nd] At this point I decided I had something and I decided to write something up for a funding proposal as an "any infrastructure improvement". Along with making the wind wall I proposed to make the rotors out of recycled polypropylene fishnets. I finished it as a "preliminary proposal" the next day, printed it out, and took it in to "Community Futures". I didn't mention money, only that it was a "game changer" for wind power with the most important technical details and some of the same photos and performance charts as here. [25th] I talked to the director, Mike. It appeared they might be more interested in it if it was already in production, or very close to it. (What else is new? Nobody funds the "D" in R & D.)

   Well, what do I really need to get to that point? A means to produce everything. Some of the things are simpler than others. What do I need to produce rotors, wind guide vanes... and perhaps the outer frame parts? I need to melt down PP fishnets in molds to turn them into solid plastic parts.

   Rather than make complex molds with heaters in them, I would rather just make simple molds and heat a whole space with the mold inside it. So first I need a heater big enough to hold any or all the molds. If I make the parts small enough to fit into a kitchen oven, then I just need an oven from the refuse station rather than to create a special heater. And a long cord to the dryer plug inside.
   My own oven is about 2 feet wide. But some pieces of the outer frame will need to be at least 4 feet long or so. Maybe even 5 feet? Probably the simplest thing would be to make a kitchen oven box very deep by ripping the back off and extending it back to 5.5 feet long with sheet steel. I could put extra legs at the back, and wrap it in rock wool insulation. Same oven door, same thermostat and heater element.
   (It also occurs to me that if it'll hold pieces long enough and about 2 feet wide, I could also use it for my other project idea of making transparent greenhouse wall & roof panels from recycled transparent plastic - PP, PS or PETE. That would again be much simpler than my previous idea of making a press mold with heaters built into it!)

   Okay, so an oven for all heating. Then molds for all the frame and rotor parts and pieces? Probably, nearly everything could be made from the recycled PP!
   Starting from the inside with the rotors, two 2-piece alium. molds for the trailing and leading faces are required. I got the 4 foot by 8 foot piece of alium. I've been wanting from Steve, and I can probably have him do any welding they might need. The molds will need some way to press the two faces together. Perhaps some metal "spring clamps", that will continue to squeeze the plastic as it melts until the mold is compressed to the desired thickness? In fact, that sounds about right for all the parts. For these large pieces, melting down un-shredded fishnet for plastic, that's surely simpler than big vats for melting the plastic and pressing it into injection molds?

   I'll try doing rotor molds that will fit in my kitchen oven first, and make sure a few rotors work out well before hauling home an oven, extending it, and making the larger molds for the big pieces.

    All assuming I'm actually going to tackle the project at all. But there's revenue and even "export" (from Haida Gwaii) potential! It's all part of the "off grid infrastructure" overall project.

[Still 25th] I had been shooting video of the various rotors and then the vanes, and late in the evening I made a video and uploaded it to youtube. It might generate some interest, or at least it'll show people some new and improved wind technology.

My video "Evolution of a Windplant": https://youtu.be/S8c06FUBrpg

[29th] Interesting... on a whim I started the fan and checked the RPM of rotor #3 with no vane, and got 104 RPM. then 106. Nothing changed... what happened to 90 RPM?

   I noted that in the "scoops" design the gap at the center is "up-down" while the Savonius is "left-right" with no "up-down" gap. I wondered what would happen if one made the Savonius design but with an "up-down" gap instead? Has anyone ever tried that? If it worked as well as the "scoops", it would also be simpler to make the "from a single sheet" shape.

[Dec 1st] I made this profile (#4) and tried it out. It spun about 102 RPM, just about the same as #3 at 104 RPM. But #3 is 10 inches across, and the new one is only 8.5 inches, so the same RPM represents lower outside edge speed and lower power. The compound faces shape (#3) is better.

The four rotor profiles tried: L - #1, Original Savonius with half-circle edges all ending along a line.
R - New profiles, #2 with plastic scoops only, #3 same with rounded leading faces (metal) added on.
Center - #4, Savonius "half circles" with gap more like #2 & #3. It wasn't as good.

