Need 20kW single axis tracker - any ideas?

[Kentucky Farmer]

I am looking for a high quality single axis tracker, somewhere around 20kW.
Most of the good looking products are only sold to utility scale and other large projects.
Do you know of a vendor or product line that will sell to a small project?
I'm looking for a very heavy duty and deluxe setup.

[littleharbor]

Something like this? huge tracker.jpg

[Kentucky Farmer]

That would work but I'm scared of heights.....
Actually, something like a single or double row on a common 4" square tube.
Who sells heavy duty tracker components, racking, controllers etc?

[bcroe]

The consumer suppliers say they can do tracking, but my experience is they can't do any kind
of practical, movable array. As shown above, they get elevated at higher latitude. Beat that
with a series of smaller arrays, but they need considerable space to avoid shadowing each other.

I wonder if you have actually come up with a configuration? I am now building a movable array
here from scratch, in 6KW increments. Bruce Roe

[peakbagger]

The reason you are having a tough time is the extra cost to track arrays is far more than the benefit you are going to get in output. Far cheaper to install additional panels. Wind loading gets significant and the structure needs to be quite beefy to keep alignment issues at bay. All Earth Renewables in VT make some beefy dual axis units that are rated for 120 MPH. They are quite popular in VT as the VT solar rules were effectively written by the guy that owns the company that makes them. For most folks outside of VT there is a significant premium for them but some folks with spare cash laying around buy them as they look cool in operation. The federal tax credits does pay for 30% of the extra cost.

[Kentucky Farmer]

Agreed about the cost.... we have years of side by side data between fixed and trackers. The objective is to broaden the power curve for a demonstration project. Single axis is what we need.

[J.P.M.]

Agreed about the cost.... we have years of side by side data between fixed and trackers. The objective is to broaden the power curve for a demonstration project. Single axis is what we need.

Where did the data come from ?

[AzRoute66]

Agreed about the cost.... we have years of side by side data between fixed and trackers. The objective is to broaden the power curve for a demonstration project. Single axis is what we need.

Interesting that a 20kW array demonstration would show something that a much smaller array would not.

[NEOH]

Up to 90 Panels x 300 watts = 27KW

http://patriotsolargroup.com/products/single-axis-tracker/#engine-tab-features

[bcroe]

Up to 90 Panels x 300 watts = 27KW link

That tracker has the panels perfectly flat at solar noon, fine at the equator. Here at 42 deg Lat it
would lose the advantage of a fixed panel tilted to 42 deg. To get tracking advantage AND keep
the latitude tilt, an end of the axis must go WAY up in the air, quite difficult for an array of any size.
Bruce Roe

[Kentucky Farmer]

NEOH - Thanks, that is closer to what I am looking for. Wish that product offered a 120-degree range like NexTracker and Soltec. I would prefer a single row for low profile and greater wind resistance.

BCROE - Agreed. We actually have a tracker site that slopes toward the South. Having said that, at our latitude (about 37) the larger utility systems are flat, single axis. I'm guessing that the late afternoon boost is a benefit, especially during the long days of summer A/C season. We might get some of the same effect with a fixed rack, facing slightly West.

[NEOH]

That tracker has the panels perfectly flat at solar noon, fine at the equator. Here at 42 deg Lat it
would lose the advantage of a fixed panel tilted to 42 deg. To get tracking advantage AND keep
the latitude tilt, an end of the axis must go WAY up in the air, quite difficult for an array of any size.
Bruce Roe

The OP stated "Single Axis Tracker" he did not state Tilt required for 42 Degrees - you made that up.

[bcroe]

The OP stated "Single Axis Tracker" he did not state Tilt required for 42 Degrees - you made that up.

Yes actually at 37 deg Lat mounting the panels with a flat axis would apply about a 0.8 efficiency
compared to tilted panels. Wonder what gain the tracker could provide against that? Maybe the
real reason utilities use the tracking, is so they can turn them to avoid snow. Bruce Roe

[J.P.M.]

The OP stated "Single Axis Tracker" he did not state Tilt required for 42 Degrees - you made that up.

I don't think Bruce made up the latitude of his location. I believe the point was that single axis (w/ N-S axis alignment) tilted at local latitude will probably produce more annual output than the same array size but with the axis same N-S axis of rotation being horizontal, but would perhaps require a beefier design.

All that however, says nothing about the likely, and at this point in the design, unknown lower cost effectiveness and increased maint. requirements of a tracking array vs. a larger fixed array.

[Kentucky Farmer]

I do a fair amount of solar research that is shared with the local utility.
Aside from the perpetual problem of solar intermittency, the daily demand curve does not align with typical fixed array output. We want to make that better.
Obviously, new storage technologies are where we need to be looking..... and waiting.
Personally, I am woking on PV to Heat Pump to Thermal Storage. Several companies are operating in this area and we can expect some exciting new products in the HVAC area.

In the meantime, we wish to demonstrate the ability to generate as much late afternoon PV power as possible - when summer A/C demand is the highest.
Thus, we want to evaluate a rugged single axis tracker.
I have a South facing slope that is 150' long. Horizon to horizon East-West exposure.

Thanks for any ideas.