For an updated explanation of what a solar tracker is and how it works, read our 2020 story here.
Other related tracking system stories:
A version of the article first appeared in a blog by mounting provider Solar FlexRack. Read the company’s blog here.
Solar trackers are rising in popularity, but not everyone understands the complete benefits and potential drawbacks of the system. Solar panel tracking solutions are a more advanced technology for mounting photovoltaic panels. Stationary mounts, which hold panels in a fixed position, can have their productivity compromised when the sun passes to a less-than-optimal angle. Compensating for this, solar trackers automatically move to “track” the progress of the sun across the sky, thereby maximizing output.
It’s a fantastic system for energy output, but there are a few considerations to bear in mind before pursuing one for a particular jobsite.
- Trackers generate more electricity than their stationary counterparts due to increased direct exposure to solar rays. This increase can be as much as 10 to 25% depending on the geographic location of the tracking system.
- There are many different kinds of solar trackers, such as single-axis and dual-axis trackers, all of which can be the perfect fit for a unique jobsite. Installation size, local weather, degree of latitude and electrical requirements are all important considerations that can influence the type of solar tracker best suited for a specific solar installation.
- Solar trackers generate more electricity in roughly the same amount of space needed for fixed-tilt systems, making them ideal for optimizing land usage.
- In certain states, some utilities offer Time of Use (TOU) rate plans for solar power, which means the utility will purchase the power generated during the peak time of the day at a higher rate. In this case, it is beneficial to generate a greater amount of electricity during these peak times of the day. Using a tracking system helps maximize the energy gains during these peak time periods.
- Advancements in technology and reliability in electronics and mechanics have drastically reduced long-term maintenance concerns for tracking systems.
- Solar trackers are slightly more expensive than their stationary counterparts, due to the more complex technology and moving parts necessary for their operation. This is usually around a $0.08 – $0.10/W increase depending on the size and location of the project.
- Even with the advancements in reliability, there is generally more maintenance required than a traditional fixed rack, though the quality of the solar tracker can play a role in how much and how often this maintenance is needed.
- Trackers are a more complex system than fixed racking. This means that typically more site preparation is needed, including additional trenching for wiring and some additional grading.
- Single-axis tracker projects also require an additional focus on company stability and bankability. When it comes to getting projects financed, these systems are more complex and thus are seen as a higher risk from a financier’s viewpoint.
- Solar trackers are generally designed for climates with little to no snow making them a more viable solution in warmer climates. Fixed racking accommodates harsher environmental conditions more easily than tracking systems.
- Fixed tracking systems offer more field adjustability than single-axis tracking systems. Fixed systems can generally accommodate up to 20% slopes in the E/W direction while tracking systems typically offer less of a slope accommodation usually around 10% in the N/S direction.
Overall, solar trackers are highly efficient installations and are a great fit for both large and small project sites given the proper location and site conditions.
Reading through the comments I do not see anything about the support structures required. If you have just a tilt tracker the solar panels can be mounted on a single pivot axis that could be simple hinges along one edge of the solar panel or a central pivot. Then all that is required is a single or double actuator to do the tilt. It is important to make the system strong enough to take not only the weight of the panel(s) but also other loads including wind and snow. If using a pan tracking arrangement you need a vertical pivot. This will require a heavier support structure and heavier foundations or other fixing. Even with a moderate size of solar system the design loads can be several tons.
As we go from lower to higher latitude,with EW tracker : generation & PR would be higher or lower
Qwik E. Mart says
As we go from lower to higher, dot on head would be higher or lower?
Bill Dean says
All great questions. Mine is a little simpler. Are solar trackers covered under the 30% tax credit?
I’m looking to go solar soon. So can someone answer this question quickly?
Kelly Pickerel says
Yes, they are covered.
Kirsten Regala says
Hello Bill, can you email your mobile number to me for more details about the 30% Solar rebate program. Here’s my email firstname.lastname@example.org
Russ L Russell says
Mark Gurney’s DIY system looks pretty good for a residential set-up. However, I do not have a “Truck Differential” so I have to find an alternative. Can anyone advise of an “off-the-shelf” tracker system to employ for a small residence in Northern Arizona? Probably will use an array of panels (maybe 6, 8, or 12) to power up a residence, shop, and greenhouse.
Giorgio Demurtas says
We make control systems for any type of solar tracker.
Get in touch with email@example.com and we can see what is best for you.
Here you can see photos of some of our customers’ solar trackers: http://www.ingdemurtas.it/en/solar/solar-tracking-installations/
Why on earth do you need solar sensor with the system? You don’t know how to calculate sun offset based on date/time/location? That’s not a good introduction to your systems..
