harrisonpatm
Member
- Joined
- Jan 5, 2022
- Messages
- 392
I got on the forum for all of it's awesome resources having to do with using secondhand lithium cells, and I know that nearly all of the readers are solar users. Solar is great. And yet, building wind generation just had such an appeal to me for the last few months. I've learned enough (still so much more to learn) to know that at some point in the next couple of years, I'm sure I'll be breaking down and finding some secondhand solar panels to stick on my house and get some use out of these thousands of 18650's you folks are helping me process. In the meantime... behold the jankiest homemade wind power setup you've ever seen!
Goals for the project were to spend as little money as possible and do as much construction from scratch as I could. While the ultimate goal of having a few wind turbines down the road, with enough output to fully supply power to my house, would be awesome, it's less than likely. Main goal was to learn, secondary goal was to have a small setup to charge my phone, kid's toys, tablet, small devices, some lighting, ect. There are also local restrictions in place in my area from installing anything significant (including solar). And I'm not quite there yet! But I have made a lot of self-taught progress and I would love some feedback and suggestions as I move forward.
Turbine #1
This is a 5-bladed Lenz style turbine using a modified hoverboard wheel as an alternator. A scrap bicycle wheel is mounted centered on top of the alternator, with the 5 "blades" mounted evenly on the rim. Blades are made of 4in PVC, halved, mounted askew using aluminum L-angle, and flushed out with scrap house siding to catch the wind on the drag side. Galvanized wire on top to keep them from wobbling. At 20mph winds, I get about 80-120 rpm. Benefits is that I don't need a yaw mechanism, it catches the wind from any direction. There's also a relatively significant amount of weight from the vanes on the exterior of the wheel, which gives it a nice flywheel effect. It's efficient at catching even small breezes, and once it gets going, the flywheel keeps it moving. Great torque. Downsides are that vertical axis turbines are not as efficient at catching windpower, and despite having great torque, it never gets terribly fast even in high winds, so therefore low voltage. On my to do list is to remount it totally differently; I want the turbine's spin to gear up to the alternator, instead of direct drive, then I should be able to get more voltage. Even 1:2 or 1:3 would be awesome.
Turbine #2. This one is still in prototype testing stage, lots of improvements, but it's generating as is, so I'm including it
Another hoverboard wheel (so cheap and easy to find, if not free), this time a more traditional horizontal axis. Blades are once again PVC, this time 1/3 lengths, shaped to give a leading and trailing edge. The mounting plate and bearing is repurposed from an old industrial fan that I found. Yaw mechanism is a thrust needle bearing, no slip ring yet, cuz I'm still just testing. Which is also why it's not mounted higher up yet. The tail, as I've learned, also needs to be bigger, and on a longer boom. So most of it's time it's not actually facing wind, I either move it myself or the wind is strong enough to push it around, until I get around to remaking the tail fin and boom. But oh boy, when it does get going, it barely needs any wind at all to get ripping. This is in 12-15mph winds:
It's no wonder why 90% of all the giant 300ft wind turbines all look the same. It's a very effective design, even on a small scale with little precision.
And now for some good laughs: in moderate 12-20mph winds, turbine #1 ouputs about .5-1amp at 3-6 volts. Turbine #2, 1-1.5amps at 8-12 volts. Barely anything! Wohoo! So what's the point, amiright?
Point is it was all junk, scrap, used parts, spare time, and a ton of learning experience. I've spent less than $200 on everything all together, including the electronics introduced next, and I'm getting a little bit of usable power out of it. The learning can easily be applied to larger control systems that I can purchase later with solar or higher-output turbines. Plus, I'm simultaneously collecting, processing, testing used 18650's, on which I'm spending exactly $0, for an eventual home powerwall. These projects are giving me something to do with my substandard cells, and I'm practicing using them, so I can learn from my current mistakes before I build the big powerwall.
Onto the charge control and storage. Since I'm only getting like 5-15 watts at a time, no Amazon or Ebay charge controller is able to stoop that low to actually get me to store any of this energy. I have to build it myself using off the shelf components, doing things with them they are very much not designed to do. Since I don't have a lot of electronics experience, this has been very fun learning experience, and the setup is always changing when I want to try new ideas. If you like nice tidy organized wires, please scroll down and skip the next picture.
Battery is a 1S24P made of my mediocre cells, 1800-2000mAh. All in parallel, I get about 45-48 usable amp hours. Since I'm just using this for charging 5V devices for now, this a relatively huge bank. This is so that if I have multiple non-windy days in a row, the battery is never actually in much danger of draining dry. I have a small voltmeter connected to it for SOC, which I can turn on/off with a switch so that it's not a parasitic drain. It doesn't have it's own BMS, persay, but the output is done through a TP4056 (introduced below), and I don't have any series connections to worry about getting out of balance. Plus I'm playing with the setup and monitoring it constantly every day, so I'm not worried about it getting under- or over-voltage.
