Solar Tracker Idea

[ruddycrazy]

G'day Guy's,
                   Well with the drive to jobs taking an hour or more I've plenty of time to think about making a PV tracker for the extra 5Kw I'm going to put onto our array. Rather than just plonk them onto the roof and get the best output once a year I do think a tracker is the go.

                  Now as we know the sun moves a set path each day and seasonal adjustments will need to be made, so my idea is have a rotating system for the normal time base then a system to track the azimuth so the tracking array can be self sufficient.

                  I do have to wait until the 22nd of this month to get a legal copy of autocad due to download restrictions so after that I'll do some cad drawing to show what I mean by my tracker design.

                So what do you guys think is this worth a go......

Regards Bryan 

[jack11]

I'v welded up 1-axis frames that I rotate by hand east-to-west throughout the day, and lock them in 3 different positions, to track the sun in azimuth.

To track in elevation, I simply tilt these frames toward the south in the winter (I am in the US), and lock them in one of 3 positions throughout the year.

This was worth a go for me, the system produces much better than flat-mounted panels.

Going fully automatic however, with az-el motors, is much more difficult and expensive to implement (even though the concept is simple), I don't know if I'll ever do it.

[madlabs]

I love the idea of trackers and have wanted to build one. I have the tools to do it and would really enjoy building and programming the controller. I even have a motor from a huge dish antenna.

But I just can't justify it as a project. It is so much easier and cheaper to throw up a few more panels to make up the difference. And it helps most in summer, when I have plenty of power anyway. The only time I think I would do it would be if space was so limited that I couldn't fit enough panels.

Jonathan

[frackers]

According to http://www.macslab.com/optsolar.html then you'll need a 2 axis tracker to make any real difference. I'll be changing the angle of mine twice a year to increase the yield from 70% to 75%. I've drilled the holes for the "can't be bothered to get on the roof and change then all" position but we'll see how the double change works for a couple of years first.

[madlabs]

I did the same with my first array and managed to keep changing it for almost two years. Then I just left it in the spring/fall setting. When I built my new array I didn't want to go to the extra engineering and building trouble, so I just made it fixed.

But then, I'm a lazy bugger...

Jonathan

[rossw]

you'll need a 2 axis tracker to make any real difference.

As someone who's designed, built and operated 6 arrays for quite a few years, and left two identical arrays of identical modules on non-tracking frames as a comparison, and installed a pyranometer to measure actual operational efficiency day in, day out, year after year... I can only say that the above statement is utter BS.

[mab]

I must admit that now solar is so cheap (compared with when I built my 1st tracker) I'm thinking madlabs is right in that you can just have additional arrays angles east & west.

But if you've got a limited amount of solar or space then an east-west  tracker can help a lot.  Where I used to live, it's not unusual for the day to start sunny, but then the clouds build during the middle of the day, then clear up again in late afternoon, and when I made the panels tracking, I got more power into the battery by mid-morning than I got in a whole day with the panels fixed south.

I haven't triedautomated up/down tracking, just moved them manually, seasonally, and in practice I no longer put them in the steep winter position as in winter there's more to be gained by having them facing up to make the most of the overcast than trying to optimize for the occasional sunny day.

[clockmanFRA]

Hiya,

Did a design last year and talked about it on here, somewhere?

I am too old to make it a business venture so I will be putting the 1.5kw and the 2kw new design in a small A4 booklet and let folk have it for the printing costs.
Catchy title, “How to make a cost effective, 1.5kw & 2kw, double axis PV Solar Tracker”

Mine have had good blows of wind and storms, snow, rain and cats, sheep, and they are still going strong.

On the European Forum:-  http://www.navitron.org.uk/forum/index.php/topic,20386.0.html

We here, not for Profit, http://www.echorenovate.com   have done some initial data tests and our trackers are getting a good 25% more that a fixed array, Mrs reckons nearly 30%, but I am happy with 25% more power.

