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Dual Axis Trackings Systems

DEGERtraker 5000HD – Dual-axis, active <pdf>

DEGERtraker 9000NT – Dual-axis, active <pdf>

--> Watch DEGERtraker Movie <wmv>

 

 

If you are currently considering a ground mounted tracker, the following must be considered:

  • Do you have a large open area? The largest tracker is about 40' long and 30' high.
  • Is the land on which you plan to install the tracker 'solid'? It should not be swampy or subject to shifting.
  • These large structures are not allowed in residential areas.
  • There needs to be land flat and stable enough for our flat bed/crane to drive over, as it accesses the installation site.
  • Proximity to your Hydro Meter and electrical panel need to be considered, as the farther these are away from your tracker the greater your trenching and wire expenses will be.
  • Check the building code wind speed values for your township. Wind Speeds must not to exceed 60mph for DEGER 9000 Trackers. If your wind speed values are higher than this, you will have to go with a smaller tracker.

 

Should I Over-Invert or Over-Panel?

With the advent of the new OPA rules, it has been deemed that over-panelling will not be allowed. Thus, both the inverter value and the value of the sum of the solar panels cannot exceed 10kW. However, there is a move in the industry to put forth a position paper to counter this ruling. So, even though the rules are clear that, currently, over-panelling is not allowed, we have chosen to leave this section in, in the event that this rule is over-turned.

There seems to be some confusion about over-inverting/over-panelling. Before I explain, I will define what these terms mean. If you had a 10kw solar system that had a 10kW inverter and the wattage of all your panels equalled 10kW, you would not be over- inverting nor would you be over-panelling.

  • Over-inverting:  11kW inverter with 10kW of paneling
  • Over-panelling: 12kW of panels with 10kW of inverter power

The Ontario Power Authority (OPA) is very clear when they state that one of these elements, either the sum total of the panel wattage or the kW value of the inverter must be equal to or less than 10kW. So, this means that you can increase the value of one of them, but not both, if you want to qualify for a microFIT Conditional Offer.

Since we live in Southern Ontario, our latitude is such that, even on the brightest of June days, the sun will never directly shine over-head onto the panels. Due to this fact alone, 10kW of panelling in Southern Ontario will never produce 10kW of energy. Couple that with the fact that the sun angle only gets worse as the seasons progress (fall/winter/spring), you now have a compelling argument to over panel. Experts in the solar industry are suggesting that the best combination is a 10kW inverter paired with 12kW of solar panelling. If you put anymore panels on you would waste too much energy in the summer months, as the inverter will only process 10kW of power, even if you made 11kW.

At 12kW, your system will make you the most amount of money with the least amount of waste. You will be far more productive when it is cloudy and during the non-peak seasons (fall/winter/spring).

Conversely, if you kept the panelling at 10kW and switched to an 11kW inverter, your panels would be lucky to make 8 or 9kW of energy and you would have an 11kW inverter.... For what reason? Why would you require an 11kW inverter to process 8 or 9kW of energy? The inverter can process 30% more power than it is rated for. So this situation is definitely inverter-overkill and a complete waste of your money!

What about when I use a dual-axis tracker? They are able to increase my power production by 45%! Is this not a case for over-inverting? As you can see in the chart below, the 45% power increase comes from the fact that the tracker increases power production in the morning and in the evening. You will notice that the tracker cannot make the panels produce 45% more power during the peak 'noon' time. The tracker produces slightly more power at 'noon' because the fixed system is limited by the roof angle, which may not be optimal. The tracker can find the most optimal angle. However, it cannot make 10kW of solar paneling produce 14kW of energy. If it could, these trackers would be miracle workers and the inventors would be in Tahiti!

So, once again, we are back to 10kW of panelling in Southern Ontario will not produce 10kW of power. You are still better off to over-panel on your tracker.

  

Power Production Comparison:

Fixed Installed System (ex. Roof Top) VS DEGER Tracker

 

 

Fixed Ground Mounted VS Tracking Systems?

A Fixed Ground Mounted System Is less expensive to install. However, the rate that the OPA is paying for any ground-mounted installation has been lowered to $0.445/kWh of energy produced. To compensate for this lower pay rate, one should attempt to produce as much power as possible. A dual axis tracking system solves this problem. They cost more in 'upfront' money to install, but, in the end, they make more money. DEGER has stated that their ground-monted tracker will produce 40-45% more power than a fixed solar system.

 

More Money in The Winter!

Snow coverage is never an issue! Each tracker is equipped with a snow sensor that tells the tracker when it should dump the snow that has accumulated on the panels. If there is still some sticky snow on the panels, you can manually brush the rest of the snow off. The trackers are close to the ground and, unlike those poor 'roof- top' people, you won't have to risk falling from great heights to clear your panels! So, trackers make more money in the winter than the average fixed system. Just so you can have some real data, I will compare two solar systems that are just down the road from each other. The largest factor in the poor performance of the roof top system was the snow!

  • Deger tracker with 9.6kW of paneling - produced 647.99kW of energy (January 2011)
  • 10.56kW roof top system, directly facing south with no shading - produced 36.61kW of energy (January 2011)

 

The DEGER Tracker Follows the Light!!

Most trackers have Astronomical control systems. This means that a computer tells the tracker where to shine your panels based upon your longitude, latitude and the time of day and year. This does not take into account varying light conditions, due to reflections off of snow and cloud cover. Study the diagrams below and see how the DEGER tracker creates more power than an astronomical tracker, because it follows light intensity.

 

With bright sunshine: The DEGER tracker aligns itself with the brightest point in the sky.

 Note: In the following diagrams the astronomical tracker is grey and the DEGER Tracker is orange.

 

Snow: The tracking system will optimally use direct light irradiation, as well as the energy of reflected light.
 

 
 

Scattered clouds: Direct solar radiation and defuse light are used optimally.

 

Overcast sky: The system detects the brightest spot and directs itself accordingly.

 

 

Varying light conditions: In solar parks, the light conditions vary for each tracker, due to differing cloud conditions. The individual trackers align themselves optimally to the brightest light source. This guarantees the largest possible energy gain.

 

 

Installation Process

All of the bases used for our DEGER tracking Systems are cast off site, under controlled conditions. This ensures that the mast is perfectly straight and that the concrete has cured properly!

 

Here the bases are waiting in the yard for delivery. Note the Deger 9000 base weighs 42 000lbs and measures 3mx3mx3m. The DEGER 5000 base weighs 18 600lbs and measures 2.2mx2.2mx2.2m. Wow!

 

A flat bed truck, with a crane unloads the bases and helps to assemble the tracker unit.