Ray K. says
Just my thoughts, by using a sensor and moving to where the sun is, removes the need for an on-board computer to do the math and remember formulas and the necessity to make sure date and time are set correctly or harvested from external source. I would think simpler would be cheaper.
Alex Liu says
Did you ever hear of an helio tracker? Think of a sunflower, this flower points toward the sun as it grows. If you are able to mirror a natural event mechanically, why not make it instead of spending the effort of calculating when and where to turn the solar panel.
Bret Tschacher says
Well as someone that has lived in the country for a long time, I have seen sunflowers facing west, north, south, east randomly at any time when according to popular beliefs, they should all be facing the sun and following it ! The term Sunflower has more to do with the appearance of the flower than the flower tracking the Sun ! Helio is a Greek or Latin word for Sun I think, so a tracker makes sense to raise the output without installing more panels. However, anytime something becomes more complicated, well we all know where that leads to. Nothing comes for free, not even energy from the Sun when you need to use it for anything other than to see be during the day. It doesn’t take much calculation to aim during the day unless it is cloudy in which case you’re not going to get much output no matter where you aim. A dual axis system can double output of the single axis system over the total W/hr annually, so why not make use of it? All it takes is double the working code and double the mechanical components, along with a bit of extra space when working with larger systems as they need to be spaced more due to shadowing at various times, winter and daily. Positioning panels diagonally can reduce shadowing along with allowing movement around the panels to be increased up to a point.
HI, I am trying to get information about vertical sun-tracking solar panels, I am studying the possibility of installing them in a building wall. Is it possible? Has it been done? Thank you
Ozan ATICI says
We have a 0,5MW solar project which requires single-axis tracer. Firstly, we need 1 full complete system sample for single-axis solar tracking system including galvanized steel channel supports, transmission tracking system etc. 3×3 horizontally oriented system is enough for us.
Is there anybodoy to help us?
Steve Foster says
If you need help with that feel free to contact me and we can help you or guide you in the right direction.
I am doing a project on soiling in solar panles.I need to design a solar tracker for it.Can you please tell me way to design it.
Joel Huff says
Our company specializes in trackers, especially dual axis and have been doing it for 30 years. Feel free to contact me for more info.
Don Whyte says
that would be http://www.solarsunworld.com right?
That’s great marketing Joel. Then it is all salesmen this, and middlemen that, when you go to their website. They specialize in trackers yet don’t sell any? 30 years of experience would tell you that you need to have a product on your showroom floor when you send customers to your showroom floor? 30 years of experience would get you to make sure you gave customers the right phone number or address? Remember when there were successful professionals in this world, before marketing took over? This is what you get with marketing majors, journeymen who are qualified because they dug trenches for the big unions for 6 years, and subsidized businesses.
Hi Steve, I’ve been using an Off Grid design at home (Sri Lanka) using a primitive design of solar tracking for my 14 X 12 volt DC – 45 watt panels during the past 3.5 years. I have arranged the panels in arrays and have 4 arrays. The initial system had 4 arrays & 4 X 12 volt DC Wiper motors. Now I have tweaked it to work through 1 such motor. During the past few years I have learned a heck of a lot; burnt Inverters (12 volt DC / 220 Volt AC); burned Solar Charge Controllers, but heck, the journey was more interesting than my destination, where I am, right now. I have friends who supply the grid as Net Metering is available, but they sit in the dark everytime there is an outage. I think that Net Metering is a gimmick of all Government’s to get people to invest in solar. I thank you for the very informative / useful article. All success, Mate.
This page goes over the Zomeworks passive tracker. https://www.solaris-shop.com/blog/the-zomeworks-passive-solar-tracking-mounting-system/
Mark Gurney says
I have built a DIY solar tracker, using a truck differential with steel and concrete foundations.
My tracker controller got water in it so I’m just rotating it in the morning and at lunchtime.
The panels were in the same position fixed for a year and the difference of being able to rotate the array is massive.
I can hold the house (summer) from 7am to 8pm without drawing the batteries.
300 Ah at 48V holds the overnight requirements without going below 50V, so batteries should give a longer life.
I have drilled holes for the vertical adjustment which is adjusted once a month, I really cant not see the finanical payback of going for automatic two axis. If anyone wants details markbgurney@ gmail.com
Mark Gurney says
Photos of my array and other projects
I have heard that a solar Tracking system is not covered for 30% federal tax credit ??? Can someone clarify this for me…… I’m thinking of getting a tracking system……Need PROOF —- DOCUMENTATION
Gary W. says
Has anyone tried a DIY tracker? I’ve done some research online and it appears that there are several methods discussed about building this with an arduino. Example here: Arduino Solar Tracker. Any advice on any other systems?