[southpaw]

Have to agree with rossw on this one. The report by macslab is very misleading as they compare 2 axis tracking to manual tilt, but don't compare it to east/west tracking or e/w tracking with manual tilt.
This just goes to show that given a bunch of numbers and the right motivation you can make a case for just about anything, sounds like advertising. Don't believe anything you read or hear and only half of what you see.

[slmauk]

I wanted to share a little project that I did at my home. I had recently installed a small,(200 watt) set of panels, and wanted to be able to squeeze all I could out of them. On top of a tower section I mounted a 16" steel disk that I had bored a hole through and installed a bushing in, as well as two grease fittings. Then I took a second steel disk and welded a shaft through the center so one plate would sit on top of the other. On the top plate I mounted the frame that held the panels. $20.00 at a flea market and I had an antenna rotor and control box. Simple enough to mount the motor, but I wanted it automatic. When I opened the control box I found 2 sets of switches that were operated by a small, motor-driven cam. One set was a N.O. contact. This has to close for the rotor to run. The second switch was a three-wire, form-C type contact with a common and the other leads N.O. . The second switch selects the direction of rotation. I had a very small Eaton brand of PLC that I had pulled from a junked out pump system. I wrote a simple program for it that sends the proper signal to the proper leads and so far it has been working great. The PLC has accurate timers and the rotor motor is stepper type.  If a person couldn't get hold of a PLC, they could build the same system with industrial timers. If your interested, want to see a pic of something, or have a question or suggestion, let me know.     Thank you very much.
   P.S. Those two steel disks were supposed to be going into an axial flux wind generator, so I guess that project is delaed for now.

[dnix71]

Panel output drops off quite a bit in hot weather. A non-reflective top coat and passive heat sinking might get you better performance without the fancy gear motors and electronics.

[WindriderNM]

I have a tracker that has a shaded cylinder on each side that are partially filled with propane with a 1/4 inch copper tube connecting them at the bottom. As they get out of alignment the sun shines on the lower tube vaporizing some of the propane and forcing the liquid into the upper tube making it heavier this brings the array back into alignment. It has a couple of shock absorbers to dampen the movement and a counterbalance weight. I got this from an auction. I have seen several of these in operation they seem to work well and have very few moving parts. They are made by Zomeworks in Albuquerque New Mexico. It would be easy to make one. Mine came with 16 panels is approximately 8 feet wide by 16 feet tall and has a pivot for manual seasonal adjustment. It wouldn't be hard to put a gearhead motor with a drum attached to it and some cable or seasonal adjustment either with a switch or some type of automatic control.

[Bruce S]

I have a tracker that has a shaded cylinder on each side that are partially filled with propane with a 1/4 inch copper tube connecting them at the bottom. As they get out of alignment the sun shines on the lower tube vaporizing some of the propane and forcing the liquid into the upper tube making it heavier this brings the array back into alignment. It has a couple of shock absorbers to dampen the movement and a counterbalance weight. I got this from an auction. I have seen several of these in operation they seem to work well and have very few moving parts. They are made by Zomeworks in Albuquerque New Mexico. It would be easy to make one. Mine came with 16 panels is approximately 8 feet wide by 16 feet tall and has a pivot for manual seasonal adjustment. It wouldn't be hard to put a gearhead motor with a drum attached to it and some cable or seasonal adjustment either with a switch or some type of automatic control.

That's interesting. I remember Mother Earth News and others trying this approach without much success. Would it be possible for you to post a pic of the setup?

[Flux]

With a carefully balanced system, what stops the wind blowing it back and forth against the stops, quite a lot of wind area there?

Flux

[XeonPony]

if I recall correctly compressed gas shocks.

[Mary B]

The gain from rotating can't overcome my peace of mind having fixed panels when I get 90mph winds.