   Have I attained the ultimate "Savonius" type rotor shape? I seems to be better than anything else anyone has come up with. I note that if I insert flat sections inside the #4 "half barrels" it could be shaped very similar to #3 and would surely spin faster. Perhaps like airplane wing and propeller profiles it's the basic best, and so future profiles are likely to be variations of the theme. I'm happy. It's time to move on with development of other aspects of the wind wall and then production.

   As a footnote, I'm not the only one to notice wind directing vanes significantly improves performance. Here is an "omnidirectional" unit with six stationary wind-aiming vanes by Alex Erauw (Youtube - he called them "AVP"), that greatly improved performance of several of his VAWT rotors.
   With the wind wall one or two(?) vanes can be tailored optimally to the prevailing wind direction.


His RPM performance chart. Great wind tunnel!
("AVP" ...something Vortex something...)



My Solar Power System

New Grid Tie Solar Inverters

   Why? I had noticed that the Y-Solar grid tie inverters, while reliable enough, would stop producing whenever the light level quickly dropped by a noticeable amount owing to clouds, and take tens of seconds to ramp up from zero to max again. By then the next cloud would come along. They were okay in a completely clear sky, but we rarely get those here. Far too often I would look at the meters and see and they were be busy ramping up from zero again instead of producing full power. How much energy was I missing out on? Plus I didn't have enough inverters to handle all the solar panels in summer sunlight, so I wanted another one or two more anyway.
   I ordered 3 new 700 watt grid tie inverters, model GM1700/120VAC for 18 to 50 volt DC solar panels.

[30th] These having arrived on the 29th, I swapped out the one on the Cabin system in the morning. I noted that it read about 55 watts before I disconnected the old one, but it took the better part of an hour to hook up the new one. (Wiring mistake - had to redo: +/- swapped - ouch! I don't know if it's protected against reverse polarity or if there just wasn't enough daylight to fry it. Anyway the unit was okay.) After connection to the AC line it waited 3 seconds to ensure the AC was stable and then ramped up in a second or two to 108 watts. Too bad it was too long between readings to compare them. The output stayed pretty steady compared to the Y-Solar inverters, which jump up and down more.
   A month or two of operation should show whether or not there's a notable improvement in overall production.


Power Outage and "Off-Grid" System Improvements

[8th] at around 7PM in high winds and storm, the power went off. It was out (except for a 5 or 10 minute reprieve midday) until 4PM the next day - about 21 hours. I had lots of light in the livingroom with a 12V, .2 or 6 watt COB light I made a while back as well as a 36 volt, 12 by 24 inch ceiling light panel, which I had just made a cord with a 10 ohm resistor for the previous day, with which it drew 13 watts and gave lots of light. (The panels' rating with their AC power adapter is 24 watts. I have now bought 12 the same, specificly because in addition to being fabulous lights, they work nicely at 36 volts DC. A 5 ohm resistor at 39 volts makes it about 20-25 watts.) The computers and internet being off, I did some reading off printed pages - a book, and later reorganized much of the chaos that was my electronics lab by adding a big set of shelves.

   Even by bedtime, the ice cream in the freezer was notably softer. In the morning [9th], not knowing how much longer it would be out, I thought I should start running the fridge and freezer.
   First I unplugged the old yellow set of lithium iron phosphate batteries on the garage floor ("100 amp-hours" but some of the cells are really less), and plugged the house DC into the Sprint car instead (240 amp-hours). Everything is 36 volts. Then I got out a 36VDC to 120VAC inverter and plugged it in to the high current porcelain "T-plug" socket under the kitchen sink, and an extension cord, which I ran to the freezer in the hallway. I ran it for an hour on that, an hour on the kitchen fridge (135W with inverter) and an hour on the garage freezer(also 135W), then pretty much repeated the process, watching that the fridge didn't turn its "430W freezer coil defrost heater" on.
   Once I had this started, I connected the charging also to the car. Then I disconnected one solar panel from a grid tie inverter and added it to the DC system. The charging in the cloudy weather went from 44 watts to 88. Then I tried to add the two panels on the pole, but nothing changed. There was no voltage coming from them. On fixing a bad connection they brought the charging up a little more. But the day was cloudy and the sun low, and only a few times did the charging roughly match the drain from the fridge.
   Only when running my small freezer (80W with the inverter) in the afternoon did the charging start to catch up with the drain from the appliances.