The "charge controller" is on the small wooden board on the right side of the picture. Since turbine #1 never gets high voltage, what I've done is rectified the 3-phase output and connected that to a small boost converter, MT3608, calibrated to 5.0V output. When the turbine spins up to about 1.7V, this provides enough input voltage to boost to 5V. The 5V output goes to a TP4056, which goes to the battery and charges it with whatever scavenged milliamps it was able to get from the wind, The TP is rated for 1 amp, and I can guarantee the turbine rarely actually gives it that much. For output, on the same "circuitboard," I have a cheap USB boost module taking the battery voltage and boosting it to 5V to charge phones, devices, ect. I have a 2A dual USB charging module on order, and when it arrives, I can put everything in a decent box to tidy up the wiry mess.
Turbine #2 was much easier to get power into my 1S pack, it spins a lot faster in relatively low winds and easily gets up to 8-10V. Yet still not high enough for even the cheapest Amazon wind charge controller to handle, which usually require 12-24v and would be a $30 waste of money. Instead, I've connected the rectified output to a buck module, a cheap 5A board for $1.52, and set the output to 4.18V. I've tested this in a controlled setting with a power supply to charge 18650's normally, and can confirm that as long as it's set correctly, there's never a chance of battery overvoltage. So what happens is that turbine #2 spins up, and once it gets above the battery's current voltage, any current generated goes into the battery, regulated to 4.18V. 8, 10, 12V coming out of the turbine, only 4.18V into the battery. High turbine voltage is essentially getting turned into higher amps to maintain 4.18V (or at least that's as much as I've been able to learn. Someone please correct me if I'm worng!) The buck converter is rated for about 30V input, and this current turbine stays way under that. I can also limit current with this board, and have set it to 2A, but again, I never get that high.
Exact power generation, in watt hours, is hard to calculate, mostly because cheap power meters have a minimum input of 6V, but at the same time, I don't particularly care. I get red LED's when charging is occuring, I charge mine and my wife's phone and my kids' toys every day, and the battery gets replenished 24hrs a day, sporadically. It moves between 3.5 and 4V. So the system is working. It's horribly inefficient, and a mess, and a constant project, but it's also fun and incredibly educational, and all my materiels, excluding cheap electronics, are used, scrap, secondhand or junk, extremely low cost. I also know that this method of charging is essentially trickle charging, and not particularly good for the health of the battery, but it's my low quality salvaged secondhand cells that were about to be thrown away by a computer repair shop anyway, so that also doesn't really matter in this situation. I'm saving the good cells for bigger projects.
So that's about it for now. I would love some feedback. It's a totally unique project, so it's been quite hard to find suggestions on the internet, because who in their right mind would spend this much time and effort on something that only gives you a few watts? This is going to be a constant work in progress. I have 2 more turbines planned. I'm always changing my mind or trying out a new setup with the charge controller or the blades or the placement in my yard. And solar is definitely a couple years down the line.
Thanks for reading!
Goals for the project were to spend as little money as possible and do as much construction from scratch as I could. While the ultimate goal of having a few wind turbines down the road, with enough output to fully supply power to my house, would be awesome, it's less than likely. Main goal was to learn, secondary goal was to have a small setup to charge my phone, kid's toys, tablet, small devices, some lighting, ect. There are also local restrictions in place in my area from installing anything significant (including solar). And I'm not quite there yet! But I have made a lot of self-taught progress and I would love some feedback and suggestions as I move forward.
Turbine #1
This is a 5-bladed Lenz style turbine using a modified hoverboard wheel as an alternator. A scrap bicycle wheel is mounted centered on top of the alternator, with the 5 "blades" mounted evenly on the rim. Blades are made of 4in PVC, halved, mounted askew using aluminum L-angle, and flushed out with scrap house siding to catch the wind on the drag side. Galvanized wire on top to keep them from wobbling. At 20mph winds, I get about 80-120 rpm. Benefits is that I don't need a yaw mechanism, it catches the wind from any direction. There's also a relatively significant amount of weight from the vanes on the exterior of the wheel, which gives it a nice flywheel effect. It's efficient at catching even small breezes, and once it gets going, the flywheel keeps it moving. Great torque. Downsides are that vertical axis turbines are not as efficient at catching windpower, and despite having great torque, it never gets terribly fast even in high winds, so therefore low voltage. On my to do list is to remount it totally differently; I want the turbine's spin to gear up to the alternator, instead of direct drive, then I should be able to get more voltage. Even 1:2 or 1:3 would be awesome.
Turbine #2. This one is still in prototype testing stage, lots of improvements, but it's generating as is, so I'm including it
Another hoverboard wheel (so cheap and easy to find, if not free), this time a more traditional horizontal axis. Blades are once again PVC, this time 1/3 lengths, shaped to give a leading and trailing edge. The mounting plate and bearing is repurposed from an old industrial fan that I found. Yaw mechanism is a thrust needle bearing, no slip ring yet, cuz I'm still just testing. Which is also why it's not mounted higher up yet. The tail, as I've learned, also needs to be bigger, and on a longer boom. So most of it's time it's not actually facing wind, I either move it myself or the wind is strong enough to push it around, until I get around to remaking the tail fin and boom. But oh boy, when it does get going, it barely needs any wind at all to get ripping. This is in 12-15mph winds:
It's no wonder why 90% of all the giant 300ft wind turbines all look the same. It's a very effective design, even on a small scale with little precision.