[WindriderNM]

I have seen several of these trackers in use the wind doesn't seem to be a problem. Mine came out it on a flatbed trailer it hasn't had any problems with wind up to 60 miles an hour. I have a friend who has one that has seen 80 mile an hour winds without a problem. I have seen them all different sizes I have seen one that only held two panels about 50 W each. Zomeworks has been making these for several years my is over 20 years old and I just saw a new one at a electrical installation store in Alamogordo New Mexico. I won't be to the house where mine is at for a few weeks but will photograph it when I'm there. If you go to  Zomeworks.com there is a lot more information about them in a detailed description of how they work.

[WindriderNM]

After posting the previous post I looked at the Zomeworks.com  website and saw a system where the solar panels are mounted on cables, they have a passive or active tracking system. This looks like it might be an inexpensive way to mount panels either tracking or fixed.

[eco007]

I also love the idea of solar tracking. I also looking any tools or software so that we can tract it 

[thirteen]

I live where the temp goes down to -20 -30 for 30-45 days I would like a tracker for my solar panels but the low winter temp puts a damper on a tracker. Plus I am 500 ft from any power source. Any good ideas for a cold weather tracker. 4000 ft elevation

[azjustin]

Something like this?  According to Zomeworks, this was the prototype built in Tucson, AZ that proved the design they still use now.  They installed it in '87 IIRC, and it worked every day until I brought it to my place in 2011.  Haven't got it back up yet since engineers want a years salary to design the hold downs, but soon it will be up soon since I  passed all my inspections for grid tie.

Two cables hold the panels, the gas shocks (2) keep the wind from ripping it apart in addition to intermediate support, and the passive collectors rotate the panels.

[Bruce S]

NICE! I look forward to seeing this setup back up and working.

[Mary B]

I could see the wind here shredding that in a month... just had 65mph 2 days ago.

[Frank S]

I would have to say  the mounting and anchorage of that system would depend a lot on the direction of the prevailing winds in the high desert of West Texas I could see that system going the route of galloping Girdie
 However simple winglet like deflectors  positioned and located in the right places could serve well enough to prevent destructive harmonic resonance build up.

[XeonPony]

here's mine. just need some more steel and some gearing for the asmiuth drive.

[Mary B]

If you can locate an old solid fiberglass 10 foot satellite dish it will give you the parts you need for a polar tracking mount.

[WindriderNM]

Homecare hospital beds also have the actuators to make a tracker.

[clockmanFRA]

Further to my post earlier in this Topic.

My New 2kw design is up and running.

These individual Yingli 250w PV Panels are supposed to be top quality, but did not cost me that much.

Interestingly these New Mono 250w panels each have nearly a 40v output, so 4 in each string give me about 160v into the controller, Tristar's just will not handle that.

So 7 Tristar controllers later, (I also have 3off 12 footer Wind Turbines and a static 2kw PV) I have installed a Midnite Classic 200.  see, http://midniteforum.com/index.php?
PHPSESSID=1ero2n9a6u43t4oa89uc4vkl84&topic=1475.0

The MPPT controllers are still managing just over 500w of input to my 48v batteries, even on a dull and raining day.

Note, I have also just started installing another 2kw of wall/ground static mounted PV 250w panels, So I can give REAL actual DATA on Static verses Tracker.

[DamonHD]

Yes, I shall be interested on static vs tracker in mid-winter when extra output would be most useful...

Rgds

Damon

[Bruce S]

I'm liking the organic base guardians  .
My area has room for a tracker, but just barely, so I too will be once again interested in tracker versus static base(s).
Cheers;
Bruce S

[clockmanFRA]

Organic base Guardians,  well I have heard sheep being called all sorts of names, but that is a new one on me. lol.

Our ladies, are the French 'Rouge de West', the ram that's here for a month is a good old English 'Suffolk'.

I will keep you posted on Real Data regards the 2kw Static against the 2Kw Tracker. Both new controllers went in at about the same time.

Pleased that the Mono PV Panels are still giving me 10% of their rated output in ambient light conditions.