This website has a great guide for tilting angles by location, month, and season.
mavis liu says
One question:the axis number of tracker normally is 1 or 2,I know.While which one is better/popularity in the market?Customers choose them depends on what reason?Could you please help us?
I want to know the steel structures used in their single or dual axis solar tracker.
Can you send me the contact of their supply chain ?
A solar tracker system needs competive and stable support from steel fabricator.
Besides ASTM material, GB is also suitable.
Mohamed Yossif Abdel-Mola says
I want to know the types of control systems that used in tracking system,
and how i can use PLC as controller in single axis solar tracker
Sundar Ganesh says
Steven. I did the Solar tracking with PV panel project in three mode of operation,
1. Azimuth & Altitude Dual axis mode,
2. Real time zonal mode
3. Night light Street-lamp focusing mode
I`m getting major Output energy per day,what i desired before starts this project, but i cannot establish this project-idea, to the market, because Climate condition in India is not bad and the initial cost is higher than the non-tracking mode in India. Do u have any Idea to establish in normal weather condition?
I’d like to know more about your project.
Would request you to share your contact details.
Sir, I am from India and have another doubt in my mind. I have to present a final year project in my college and the time duration for that is 6 months. I am planning on making a prototype for sun tracking solar panel (single axis using maximum voltage method). But many students argue that tracking sun isn’t beneficial as it increases the cost by adding stepper motor, sensors,control systems. Also to overcome shadow effect , land requirement is more. So in what way can I convince them that tracking method is beneficial? How can I convince them that tracking method generates profit for larger solar plants?
Steven Bushong says
Hi Rajas. The financial gain from the increased efficiency the trackers provide must offset the added cost of installing them in the first place. Often, trackers are used in multi-million dollar utility-scale projects. Developers planning these projects will spend $100,000 or more on financial/technical studies to determine whether a tracking system is a good idea. So if a company is willing to spend that kind of money to ensure a good investment, it’s clear the answer is to your question is not a simple one — and must be found on a project by project basis.
Steven Bushong says
Hi Thomas. I haven’t heard of this company before — possibly because they’re based in Taiwan. But I’m interested in learning more.
Kayla R says
Hi Steven. Thanks for sharing such an informative article. I am researching on Dual-Axis Solar Trackers market in the U.S.. I am looking for well-known manufactures that make Dual-Axis Solar Trackers in the U.S., and if Dual-Axis Solar Trackers are imported from other nations, I would like to find out names of exporting countries. Would you able to help me out? Thank you.
Steven Bushong says
Hi Kayla. A good starting point is our racking and mounting models chart. Select “tracker” in the system type option: https://www.solarpowerworldonline.com/racking-mounting-selection-app/
Ghazi Ava says
hello kayla ,, iam from kurdistan and iam student in the university of duhok i study electrical and computer engineering and my project is to design dual axis solar tracker and i finished my project
Bob Sampson says
What is the ideal tilt for stationary mounted solar panels facing due south (in the northern hemisphere)? Is it the same as the site latitude? What is it for panels facing slightly off due south, such as SSW?
Steven Bushong says
Hi Bob. I’m getting you an answer to this question. Stay tuned!
Steven Bushong says
Hi Bob. I received the following answer to your question from Solar FlexRack:
“The closer you are to the equator the
flatter the panel will be. Florida for example is 10-15 degrees, then
as you get farther away the tilt angle is larger. In Canada it’s around 30
degrees. If you are not facing true South that will not really affect
your tilt but mostly the output from not getting concentrated direct
sunlight. SSW will still by the same tilt but less output.”
Bob Sampson says
Steven, thank you for that answer. So is it site latitude minus 11.75 degrees (so that the sunlight would be incident normal to the panel surface at local solar noon at summer solstice)? That would make the ideal tilt for my latitude about 28 degrees, which is about 10 degrees more than my roof tilt. Do roof racking systems typically allow you to tilt the panels at a different angle than the roof? That would really help them to shed snow in winter.
Steven Bushong says
Hi Bob. I don’t recall a sloped-roof mounting system that delivers additional tilt. This is not to say it doesn’t exist. If I were to guess why one doesn’t exist, though, I’d say it’s probably because the additional cost required to design and install a mount like that would not be returned very quickly due to increased performance, as increased performance would be marginal.
Regarding your other questions, this website seems to be a good resource. We are also working on an article about this subject.
Steven Melton says
I built one! Im in the process of getting a patent for it. Be on the watch for a low cost tracker called Ridge Tracker. 🙂 I think it’s a real game changer as you can zero out an average electric bill with 14 panels!