   Once again, this practice run showed serious deficiencies of my system for "off-grid" operation of the house. This time, the biggest one was the solar panels being mostly connected to the grid tie inverters, so they weren't helping to keep the batteries up. I decided to put in DPDT switches so that all the panels could tie into either the grid ties or the DC system, individually or in pairs.
   The second one was that running one appliance at a time and switching them manually won't go very far without being a nuisance and probably often neglected. It doesn't take an unwatched freezer too long to thaw the things stored inside and ruin them. Running at least two items requires two inverters, and three would be better. Three would also require another circuit from the 'solar garage' into the house.

   Another consideration is the total power usage. If an extended outage does occur in the cloudy winter with low sun, the kitchen fridge is the one to 'abandon' first, as it uses the most power, and quite a lot (430W) when doing a defrost cycle. It would be better to use the smaller freezer as a chest refrigerator by turning its temperature control to above freezing, and have one fewer appliances to feed. (I'll need to use up some frozen groceries before doing that!

   It would be good to have another power source besides solar - one that didn't use gasoline. What besides wind? After the power came back on, I got sidetracked by the wind power project and hardly gave another thought to adding switches on the solar panels or any other improvements.


Daily/Monthly/Yearly Log of Solar Power Generated [and grid power consumed]

(All times are in PST: clock 48 minutes ahead of sun, not PDT which is an hour and 48 minutes ahead. (DC) battery system power output readings are reset to zero daily (often just for LED lights, occasionally used with other loads: Electric car, inverters in power outages or other 36V loads), while the grid tied readings are cumulative.)

Solar: House, Trailer, (DC@house)  => total KWH [grid power meter reading(s)@time] Sky conditions
Km = electric car drove distance, then car was charged.

October
31st 2384.71, 1073.69, .09 =>   5.89 [88134@17:30] Sunny with haze at times

November
01st 2386.58, 1074.72, .00 => 2.90 [88170@16:00] not bad
 2nd 2386.96, 1074.89, .14 => 0.69 [50Km; 88225@19:00] Wind & rain, dark.
03rd 2389.42, 1076.20, .00 => 3.77 [88257@17:30] Much nicer.
04th 2389.89, 1076.39, .14 => 0.80 [88291@17:30] Rain again.
05th 2391.23, 1077.03, .14 => 2.12 [85Km; 88342@19:30] Sunny AM with storm, rain & blah.
06th Oops!?!     (1/2 of 2 days) 3.13 [55Km] quite a bit of sun
07th 2395.22, 1079.16, .15 => 3.14 [88420@17:30] Mostly sunny (6.27KWH over 2 days: 3.13 + 3.14)
08th 2395.45, 1079.18, .00 => 0.25 [88469@19:00] Storm - wind, rain, dull.
09th 2395.47, 1079.21, .54 => 0.59 [88477@17:30] Grid power was off. Mostly cloudy. Ran fridge & freezers from DC system with inverters.
10th 2397.43, 1080.62, .41 => 3.78 [55Km; 88516@17:00] Some sun
11th 2397.56, 1080.70, .11 => 0.32 [88572@17:30] Dark and windy
12th 2399.11, 1081.54, .15 => 2.54 [90Km; 88620@18:30] Some sun, some rain.
13th 2399.67, 1081.82, .09 => 0.93 [55Km; 88668@16:30] I've seen nicer days.
14th 2401.78, 1083.00, .11 => 3.40 [88702@16:00] Mostly sunny except for the rain.
15th 2403.53, 1084.04, .10 => 2.89 [88753@17:00] It snew a bit. 0°
16th 2404.23, 1084.69, .10 => 1.45 [55Km; 88801@18:00] 0° ? low
17th 2405.45, 1085.26, .02 => 1.81 [88850@17:30] 9° ? high
18th 2406.37, 1085.83, .58 => 2.07 [88892@17:00; 55Km] "Longest eclipse of the moon in 600 years." (11:19PM to 2:43AM IIRC) The clouds had the decency to part a couple of times so I could see it. Also several telescopes were following it live on youtube.
19th 2407.40, 1086.44, .64 => 2.28 [90Km; 88944@17:00]
20th 2407.63, 1086.58, .17 => 0.54 [90Km; 89001@17:30] Why did the DC system charge up another KWH+? The PowMr charge controller lost its settings somehow and decided it was charging lead-acid batteries to 3 * 14.4 volts = 43.2 volts. If it had got that far, it would have been bad news, maybe even fire or explosion. Luckily it only got to 41V, under the 42V limit. Not to be trusted, these charge controllers! Isn't there any reliable solar charge controller for 36V lithium ion batteries??? I'm disconnecting the solar panels from the charge controller until the voltage is below 40 again.
21st 2407.93, 1086.71, .00 => 0.43 [89048@16:30] Dull, wet. No storm.
22d  2409.69, 1087.47, .00 => 2.52 [89088@16:30] Some sun today. Still no storm.
23rd 2411.02, 1088.08, .00 => 2.37 [55Km; 89131@17:30]
24th 2411.26, 1088.26, .00 => 0.42 [89178@17:00]
25th 2413.50, 1089.40, .00 => 3.38 [55Km; 89219@17:30]
26th 2415.42, 1090.46, .05 => 3.03 [89257@17:00] Running LED lights (& the charge controller) for almost a week, the batteries have finally dropped down in voltage to where the charge controller has put in a bit of juice.
27th 2417.02, 1091.10, .06 => 2.30 [60Km; 89308@17:00]
28th 2418.16, 1091.96, .00 => 2.00 [89355@17:00]
29th 2418.60, 1092.19, .12 => 0.79 [89402@16:30] Ticking away, the hours that make up a dull day.
30th 2419.40, 1092.61, .00 => 1.22 [55Km; 89444@16:30] New grid tie at cabin but missed an hour in AM while installing.

