Again as others have said, excellent work and excellent documented results. I have a several of comments: 1) You should view another TH-cam experimenter who demonstrated a "genius setup" tractor of two large solar panels balanced via a hinge on a see-saw horse whose panel tracking is automatically done ONLY by an additional small pair of steering solar panels powering a $20 motorized actuator arm. No sophisticated computer serup! It's an extremely simple setup. The key is to reverse the power leads from the small steering panels so to supply voltage in an additive/subtractive method to the actuator arm's stepper motor, by changing voltage director to the DC motor, as the Sun moves across the sky. Thus advancing or reversing the tractor's DC motor direction and the large solar panels position. 2) In your "fixed solar panel" experiment test you placed it totally horizontal, flat eg 0° degrees. Whereas, in actual fixed solar installations installers set the fixed panel say at 32° deg angle to face the region of the sky where the maximum Sun tracks across the sky at higher intensity say 10 AM to 3 PM. Perhaps if you had placed your fixed panel in a similar angle Sun facing way, it seems to me you would capture more solar power for the day. Perhaps enough, where the power differences between fixed vs tracking would be smaller. (Maybe next time.) 3) My thought considering how complex and expensive Sun tracker systems can be to gain a 25% to 30% improvement, wouldn't it be simpler and more cost & power effective for home setups just to add an additional fixed non-tracking solar panel. 4) Again, you produced EXCELLENT data comparison results of a single tracker vs a fixed horizontal panel. You Go Girl!! - Paul
Jessica, that's a real interesting and very clear study here. Thanks. For those who are talking about adding extra panels. The tracking system allows 25% on top of the constant high voltage production throughout the day. Which won't do these extra panels.
Great presentation! Thank you. When there is not room for more panels this is the way to go. Solar farms in the Northern US are using single-axis trackers.
Good stuff. Theoretically on a dual axis you would get 5-10% more as the sun moves over it move sideways or vertically for us planet side. Theoretically the maximum is + 39.7%.
To give a little context, the ballpark figure that most people throw around for tracking systems is up to 30% improvement in harvest, so your results are pretty much in the ballpark.
Great video. Nicely done. I do wonder if there would be a way to hook it a computer and record trends over time and compare that to weather conditions from a home weather station, use a photo resistor to record the suns intensity etc.
Hi Jessica. I have the Eco Worthy dual axis tracker. I have 2 arrays. All panels are identical; Trina 400w. 1st: 2 panels laying on the ground, tilted about 12" and facing West. 2nd: 1 400w panel on the tracker. It has been averaging just over 1 KWh a day.. 1.8KWh\312w, 1.16\320w, 1.12\317 for the past 3 days. Late yesterday after the sunset, I added a 2nd 400w panel to the tracker. It's now getting 1.24KWh. The 1st array is getting 890Wh and just 417w. So YES.. trackers work.. I have 6 new bi-facial 200w panels arriving on Friday (1200w) which I will mount on the tracker. Overall these 2 arrays make about 2KWh a day.. but that will go up drastically soon. I have a Victron 150\100 for the 2-400s and a Victron 150-45 for the 2nd one. I have a video on my channel of it. You should do this same test with a dual axis tracker. I'm certain the numbers would be more..
Excellent Professional Video, content was sufficient, informative, and detailed. The actual data results speak for themselves. Now how about grabbing the data remotely via WiFi 2.4ghz on just the tracker and piping it back real time (every 3-5 minutes) to your Home router so You can monitor and track it on a Raspberry Pi attached to your home network? Great job, you will go far at this pace!
Usualy non-tracking sistems installing not in fully horizontal position, but with about 30 degrees to horizontal surface. I think in this case improvement will be less then 25%
Nice field test. Can you repeat: 1. using a MPPT Charge controller 2. placing the non-tracking solar panel at the angle for maximum solar yield (i.e. latitude) 3. apply a constant load to the setup Lovely experiment
Thanks for making the comparison(s) This is really important when solar pumping …but not a game changer if charging batteries. Best to over size system by 150 to 200% capacity for cloudy conditions and or mount extra panels to cover the full sun’s arc.
Great experiment! Considering how sharp power data changes in the early and late hours of the day where tracking makes a huge difference, I would only guess that the improvement percentage would be better for a higher resolution data/measurement.
