Dennis Mono

Jay Angler wrote:

Dennis Mono wrote:...To Generate 60% more energy per Year, you simply install a Dual Axis-solar Radiation Tracker (DART), that follows the Sun from as earl as 5:30AM to 8:00PM, depending on your Latitude.

I can see something like this if space is really limited. What I see in my area, is that now that panels are relatively cheap, they just put them on different angled/direction roof surfaces, so that they cover more times of the day and year.

As David B said: "Installed once and maintenance free (or virtually) operation for its life span." In our wet and occasionally windy environment, I can't imagine a tracker like that not running into maintenance issues.

Hi Jay,
95% of Customers are Rural, and install there System themselves, as most Farmers have Equipment & are relatively Smart, DART unit is a large Meccano set, and only engage an Electrician to Wire up the Inverter & PV wiring.

There are a Lot of Shonky DAT Manufacturers out there, flogging Outdated Equipment, and that is what causes major issues & breakdowns, Using cheap DAT Controllers & Linear Actuators is the Cause of most problems.
You only get what you pay for.
Thanks for your input.
Cheers Den.

David Baillie wrote:
Dennis, The link kind of reinforces what I said above. It makes sense to me and I can admire the tech (but distrust their 60% figure) while not being willing to commit to it. If the system was for me and I had a single smaller array due to lot size or solar availability I would consider it. For my clients? Nope.  

As an installer I can tell you it rings all kinds of service technician alarm bells in my head. Cost per hour to have someone like me out to site is free for the first year , $75 per hour after that if I installed the system, $100 plus if someone else did. The clock starts when I leave home. Off grid arrays are generally in remote areas which means said technician will be traveling for hours. If you are lucky you bring all the parts with you and can diagnose and fix it in one shot. In reality nobody has all the right parts. So second trip with more travel time. You end up trying to present a $1000 bill for a $100 part replacement. So that in a nutshell is why the larger array that does not move is generally preferred.  There is a lack of qualified technicians out there for everything mechanical electrical electronic. I try to simplify and keep my systems as resilient as possible. Its a design philosophy at the end of the day.
Cheers,  David  

Hi David,
The 30% increase is based on Fixed Panels Generation, and comparing Generation using either GPS & Time Tracking, Both inferior to Radiation (Light) Tracking !
However, I should have said; Up to 60% increase in Energy Generation over 12 months !
The 60% figure would be in a perfect situation, and obviously a lot Further away from Equator the better the results.

As for Servicing, DAT or DART units, Yes Cheap Equipment is what causes the reluctance to install them, as well as the Installation of a Foundation needs a Hole dug in the Ground, and Trenching to where the Batteries & Inverter are installed...  Thus requiring an Excavator to save the Manual work.
The problems that can occur, is if the Wires coming from the Light sensor is Not protected for the first few cm, we have had two cases where Galahs or Cockatoos have Chewed the wires, but that only stops the Racking from Tracking, until repaired.

There are DART units that can be Installed without a Foundation, and can be fitted atop a Shipping Container, of bolted to a Concrete slab or Flat Roof.
https://www.micropowergrids.com.au/_SOLAR_GENERATION/1.DART_Commercial/03.DART-4/001.ROOF_DART-4.html

However, I do understand your concern, and DART's are Not for everyone, and largely a lot of Older people go for them, as they are a lot easier to Clean the solar panels, than climbing on the Roof.

There is so much BS about OFF-Grid & ON-Grid, as ALL Solar ...inc. Battery Systems are Installed Behind the Grid (Meter Box), so logically they are all OFF-Grid.
The only difference is that OFF-Grid inverters don't have Islanding Protection !
Making it Smarter to install an ON-Grid inverter that have Anti-Islanding relay protection, then the Customer has the option to use the Grid to Charge the System, or use a Generator !

Cheers Den.

David Baillie wrote:
All the research I have seen claims a 30 percent increase for dual axle trackers. They have lost favour here due to their high maintenance requirements.
I do live at 45 degrees so that is a huge ark in summer and challenging temperatures swings in the winter so it pushes the mechanisms hard. If you are the type of person who can change a control board, a dead sensor and an actuator you stand to gain some production. If you have to call in a technician every time a component acts up then no.  For my thinking  A good portion can be made up with a manual seasonally adjusted array angle. For the rest add panels which are cheap and do not require any maintenance. Installed once and maintenance free (or virtually) operation for its life span. Its a case by case thing though.
Cheers,  David B.

The most Common problems we have encountered with Old designed Dual Axis Tracking (DAT) systems in Australia are;

1) Cheap Linear Actuators fail at around 10 years, these were mostly 12V Actuators, that did not have an External Motor &/or used Plastic Gears !
Solution: Use 24V Double Slew Drives, as these will commonly outlast your lifespan, as they move slowly, and will Not wear out the internal metal Gears.

2) The other Common Failure is the DAT Controller that use Relays may/will Fail at around 4 years, Relays can burnout & either Not work, or get locked on & damage the Racking or wiring.
Solution: Use a Controller that uses Automotive Mosfets, these are superior to cheaper Relays.

3) Many old DAT units did Not use an Anemometer (Wind Sensor) , that automatically Lays the Racking Horizontal (Flat), to avoid Damage to the Racking & solar panels !
Solution: Fit either a Digital or Analogue Wind sensor.

4) Analogue Stop Sensors can Fail like Relays, especially if Not Water proof !
Solution: Fit Magnetic Stop Sensors, and Silicon over the connectors, to better weatherproof the switches.

5) GPS or Time Tracking is Inferior to Radiation (Light) Tracking !
Solution: Purchase a 4 Direction Light sensor that uses 4 miniature solar Cells, NOT the LED light sensors, as they are inferior when it comes to Accuracy.

That pretty well cover what to avoid when purchasing a DAT unit.

We have only found One Hi-Quality DART Controller, it is a Polish Made REI DART Controller.
https://www.micropowergrids.com.au/_Wiring_and_Equipment/DART_Controllers/_Light_Sensor_DART_Controller_Module_type-1.html

All this conversation is missing one important point;

If the Solar Panels are NOT perpendicular to the Sun, you are loosing up to 60% of the Energy you could be Generating per year !

To Generate 60% more energy per Year, you simply install a Dual Axis-solar Radiation Tracker (DART), that follows the Sun from as earl as 5:30AM to 8:00PM, depending on your Latitude.
Where the Further South or North of the Equator, a DART unit Generates Energy for a longer time.
NB: Radiation Tracking is Superior than either GPS or Time Tracking, as in Cloudy periods, they point the solar panels to Dark Clouds covering the Sun, whilst Radiation Tracking will rotate the solar panels to the Brightest area of the Sky.

Yes, DART units have a Higher upfront Cost, however, the Additional Energy is Generated using approx. Half the Solar panels for the next 30+ years.
DART units are commonly mounted on a Pole, buried in the Ground, and have a wind sensor to lay the Racking Horizontal in Hi-winds.


If purchasing Bi-facial solar panels, make sure they are Double Glazed, as they are not only Stronger, they also dissipate Heat better.
And for those wanting to Generate as much Energy as Possible from the Rear of the solar panels, you can cover the ground with White Stones or anything that is a White or Silver material, as that in a perfect situation will Generate up to 30% more Energy from the reflections.