December
01st 2420.53, 1093.20, .09 => 1.81 [55Km; 89489@16:30] Started snowing in evening.
02 d 2421.50, 1093.20, .00 => 0.97 [89542@22:00] More snow. I brushed snow off 2 panels on post & 3 on lawn. Sun for a while. Cord to cabin had come unplugged... when and for how long? no power there! Probably not much under snow covered panels anyway.
03rd 2422.13, 1093.21, .05 => 0.69 [85Km; 89608@24:30] The solar panels at the cabin were still 1/2 covered with snow.

Daily KWH from solar panels. (Compare November 2021 with October 2021 & with November 2020.)
Days of
__ KWH
 November 2021
(14 solar panels)
(2 doing not much!)
 October 2021
(12 solar panels ->
14 by end of month)
 November 2020
(12 solar panels)
0.xx
 10
 1
 8
1.xx
 3
 3
 10
2.xx
 10
 5
 7
3.xx
 7
 5
 3
4.xx
8
 2
5.xx
6
6.xx
3
7.xx


8.xx


9.xx


10.xx


11.xx


12.xx


13.xx


14.xx


15.xx


16.xx


17.xx


18.xx


Total KWH
 57.43
 123.47
 56.49
Km Driven
on Electricity
  917 Km
(~140 KWH?)
 973.6 Km
(150 KWH?)


Monthly Summaries: Solar Generated KWH [& Power used from grid KWH]

2019
March 1-31: 116.19 + ------ + 105.93 = 222.12 KWH - solar [786 KWH used from grid]
April - 1-30: 136.87 + ------ + 121.97 = 258.84 KWH [608 KWH]
May  - 1-31: 156.23 + ------ + 147.47 = 303.70 KWH [543 KWH] (11th solar panel connected on lawn on 26th)
June - 1-30: 146.63 + 15.65 + 115.26 = 277.54 KWH [374 KWH] (36V, 250W Hot Water Heater installed on 7th)
July  - 1-31: 134.06 + 19.06 + 120.86 = 273.98 KWH [342 KWH]
August 1-31:127.47 + 11.44+91.82+(8/10)*96.29 = 307.76 KWH [334 KWH] (12th solar panel connected on lawn Aug. 1)
Sept.- 1-30: 110.72 + 15.30 + 84.91 = 210.93 KWH   [408 KWH] (solar includes 2/10 of 96.29)
Oct.  - 1-31:  55.67 + 13.03 + 51.82 = 120.52 KWH, solar [635 KWH used from grid]
Nov. - 1-30:  36.51 +   6.31 + 26.29 =   69.11 KWH, solar [653 KWH used from grid]
Dec.  - 1-23: 18.98 +   .84* + 11.70 =   31.52 KWH, solar + wind [711 KWH + 414 (while away) = 1125 from grid]