Thank you very much Jessica! Congratulations for your experiment! Only one thing I didn't understand: when it's cloudy, the generation is really zero? Thank you!
Thank you and yes that's correct! This solar panel is pretty cheap and small so on the days where it was really cloudy, it was unable to generate any power.
I would be very interested to see how a 2-axis tracking compares to the fixed 1-axis system that you show here. What formula or equation did you use the determine the area under the under the watts line on your chart? I presume you used a spreadsheet (Excel?). The problem with trackers is a). the additional cost & maintenance &, b). the potential for damage due to strong winds. I live in the UK & we have short periods of ferocious gale force winds that would tear apart most tracking PV systems. Could you detail the exact components you used (manufacturer, reference number & specification) & their costs please. I up-ticked your video; well done Jessica. Regards, JohnnyK.
Hi, John! I hope this helps! I think explaining by text might be a little confusing and long, so I'll just link the spreadsheet I made for all my data collection here for you to see: docs.google.com/spreadsheets/d/1mXE6vnOvNZ5RhREiE107h2ph80cnrbCfERHAFbYU-xw/edit?usp=sharing I totally agree that trackers have their downsides. Fortunately, I live somewhere with pretty weak wind and I use this solar panel setup every once and a while for fun so I don't have to worry too much about issues caused by over-use. It would probably be a completely different situation if you were looking to maintain a permanent setup though. The links for everything I used are in the description box of this video and in the description box of my "Easy DIY Solar Tracker" video ( th-cam.com/video/5xh7wapF_pA/w-d-xo.html ). The links under this video are more of the external components while the links under my "Easy DIY Solar Tracker" one include the specific parts that I used to make my solar panel stand. Thanks for watching and commenting! I really appreciate it :) Edit: Let me know if you have any more questions. I'll do my best to help.
Well done! Vertical tracking is more significant then I thought. Suggestion to consider. You can estimate the actual sun energy watts/m^2 by measuring the short circuit current (ISC). Find the ISC value for the solar panel at Standard test conditions (STC). Lable on the back of the panel or datasheet of the manufacturer. Then use this equation Sun Energy = G G = ISC/ISC_STC * 1000 The units For G are Watts/m^2 Then plot the ISC data instead of the watts delivered. Might give an interesting result.
Hi Jessica, thanks for this valuable research. Can you show me the code for your tracker? I wonder, which value you used to make the panel follow the sun. I try to build the most cost effective one-panel-system, that can be put on a balcony
My understanding is that a tracking system is not necessary or cost effective in every application. For ground mounted solar arrays it's cheaper to just add additional fixed panels to make up for the lost watts. With fixed panels there are no moving parts to maintain, repair or replace and the system as a whole is gobs cheaper, even with additional panels. For backyards with limited space and only a few large panels/arrays on poles a dual axis system makes sense. If you look at most big solar farms they are fixed arrays/no tracking.
15% to 26% improvement. Considering most Solar Panels are 19% to 22% efficient, I’d say with are larger array you would definitely compensate for poor efficiency of most Solar Panels even on a cloudy day. I have the best of both worlds, 90 % efficiency from my In Stream Hydroelectric generator, 24/7 365 days a year from the small river that runs through my property. My 500watt Solar panels is for the time my Hydroelectric is down a couple of times for Maintaining( at most 2hrs), I don’t use a Solar Tracker , I adjust the panel 3 times a day, Solar morning , Solar noon and Solar afternoon, for my lat and Lon here in Canada. I think if you had a large array you have to weigh the cost of a Solar Tracker to move those heavy panels around, not cheap for say a 1 to 2 kw array of Panels. I chose to retire and planned to purchase my 3 acres of land with a year round stream, and Greenhouses which runs a few small pumps for my Hydroponic Systems for Vegetable, which my 500 watt array covers quite well. I have plenty of power to run all the household Electrical devices, including charging my EV vehicle. You did an excellent job of The Data, and the numbers came out to where I suspected they be. So as long as you don’t have a huge heavy array I would say a small system and a cheap Solar tracker is worth while.
This is great data Jessica, how about you revisit it with a lumen meter sensor and give us some lux readings in there...oh data...lovely data and sensors. I feel this device would be excellent on a boat out at sea
That sounds super cool! I've never heard about a lumen meter sensor before, thank you for telling me about it. Haha I wish I could test it out on a boat!
my country trying to make all house use fixed solar panel. I said we need tracking solar panel. wish my tax payment used with efficient, thanks for the experiment report.
great experiment and data collection. did you account for the power used by the motors to move the panel and how did that effect the benefits of tracking? can it scale up to a 200w panel.
