I don't have any intention to run a mini split or AC, but I'm enticed by tracking because of my experience with my smaller portable single panel system.  Being able to tilt my panel towards the sun at 8:30 AM in November and start getting juice was eye opening.  The difficult to quantify benefits of less severe discharge depths on batteries have to be pretty significant.

http://www.sunfolding.com/

The home built tracker I made...  Well, it did work,  but using junk materials caused it to be a bit untrustworthy.  Dave Sparks told me that with the low cost of panels now,  it makes more sense to just add panels in the direction you need to add power in,  such as morning or afternoon.  I  agree. 

Passive tracking like Glen spoke of (an east and west facing array) is an easy way to get long hours of power without using the battery and less time using the battery. This can really help if you have the loads. This is really for people living in a home full time who have cooling loads in summer and fortuanate enough to live in a place that they may not need a generator for winter. Unless your cabin is going to become a place where you live I would think that you are overthinking this.

I have never liked the Zome Tracking system and always use Wattsun (Array technology). I am a dealer and get wholesale pricing for my clients. The Horizontal linear axis tracker I use holds about 4,500 watts of solar and I doubt anyone could build it themself and have reliability for decades.
Some large homes need two of these.  I hope this helps!

Quote from: flyingvan on December 23, 2016, 02:32:29 PM
http://www.sunfolding.com/

Any info on these? I had sent e-mail to them 6 months ago and never heard back. Looks like Utilty tracking which can very rarely make sense for Offgrid costwise. When I saw Al Gore on their web page I thought that was why I never heard back. Maybe I was wrong......

There is an installation using a bunch of these that I pass on the way to Los Alamos. It is interesting to see them at different times of the day and year. Every so often one of them loses track.

No, no further info.  My sense is it's past the idea stage and got enough funding to be developed into a concept.

When there is price and availability info, and an installation manual, then we can talk about field testing. The commercial/utility trackers are extremely reliable at this date and so half of the bragging on their website is not really accurate. If I hear anything I will let you know. If I can link this below it will show one of the 4,500 watttrackers I use. Delivered anywhere in the US continent for less than 3K$ and the same concept (HZLA) as the start-up you linked. They have been in Don's state since the early 80's. The link Don posted is not really how people do this anymore. I never used those Don because there was more to go wrong with a DA tracker. Anything outdoors with lightning can fail and Array Tek has been great with parts. I always say if a tracker fails, you have a fixed mount array until you fix it. None of mine have failed except a lightning strike that needed a new PCB.

The HZLA does not need the installer to use a ladder and in commercial apps a pile driver installs the mounting poles. The dual axis tracker does have a 40% harvest gain over the 25% for the HZLA. These harvests are for a grid-tie application. For offgrid it is the hours of additional power we care about because we rarely use all that is available. Once our battery is charged there is alot of unused energy left unused on the offgrid "table". This is often compensated for in winter

http://arraytechinc.com/duratrack-hzla-residential/

Solar panels on roof or on ground ?

Our first structure will be a gambrel roof barn.  Current plan is for the ridge to run almost N-S.  That could change.

The lower half of the gambrel roof is very steep.  Below it will be a shed roof, 3-12 or 4-12 pitch.  If I rotate the barn so the ridge runs E-W, would it make sense to put the solar panels on the steep barn roof, or does it make more sense to keep the panels near the ground for safe accessibility.

Hoping to learn from others' experience.

Thanks.

I prefer on the roof out of harms way. If you wire them decently you don't have to do much other than clean the dust off once in a while. Maybe a good spray nozzle on a hose could take care of that. If you have plenty of room, the ground is not bad either. Up to what seems best for you. I'm short on space so, roof it is. 

IMO, if you have ground space, stay off the roof. Easier, safer, fewer roof penetrations...

Thanks.  I think we will leave the barn orientation as planned, and put the panels on the ground.  We have room, I also dislike roof penetrations, and I am getting into the brittle phase of life.  We will have a couple dormers on the roof, and they also would have added complexity to putting panels up there.

Really appreciate the feedback.

 A good plumber can also minimize the roof penetrations if the roof slope is high. I got ours down to one 3" pipe for the whole house.
Glen, you don't have ground space?  Where did you move?  The ground is always best unless you are worried about theft and that is less of a concern with lower panel prices.

I have ground space but it is on steep slopes ...yes, Ideal for the needed angle for southern exposure, but... it is quite a ways for me to get wires back to the power center,  I don't want to put conduit and the trees are not spaced right for me to string wires through.

If I put it on the roof I don't have to worry about driving into it with a tractor or Bobcat, it is close to the batteries and inverter,  and I keep my open spaces flexible for whatever I may change my mind to. [ouch]

Not to mention you are a tad closer to the sun!   

Hey, I can always use an extra few watts a day.

Just making sure that you have not changed too much.       How do you like KRYZ ?

Same old me, Dave. Doing what I can to get by.

KRYZ.... what a fitting name for a Mariposa station. Actually I hadn't heard of it before you mentioned it. 

What do you think of it? I downloaded the app so I can check it out a bit.

By the way, going to daylight savings time really helped. I got enough extra solar I don't have to kick the generator on now. Maybe we should lobby to keep it year around.    

We like KRYZ alot and it is good for the town. We also stream the jazz station from
http://player.capradio.org/player.aspx?stationid=2

As for saving daylight, I am all for it........

I'll have to try to listen to KRYZ a bit more if I can get the volume high enough to hear it over the voices in my head. 

Quote from: glenn kangiser on April 03, 2017, 11:23:52 PM
I'll have to try to listen to KRYZ a bit more if I can get the volume high enough to hear it over the voices in my head. 

Is that the Alien thing or the Politic thing?  We can add on to the Fruits and Nut state the sanctuary state pretty soon. That ought to help fix the roads in our county right?

Well, Dave.  No hope for the voices I think.  As for the roads, I see they just added another 12 cents per gallon for them to steal from us, and misappropriate with all of the rest of the money they already have that isn't being used to fix the roads. 

Note that the road repairs already done were done by printed money for the recovery act by the feds after the bankers ripped us off and made our real estate not worth anything so they could buy it back for half price. 

They felt so bad they about us having nothing that they thought they should print money (increasing inflation) to repair the roads and add the high speed rail to nowhere so they could give us enough work to build up our savings so they can pull another scam on us in a few more years after our savings are built back up.

Next they will charge us for stopping the spraying of spreading chemtrails blocking our sunlight if we want to use our solar off grid power.   

Kind of Knarly last night with the lightning. 87 inches of rain, need any water? Darn, here it comes again more rain. I better go and see if the road is still there Nice that the sun charged the batteries this AM, did not expect that break in the Wx.

We also had plenty of rain. The battery has been doing pretty good with a bit of boost from the wind generator. I don't think it is working 100 percent. I need to pull it down again and put the new brushes in. A bit of snow mixed with the rain here today.

Quote from: Dave Sparks on April 08, 2017, 02:59:06 PM
Kind of Knarly last night with the lightning. 87 inches of rain, need any water? Darn, here it comes again more rain. I better go and see if the road is still there Nice that the sun charged the batteries this AM, did not expect that break in the Wx.

Planet is pretty messed up.  We had some record rainfall last week with 3 1/2 inches...  did you say 87 inches in a day?  That sounds biblical!