2020
Jan.  - 6-31: 17.52 + ------* + 10.61  =  28.13 KWH, solar+ wind [1111 KWH from grid]
Feb.  - 1-29: 56.83 + ------* + 35.17  =  92.00 KWH, solar + wind [963 KWH from grid]
* The solar DC system was running the kitchen hot water tank. Now it's only running a couple of lights - not (usually) worth reporting. So there's just the 2 grid tie systems: house and "roof over travel trailer".
One year of solar!
March - 1-31: 111.31 +   87.05 = 198.37 KWH solar total  [934 KWH from grid]
April   - 1-30: 156.09 + 115.12 = 271.21 [784 KWH from grid]
May    - 1-31: 181.97 + 131.21 = 313.18 KWH Solar [723 KWH from grid]
June   - 1-30: 164.04 + 119.81 = 283.82 KWH Solar [455 KWH from grid]
July    - 1-31: 190.13 + 110.05 = 300.18 KWH Solar [340 KWH from grid]
August- 1-31: 121.81 + 83.62   = 205.43 KWH Solar [385KWH from Grid]
Sept.  - 1-30: 110.68 + 65.09   = 175.77 KWH Solar [564 KWH used from grid]
Oct.  -   1-31:   67.28 + 42.55   = 109.83 KWH Solar [1360 KWH from grid -- Renters!]
Nov.  -  1-30:   35.70  + 20.79  = 56.49 KWH of Solar [1301 KWH from grid]
Dec.  -  1-31:   19.78  + 11.31  = 31.09 KWH Solar [1078 KWH used from grid]

2021
Jan.   -  1-31:   25.47 + 18.58  = 44.05 KWH Solar [1185 KWH used from grid]
Feb.   -  1-28:   47.18 + 33.22  = 80.40 KWH Solar [1121 KWH used from grid]
Two years of solar!
March - 1-31:   81.73 +  55.22 + 2.2 (DC) = 139.15 KWH Solar [1039 KWH grid]
April  -  1-30: 161.83 + 112.35 + .44(DC)  = 274.62 KWH Solar [680 KWH from grid]
May   -  1-31: 156.25 +  97.22 + 1.29(DC) = 254.76 KWH Solar [678 KWH from grid]
June  -  1-30: 197.84 + 112.07 + 2.21(DC) = 312.12 KWH Solar [& 448 KWH from grid]
July   -  1-31: 204.35 + 121.21 + 4.06(DC) = 329.62 KWH Solar [426 KWH from grid; 150(?) KWH used by Nissan Leaf]
August- 1-31: 176.19 + 102.91 + 5.37(DC) = 284.47 KWH Solar [477 KWH from grid; 165 KWH (est) used by car]
Sept. -  1-30:   94.35 +   51.34 + 3.30(DC) = 152.29 KWH Solar [590 KWH from grid; 155 KWH (est) used by car]
Oct.   -  1-31:   77.52 +   41.85 + 4.10(DC) = 123.47 KWH Solar [1066 KWH from grid; 150 KWH (est) used by car]
Nov.  -   1-31:  34.69 +  18.92 + 3.82 = 57.43 KWH Solar [1474 KWH from grid (ouch!); 140 (est) used by car]

Things Noted - November 2021

* Toward the end of the month tree shadows even from across the highway and from the acreage to the south were seriously interfering with solar collection. It's another reason there isn't much solar in the winter.

* I don't drive every day but when I do it's generally a 55 or 85 Km trip. Looking at the power usage, the car isn't a very big part of the total load. In winter electric heat is most of it. The solar production accounts for substantially more than the car uses, and the solar equipment cost a lot less than the car did.


Annual

March 2019-Feb. 2020: 2196.15 KWH Solar [used   7927 KWH from grid]
March 2020-Feb. 2021: 2069.82 KWH Solar [used 11294 KWH from grid]

(See TE News #156 for the two year writeup... which technicly should have been two months earlier.)

https://www.TurquoiseEnergy.com
https://TurquoiseEnergy.neocities.com
Haida Gwaii, BC Canada