OK, cool. Now add a second panel at (say) 45 or 90 degrees, connect it in parallel with the first panel (use blocking diodes), and fix everything, no tracking. You should find you get about the same amount of solar energy as the tracking system, but without the cost of the tracking. The second panel is certainly extra money, but is generally not as expensive as the tracker. For full size solar panels they are actually a relatively small fraction of the total system cost these days, (although for your toy system that may not be the case.)
Well done this experiment. The tracking system allows an extra 25% on top of the constant high voltage production throughout the day. Which won't do these extra panels.
@@HansKeesom You're basically right. An extra panel will bring more energy but the imput won't be regular thought out the day. When the sun will set so the input as the panel does not follow the run of the sun.
Fixed systems should not be 'flat', they are at 45 degrees facing south for optimal sun exposure. You should be tracking energy spent on servo vs overall power efficiency of stationary vs tracking system. Results may surprise you.
So it means that if increase 24.56% more solar panel than our existing system, we can get output of single axis solar system. I think it is better way than moving system.
Arduino board use very little power, and motors don't run much. I guess 5Whh per day, but maybe as low as 1Wh (especially if you sleep the arduino for ~5mins between moves). About 1/2 a mobile phone battery a day.
yeah a like from me too, with the single axis orientated parallel to the ground, it will track the sun either east to west or from the horizon due south to its highest point/angle at midday. if you lower one end of that axis so that the axis is at an angle to the ground it will track the sun both at the same time. hmm I might not be explaining clearly what i mean , id give it a go if anyone interest but cant upload a picture or video. you could do it on your system by instead of haveing the two side aluminium towers equal height make one much taller than the other so the axis points down
All this can be made much, much easier. The easiest way is how an Optical Telescope basically works according to the 'Equatorial' principle. The equatorial mount has a north-south "polar axis" that is tilted to be parallel to earth's polar axis, allowing the telescope to swing in an east-west arc, with a second axis perpendicular to it so that the telescope can swing in a north-south arc. By swiveling the polar axis of the mount or mechanically moving in the opposite direction of the Earth's rotation, the sunpanel can accurately track the movement of the sun all day, easy by one clock on 24 hours time line. See the link for this >> en.wikipedia.org/wiki/Equatorial_mount#German_equatorial_mount
I've measured 38% when both axis tracking is done.
Well done! :)
Nice! Thank you for sharing your findings with me!
Thanks for that.
Excellent work. Very clear easy to read data. One of thee most well made videos on TH-cam. Would be nice to see tracking on two axis.
Thank you so much for the kind words!
Again as others have said, excellent work and excellent documented results.
I have a several of comments:
1) You should view another TH-cam experimenter who demonstrated a "genius setup" tractor of two large solar panels balanced via a hinge on a see-saw horse whose panel tracking is automatically done ONLY by an additional small pair of steering solar panels powering a $20 motorized actuator arm. No sophisticated computer serup!
It's an extremely simple setup. The key is to reverse the power leads from the small steering panels so to supply voltage in an additive/subtractive method to the actuator arm's stepper motor, by changing voltage director to the DC motor, as the Sun moves across the sky. Thus advancing or reversing the tractor's DC motor direction and the large solar panels position.
2) In your "fixed solar panel" experiment test you placed it totally horizontal, flat eg 0° degrees.
Whereas, in actual fixed solar installations installers set the fixed panel say at 32° deg angle to face the region of the sky where the maximum Sun tracks across the sky at higher intensity say 10 AM to 3 PM.
Perhaps if you had placed your fixed panel in a similar angle Sun facing way, it seems to me you would capture more solar power for the day.
Perhaps enough, where the power differences between fixed vs tracking would be smaller. (Maybe next time.)
3) My thought considering how complex and expensive Sun tracker systems can be to gain a 25% to 30% improvement, wouldn't it be simpler and more cost & power effective for home setups just to add an additional fixed non-tracking solar panel.
4) Again, you produced EXCELLENT data comparison results of a single tracker vs a fixed horizontal panel.
You Go Girl!!