And now for some good laughs: in moderate 12-20mph winds, turbine #1 ouputs about .5-1amp at 3-6 volts. Turbine #2, 1-1.5amps at 8-12 volts. Barely anything! Wohoo! So what's the point, amiright?
Point is it was all junk, scrap, used parts, spare time, and a ton of learning experience. I've spent less than $200 on everything all together, including the electronics introduced next, and I'm getting a little bit of usable power out of it. The learning can easily be applied to larger control systems that I can purchase later with solar or higher-output turbines. Plus, I'm simultaneously collecting, processing, testing used 18650's, on which I'm spending exactly $0, for an eventual home powerwall. These projects are giving me something to do with my substandard cells, and I'm practicing using them, so I can learn from my current mistakes before I build the big powerwall.
Onto the charge control and storage. Since I'm only getting like 5-15 watts at a time, no Amazon or Ebay charge controller is able to stoop that low to actually get me to store any of this energy. I have to build it myself using off the shelf components, doing things with them they are very much not designed to do. Since I don't have a lot of electronics experience, this has been very fun learning experience, and the setup is always changing when I want to try new ideas. If you like nice tidy organized wires, please scroll down and skip the next picture.
Battery is a 1S24P made of my mediocre cells, 1800-2000mAh. All in parallel, I get about 45-48 usable amp hours. Since I'm just using this for charging 5V devices for now, this a relatively huge bank. This is so that if I have multiple non-windy days in a row, the battery is never actually in much danger of draining dry. I have a small voltmeter connected to it for SOC, which I can turn on/off with a switch so that it's not a parasitic drain. It doesn't have it's own BMS, persay, but the output is done through a TP4056 (introduced below), and I don't have any series connections to worry about getting out of balance. Plus I'm playing with the setup and monitoring it constantly every day, so I'm not worried about it getting under- or over-voltage.
The "charge controller" is on the small wooden board on the right side of the picture. Since turbine #1 never gets high voltage, what I've done is rectified the 3-phase output and connected that to a small boost converter, MT3608, calibrated to 5.0V output. When the turbine spins up to about 1.7V, this provides enough input voltage to boost to 5V. The 5V output goes to a TP4056, which goes to the battery and charges it with whatever scavenged milliamps it was able to get from the wind, The TP is rated for 1 amp, and I can guarantee the turbine rarely actually gives it that much. For output, on the same "circuitboard," I have a cheap USB boost module taking the battery voltage and boosting it to 5V to charge phones, devices, ect. I have a 2A dual USB charging module on order, and when it arrives, I can put everything in a decent box to tidy up the wiry mess.
Turbine #2 was much easier to get power into my 1S pack, it spins a lot faster in relatively low winds and easily gets up to 8-10V. Yet still not high enough for even the cheapest Amazon wind charge controller to handle, which usually require 12-24v and would be a $30 waste of money. Instead, I've connected the rectified output to a buck module, a cheap 5A board for $1.52, and set the output to 4.18V. I've tested this in a controlled setting with a power supply to charge 18650's normally, and can confirm that as long as it's set correctly, there's never a chance of battery overvoltage. So what happens is that turbine #2 spins up, and once it gets above the battery's current voltage, any current generated goes into the battery, regulated to 4.18V. 8, 10, 12V coming out of the turbine, only 4.18V into the battery. High turbine voltage is essentially getting turned into higher amps to maintain 4.18V (or at least that's as much as I've been able to learn. Someone please correct me if I'm worng!) The buck converter is rated for about 30V input, and this current turbine stays way under that. I can also limit current with this board, and have set it to 2A, but again, I never get that high.
Exact power generation, in watt hours, is hard to calculate, mostly because cheap power meters have a minimum input of 6V, but at the same time, I don't particularly care. I get red LED's when charging is occuring, I charge mine and my wife's phone and my kids' toys every day, and the battery gets replenished 24hrs a day, sporadically. It moves between 3.5 and 4V. So the system is working. It's horribly inefficient, and a mess, and a constant project, but it's also fun and incredibly educational, and all my materiels, excluding cheap electronics, are used, scrap, secondhand or junk, extremely low cost. I also know that this method of charging is essentially trickle charging, and not particularly good for the health of the battery, but it's my low quality salvaged secondhand cells that were about to be thrown away by a computer repair shop anyway, so that also doesn't really matter in this situation. I'm saving the good cells for bigger projects.
So that's about it for now. I would love some feedback. It's a totally unique project, so it's been quite hard to find suggestions on the internet, because who in their right mind would spend this much time and effort on something that only gives you a few watts? This is going to be a constant work in progress. I have 2 more turbines planned. I'm always changing my mind or trying out a new setup with the charge controller or the blades or the placement in my yard. And solar is definitely a couple years down the line.
Thanks for reading!