Grid-tied solar
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Loren49
Platinum Member
For anyone considering active trackers, don't do it is my advice. I did the first 3 of my 5 sets of panels on homebuilt trackers when I started in 2007, and panels were $4/watt.
Active trackers are a PITA to keep running....the control units were a perpetual problem (I tried 3 different brands), the linear actuators are good for about 2-3 years and you'll be replacing/rebuilding them, and so on. The parts I built were fine, the poles, the bearing for tilt, etc.....but the support stuff is dadgum nightmare.
Now that panels are a buck/watt and less, there is NO WAY I'd do a tracking system again.....and I didn't. My last 20 panels (5kw) are a fixed, ground mount rack built out of 1 1/2" galvanized pipe with 2" x 3/16's galvanized angle running perpendicular to the pipe for the panel mounting. Not one single issue with it.
SO, save yourself some grief folks....stay away from tracking systems.
My setup (added 10 more panels to the ground mount after this photo). You can see two tracking arrays, the third one is behind one of the others.
View of back on one tracker. Dual axis. Pipe is 8" sch40.
THIS is a WHOLE LOT better way to go:
Here is a study on trackers:
http://comp.uark.edu/~zbever/Paper.pdf
I read a number of years ago that in general if the added cost of a tracker was used to purchase more panels that the output would be a least as good. As price/watt of panels has continued to drop it seems this would more clear now. The biggest reason I would not use a tracker is because it has moving parts. Greatest benefit of solar over wind is no moving parts...nothing to break or malfunction.
Just my opinion.
Loren
houstonscott
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How do you account for all the commercial projects using trackers if it's not cost effective. You would think they made that factor in calculating a profit margin. HS
Loren49
Platinum Member
I think that location may have something to do with the choice. Also the actions of commercial developers very possibly do not relate to the home owners small project. Every personal and public/private (business, municipality, fire department etc) that I have seen (or by photo) have been fixed mount and the majority have been mounted on an existing roof.
I did a bit of research but if anyone is interested compare the cost of a full tracking mount and needed panels to a system that has 25 to 40 percent more panels and fixed roof mount. Also remember that though the trackers are in theory maintenance free I predict that over 20 years they will malfunction. For the home owner I still would go with the KISS plan (keep it simple stupid) -old saying from boating. I feel the issue of maintenance is much more relevant in areas that experience severe winters and icing. If I lived in an area with a warmer climate I would look at a tracker and do a serious comparison.
http://www.civicsolar.com/sites/default/files/documents/ac20energycomparison-madison-wi-43155.pdf
Solar Tracking Systems Gain Ground
A short piece from this site addresses the question:
To Track or Not to Track? | Home Power Magazine
Tracking increases production throughout the year. The amount of gain varies depending on the latitude, amount of unobstructed horizon, and local weather. Dual-axis trackers can provide up to 40% increased energy harvest compared to fixed arrays.
The downside of tracking is the higher cost of the tracker, plus the costs of concrete, labor, and burly structural components needed for the pole-mounted array. With active trackers, there’s the potential for failure of motorized and electric components. Repairs and maintenance costs can offset any production gains, as can storm damage, which is more likely with a tracked system. While inverters and PV modules carry 10- and 25-year warranties, respectively, most tracker warranties range from two to 10 years.
When PV modules were more expensive, trackers were used to squeeze more energy production out of the modules. Now that modules are much less expensive, trackers may not make sense for some applications. You’ll need to compare the cost and maintenance of tracker hardware to the cost of adding more modules to a fixed array to achieve the same energy output.
For commercial PV installations with an economy of scale that residential PV doesn’t have, tracking often comes out ahead—especially single-axis. For grid-tied residential PV systems, the best choice is usually a fixed array. With inexpensive PV modules, the most cost-effective approach—assuming enough available space—is to install more modules
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There was also information on that site about the benefits of a one axis (east west) tracker.
There is not a right answer and as trackers improve and become lees expensive and panel price comes down in will continue to be a moving target. One thing is constant, no moving parts vs moving parts.
Also, did you find information on percent of commercial installations with tracking vs fixed.
MossRoad
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Yep!
If anyone thinks the electric company is doing this to go green..... hahahhahahaaa that's rich! Oh! OUch, that hurts!!! hahahahaaaa
I&M (a division of AEP) is one of the largest polluters in the U.S. They are mainly coal burners, some nukers, a few hydro plants... but a solar plant in South Bend will work as well as an ice cream factory in Hades. They are doing it for the credits.
From this site:
https://weatherspark.com/averages/31561/South-Bend-Indiana-United-States
[h=2]Clouds[/h][COLOR=rgba(0, 0, 0, 0.701961)]The median cloud cover ranges from 41% (partly cloudy) to 100% (overcast). The sky is cloudiest onDecember 26 and clearest on July 17. The clearer part of the year begins around April 23. The cloudier part of the year begins around October 18.