- Paul
Hi, Paul. Thank you SO MUCH for the kind words and suggestions! I appreciate the support tremendously :)
Brad Cagle apparently invented the setup and has a video on it. Super simple, super genius!
Jessica, that's a real interesting and very clear study here. Thanks.
For those who are talking about adding extra panels. The tracking system allows 25% on top of the constant high voltage production throughout the day.
Which won't do these extra panels.
Great presentation! Thank you.
When there is not room for more panels this is the way to go.
Solar farms in the Northern US are using single-axis trackers.
Thank you, most clear and straight forward clip! It will be intresting to have a 3d tracking sistem :)
#rd tracker.. aka: solar farm. haha.. I have one and I'm impressed. I will get more when I get my own land.
Very, very well done! A controlled experiment with detailed scientific analysis of the collected real world data. A pleasure to watch & learn!
Great video, love the amount of data and presentation of it. Great job!
Good stuff.
Theoretically on a dual axis you would get 5-10% more as the sun moves over it move sideways or vertically for us planet side.
Theoretically the maximum is + 39.7%.
To give a little context, the ballpark figure that most people throw around for tracking systems is up to 30% improvement in harvest, so your results are pretty much in the ballpark.
lol..
Great Job... Would have like to see a comparison of 1 Axis and 2 Axis solar tracking efficiencies...
Great video. Nicely done. I do wonder if there would be a way to hook it a computer and record trends over time and compare that to weather conditions from a home weather station, use a photo resistor to record the suns intensity etc.
Hi Jessica. I have the Eco Worthy dual axis tracker. I have 2 arrays. All panels are identical; Trina 400w. 1st: 2 panels laying on the ground, tilted about 12" and facing West. 2nd: 1 400w panel on the tracker. It has been averaging just over 1 KWh a day.. 1.8KWh\312w, 1.16\320w, 1.12\317 for the past 3 days. Late yesterday after the sunset, I added a 2nd 400w panel to the tracker. It's now getting 1.24KWh. The 1st array is getting 890Wh and just 417w. So YES.. trackers work.. I have 6 new bi-facial 200w panels arriving on Friday (1200w) which I will mount on the tracker. Overall these 2 arrays make about 2KWh a day.. but that will go up drastically soon. I have a Victron 150\100 for the 2-400s and a Victron 150-45 for the 2nd one. I have a video on my channel of it.
You should do this same test with a dual axis tracker. I'm certain the numbers would be more..
Excellent Professional Video, content was sufficient, informative, and detailed. The actual data results speak for themselves. Now how about grabbing the data remotely via WiFi 2.4ghz on just the tracker and piping it back real time (every 3-5 minutes) to your Home router so You can monitor and track it on a Raspberry Pi attached to your home network? Great job, you will go far at this pace!
I really like this presentation, and good info. Just subscribed.
Great experiment, I never thought to do tracking for solar, thanks for sharing 👍
Glad you enjoyed it! Thanks for watching!
Usualy non-tracking sistems installing not in fully horizontal position, but with about 30 degrees to horizontal surface. I think in this case improvement will be less then 25%
Very interesting! Thank you for pointing that out :)
This is exactly what I was looking for
Shouldn't the fixed panel be placed at tilt angle?
Nice field test.
Can you repeat:
1. using a MPPT Charge controller
2. placing the non-tracking solar panel at the angle for maximum solar yield (i.e. latitude)
3. apply a constant load to the setup
Lovely experiment
Results will not change very much. Therefore, a waste of time, to repeat.
This is a great comparison, really enjoyed the video told me what i needed to know.
Thanks for making the comparison(s)
This is really important when solar pumping …but not a game changer if charging batteries. Best to over size system by 150 to 200% capacity for cloudy conditions and or mount extra panels to cover the full sun’s arc.
Great experiment! Considering how sharp power data changes in the early and late hours of the day where tracking makes a huge difference, I would only guess that the improvement percentage would be better for a higher resolution data/measurement.
Agreed! Thank you for watching :)
Wooooow! thank you for arranging this experiment
Thank you very much Jessica! Congratulations for your experiment! Only one thing I didn't understand: when it's cloudy, the generation is really zero? Thank you!
Thank you and yes that's correct! This solar panel is pretty cheap and small so on the days where it was really cloudy, it was unable to generate any power.
I would be very interested to see how a 2-axis tracking compares to the fixed 1-axis system that you show here. What formula or equation did you use the determine the area under the under the watts line on your chart? I presume you used a spreadsheet (Excel?).
The problem with trackers is a). the additional cost & maintenance &, b). the potential for damage due to strong winds. I live in the UK & we have short periods of ferocious gale force winds that would tear apart most tracking PV systems.
Could you detail the exact components you used (manufacturer, reference number & specification) & their costs please. I up-ticked your video; well done Jessica. Regards, JohnnyK.
Hi, John! I hope this helps!
I think explaining by text might be a little confusing and long, so I'll just link the spreadsheet I made for all my data collection here for you to see: docs.google.com/spreadsheets/d/1mXE6vnOvNZ5RhREiE107h2ph80cnrbCfERHAFbYU-xw/edit?usp=sharing
I totally agree that trackers have their downsides. Fortunately, I live somewhere with pretty weak wind and I use this solar panel setup every once and a while for fun so I don't have to worry too much about issues caused by over-use. It would probably be a completely different situation if you were looking to maintain a permanent setup though.
The links for everything I used are in the description box of this video and in the description box of my "Easy DIY Solar Tracker" video ( th-cam.com/video/5xh7wapF_pA/w-d-xo.html ). The links under this video are more of the external components while the links under my "Easy DIY Solar Tracker" one include the specific parts that I used to make my solar panel stand.
Thanks for watching and commenting! I really appreciate it :)
Edit: Let me know if you have any more questions. I'll do my best to help.
Well done! Vertical tracking is more significant then I thought.
Suggestion to consider. You can estimate the actual sun energy watts/m^2 by measuring the short circuit current (ISC). Find the ISC value for the solar panel at Standard test conditions (STC). Lable on the back of the panel or datasheet of the manufacturer.
Then use this equation
Sun Energy = G
G = ISC/ISC_STC * 1000
The units For G are Watts/m^2
Then plot the ISC data instead of the watts delivered. Might give an interesting result.
Thank you for watching and thanks for the tip!
Good video, have you thought about doing a dual axis to see improvement with a dual vs single and fixed?
I'm impressed! great job
Superb,
But did you deduct the power used by motor to direct the solar panel?
It's usually negligible, most commercially available trackers can support around 100 panels with a 300 to 400 W motor(runs only for few min every day)
Thanks for the tracking data and great video
Good job, interesting. Thanks for sharing.
Best demonstration
Hi Jessica, thanks for this valuable research. Can you show me the code for your tracker? I wonder, which value you used to make the panel follow the sun. I try to build the most cost effective one-panel-system, that can be put on a balcony
My understanding is that a tracking system is not necessary or cost effective in every application. For ground mounted solar arrays it's cheaper to just add additional fixed panels to make up for the lost watts.
With fixed panels there are no moving parts to maintain, repair or replace and the system as a whole is gobs cheaper, even with additional panels.
For backyards with limited space and only a few large panels/arrays on poles a dual axis system makes sense. If you look at most big solar farms they are fixed arrays/no tracking.
Great data! Thanks!
I will like to learn more on this analysis
Thanks for this video! Have you tryed to make doal movement on the tracking system? I am curious how much more efficient that would be😊
You can easily find that answer using GOOGLE ...
Excellent job
hey thanks have you tried this with a poly crystalline panel?
Can you please tell me specifications of your solar panel? How many volt & watt?
15% to 26% improvement. Considering most Solar Panels are 19% to 22% efficient, I’d say with are larger array you would definitely compensate for poor efficiency of most Solar Panels even on a cloudy day. I have the best of both worlds, 90 % efficiency from my In Stream Hydroelectric generator, 24/7 365 days a year from the small river that runs through my property. My 500watt Solar panels is for the time my Hydroelectric is down a couple of times for Maintaining( at most 2hrs), I don’t use a Solar Tracker , I adjust the panel 3 times a day, Solar morning , Solar noon and Solar afternoon, for my lat and Lon here in Canada.
I think if you had a large array you have to weigh the cost of a Solar Tracker to move those heavy panels around, not cheap for say a 1 to 2 kw array of Panels.
I chose to retire and planned to purchase my 3 acres of land with a year round stream, and Greenhouses which runs a few small pumps for my Hydroponic Systems for Vegetable, which my 500 watt array covers quite well. I have plenty of power to run all the household Electrical devices, including charging my EV vehicle.