On July 17, the clearest day of the year, the sky is clear, mostly clear, or partly cloudy 65% of the time, and overcast or mostly cloudy 33% of the time.
On December 26, the cloudiest day of the year, the sky is overcast, mostly cloudy, or partly cloudy80% of the time, and clear or mostly clear 20% of the time.
[/COLOR]
Redneck in training
Elite Member
you need to look when they were built. My guess is hey were built when panels were three times as expensive or they are built in places where land is expensive, that is just my guess.
Tracker makes more sense farther north because of in the summer the sun is behind of fixed array for several hours. Most commercial large scale trackers are single horizontal axis.
Loren49
Platinum Member
Solar power in Indiana - Wikipedia, the free encyclopedia
Solar power in Indiana has been growing in recent years due to new technological improvements and a variety of regulatory actions and financial incentives, particularly a 30% federal tax credit, available through 2016, for any size project.[1]
An estimated 18% of electricity in Indiana could be provided by rooftop solar panels.[2] In 2011, Indiana's largest solar installation was the six acre array located on the roof of the Maj. Gen. Emmett J. Bean Federal Center in Lawrence, Indiana, capable of generating a peak power of over 2 MW.[3]
A 17.5MW plant built at the Indianapolis airport in 2013 was the largest airport solar farm in the U.S.[4] A 9MW solar farm was built at the Indianapolis Motor Speedway in 2014.[5] Two more are planned, one near Peru, Indiana and a second one sited at the Indianapolis airport.[6] The 3.2MW Rockville Solar II is the largest solar roof installation in the state.[7]
Indiana | SEIA
Facts on the Indiana Solar Industry
There are currently more than 62 solar companies at work throughout the value chain in Indiana, employing 1,500 people.
In 2013, Indiana installed 54 MW of solar electric capacity, ranking it 11th nationally.
The 88 MW of solar energy currently installed in Indiana ranks the state 19th in the country in installed solar capacity. There is enough solar energy installed in the state to power 9,000 homes.
In 2013, $112 million was invested in Indiana to install solar for home, business and utility use.
The price to install solar on homes and businesses has dropped steadily across the country — by 8% from last year and 34% from 2010.
Solar power in Michigan - Wikipedia, the free encyclopedia
In 2002, Stanford R. Ovshinsky built a factory in Auburn Hills, Michigan to build low cost Uni-Solar panels using amorphous semiconductors that generate power in diffuse light.[1] Uni-Solar became the second largest manufacturer of thin film solar cells, after First Solar, and a developer of solar shingles before going bankrupt in 2012.[2][3] Michigan was ranked 14th among U.S. states for solar jobs in 2013.[4]
In July 2012, Michigan's largest rooftop array, 977.6 kW, was installed in Canton on the IKEA store.[5] Ford Motor Company and DTE Energy plan to build the largest solar plant in the state, a 1.04MW solar car port at Ford's world headquarters in Dearborn, Michigan.[6] Construction was scheduled to begin September 2014. The city of Ann Arbor announced plans to build a 1MW solar farm at the city airport in 2015.[7] The Ikea store announced an expansion of its existing array in 2015 to bring it to 1.2MW.[8]
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Solar is alive and well in your area. Check this site and see that Indiana and Michigan are in the ballpark with much of the US.
Average Annual Sunshine by USA State - Current Results
The proposed project is looking to be constructed in five different locations and as with wind projects the most favorable locations will be used. I think you're a bit negative on solar. The closest city to me has 46% annual sunshine and the cities in Michigan/Indiana show 51/55/ respectively and I have used mostly solar for 20 years.
Loren
SirReal63
Platinum Member
I wonder how much of that 88 mw is translated to actual production. There is always a difference in capability and actual production.
Loren49
Platinum Member
May be similar to this:
Where the Energy Goes: Gasoline Vehicles
Only about 14%–30% of the energy from the fuel you put in a conventional vehicle is used to move it down the road, depending on the drive cycle.
Where the Energy Goes: Gasoline Vehicles
The point is whether it works financially as far as a business venture and I bet it is a major part of many homeowner's decision. Some decide to go solar just because they think its the thing to do.
If you look at Dave's data you can calculate the actual output vs installed capacity percentage. Its dark half the time everywhere and at less than optimal angle some of the time and overcast to differing degrees. Amazingly it still works enough for many people and the last major spill was sunshine...(my humor for the day)
Loren
Loren
I see NREL has a new pvwatts calculator. PVWatts Calculator It's easy to use and nicer than the older versions. If you are considering solar pv, I would recommend running some test values.
I ran the pvwatts calculator for a 1,000 kw (1 mw) system in South Bend, IN based on a 40 deg. fixed, due south orientation, open rack mount using premium (19% efficiency, standard is 15%) panels. I left everything else at the default values.
pvwatts predicts an annual output of 1,248.8 mwh. If all 88 mw were installed at that location, annual output should average 88 X 1,248.8 mwh = 109,894 mwh.
That should run Mossroad's AC. :laughing:
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