You did an excellent job of The Data, and the numbers came out to where I suspected they be. So as long as you don’t have a huge heavy array I would say a small system and a cheap Solar tracker is worth while.
This is great data Jessica, how about you revisit it with a lumen meter sensor and give us some lux readings in there...oh data...lovely data and sensors. I feel this device would be excellent on a boat out at sea
That sounds super cool! I've never heard about a lumen meter sensor before, thank you for telling me about it. Haha I wish I could test it out on a boat!
my country trying to make all house use fixed solar panel. I said we need tracking solar panel. wish my tax payment used with efficient, thanks for the experiment report.
Its more cost effective to just buy more solar panels compared to using a solar tracker, especially if you want to have large scale solar arrays.
This is great!
That was very helpful.
Why fixed panel was horizintal? Do You live in/on equator? If not, optimum angle should be used.
kindly share how you connected the rest materials
great experiment and data collection. did you account for the power used by the motors to move the panel and how did that effect the benefits of tracking? can it scale up to a 200w panel.
More efektiv with tracker....👍
Do a vertical biracial experiment
OK, cool. Now add a second panel at (say) 45 or 90 degrees, connect it in parallel with the first panel (use blocking diodes), and fix everything, no tracking. You should find you get about the same amount of solar energy as the tracking system, but without the cost of the tracking. The second panel is certainly extra money, but is generally not as expensive as the tracker. For full size solar panels they are actually a relatively small fraction of the total system cost these days, (although for your toy system that may not be the case.)
That's definitely a smart alternative for practical uses!
Well done this experiment.
The tracking system allows an extra 25% on top of the constant high voltage production throughout the day. Which won't do these extra panels.
@@GGN-92 It's not AS flat output as solar tracking, but it's pretty good, you get a very similar curve.
@@GGN-92 Extra panels will do more then these extra 25%, up to 100%
@@HansKeesom
You're basically right.
An extra panel will bring more energy but the imput won't be regular thought out the day.
When the sun will set so the input as the panel does not follow the run of the sun.
Very nice!
Fixed systems should not be 'flat', they are at 45 degrees facing south for optimal sun exposure. You should be tracking energy spent on servo vs overall power efficiency of stationary vs tracking system. Results may surprise you.
good job!!
Super job
Thank you!
Thanks 👍
So it means that if increase 24.56% more solar panel than our existing system, we can get output of single axis solar system. I think it is better way than moving system.
you will never simulate the same curve with just 25 percent more panels
How can we transfer datas in wattmeter to a website to be observed ?
What was the power consumption of the tracking system?
Arduino board use very little power, and motors don't run much. I guess 5Whh per day, but maybe as low as 1Wh (especially if you sleep the arduino for ~5mins between moves). About 1/2 a mobile phone battery a day.
Thank you
It's fantastic
Anyone know how efficiency was calculated in this video?
what kind of sensor that track the sunlight route?
I'm using two photoresistors (also known as LDRS or light dependent resistors)!
Is this a net increase after deducting the power needed to operate the motor ?
yeah a like from me too, with the single axis orientated parallel to the ground, it will track the sun either east to west or from the horizon due south to its highest point/angle at midday. if you lower one end of that axis so that the axis is at an angle to the ground it will track the sun both at the same time. hmm I might not be explaining clearly what i mean , id give it a go if anyone interest but cant upload a picture or video. you could do it on your system by instead of haveing the two side aluminium towers equal height make one much taller than the other so the axis points down
Thanks for watching and thank you for the idea! You explained it very well and it sounds very interesting to try out!
But tracking system need external mechanical, energy consumption do they actually a benefit by tracking
I think the tracking system would have started off earlier then 7:30 AM.
awesome
How much electricity those motors use have you considered that
+
All this can be made much, much easier.
The easiest way is how an Optical Telescope basically works according to the 'Equatorial' principle. The equatorial mount has a north-south "polar axis" that is tilted to be parallel to earth's polar axis, allowing the telescope to swing in an east-west arc, with a second axis perpendicular to it so that the telescope can swing in a north-south arc. By swiveling the polar axis of the mount or mechanically moving in the opposite direction of the Earth's rotation, the sunpanel can accurately track the movement of the sun all day, easy by one clock on 24 hours time line.
See the link for this >> en.wikipedia.org/wiki/Equatorial_mount#German_equatorial_mount