newbie, example first system review

Thanks for the feedback.  I think you are right, I do plan to add a basic system soon.  I just wanted to have my calculations double checked.  I might scale it back a bit to start.  I agree, it will be nice to have it all set up, and to be learning all about these systems in the process.

  hi brian,

  it looks like you are serious about going ahead with the system plans. much of your design is going to depend on the pv module location. that is.. the wire distance from the array to the controller. lets say for example your barn is orientated with its four corners north, south, east and west
and we can mount that module on the south corner at the proper angle and obtain a full solar window all year long there (see fig.3-5 and 3-7 pages 33 thru 36 of pdim) high enough so that we avoid head damage. and have our charge control setup inside that corner of the building only ten feet away. or a more conventional roof top mounting with the controller 50 feet away. lets look at those wire run examples for 10 feet vs 50 feet in this example. (see table 9-5 pg 97)when we look at the voltage (%2) drop tables for 8amps at 12vdc we see we are good for 12 feet with #10awg and need #4awg for 49 feet. thats not too bad, but lets say next year we would like to add on and max out that 25amp controller. we can do that no problem with #6awg at ten feet but would need no less than #2/0 awg cable for that 50 foot run! so brian, i ask.. how does your site survey look?

 depending on the above lets look at some of the components to build this system. first off that kyocera module. i love the new look of that d.blue line and i'm getting so i can spot them at 100 yards. never had my hands on one yet, but looks good and is a proven cell poly/multi. vs thin film. looks like this line should be around for a while. (i would double check when ordering) also has a friendly j box vs sometimes difficult techno wacko connectors. nice aluminum frame..not much to not like.

 gotta go for now.. check out chapter 7 pages 73-82 and check out this link.
 http://store.altenergystore.com/Charge-Controllers/Solar-Charge-Controllers/MPPT-Solar-Charge-Controllers/Blue-Sky-Solar-Charge-Controllers-MPPT/Blue-Sky-Solar-Boost-2512i-25A12V-3-Stage-Charg/p4618/

 also consider,

http://store.altenergystore.com/Meters-Communications-Site-Analysis/Meters-Battery-Monitors/Ammeters-Voltmeters-Battery-Monitors/Bogart-Engineering-Tm-2020-Trimetric-Meter-Battery-Monitor/p254/

  there may be some real big advantages to going with mppt with this setup.

 more latter, dave

Thanks for the suggestion on the MPPT controller.  It sounds like it might be a better option in terms of efficiency. I originally selected the PVM controller because I had read it was the standard type of controller and less expensive.

I had also considered a battery monitor, but wasn't sure how necessary it was.

As far as my site.  One side of the barn faces directly south.  The roof on this side of the barn is sloped at approximately 45 degrees.  My latitude is 42.5 degrees, so this is close to optimal.  I'm thinking the roof would be the best option because of the potential of shade at the ground level from some trees.  However, putting it on the ground might make the installation much easier. I also don't like the idea of having to make holes in the roofing material.
Either way, the length of wire should be relatively short.  The barn has a second story loft, so the cable from the panel on the roof to the controller could be kept close to 10 feet.  Or if there is spot at the ground level without shade I could also run the wire into the barn at less than 10 feet.  So, I think the wire runs can be kept short.  I didn't mention the wiring in my earlier post, because I still need to do some more exact measurements once I decide exactly where to place everything and then determine the wire gauge.

Thanks for the help.

 looks like you lucked out big time with the roof slope and orientation. nice when things work that way..

"I had also considered a battery monitor, but wasn't sure how necessary it was."

 brian, i suggested the monitor because i am sold on the idea of seeing exactly whats happening to every piece of equipment and every variable in the changes that occur throughout the charge and discharge cycles, as the clouds roll by and the temperature changes, as the loads are switched on and off. you can get a real feel for whats occurring and why. this is in itself the most excellent tutor i have encountered while playing with all this renewable equipment. chances are that you will never outgrow this monitor and my hat goes off to anyone who can. also if you trade that $112 controller for the $165 mppt version you are giving up that limited display info from the go power pwm unit..and we all like to look at some pretty display.

 some thoughts on a battery choice..now this is my opinion only so take it as such. those expensive agms are super choices..but, may i suggest that you start out with an el cheapo marine deep cycle "hybrid" battery as a disposable learning tool? at fifty bucks for a group 27 battery you can't go wrong. and if we kill it within six months i bet we get more than a fifty dollar education from the experience. i know of people that can kill a battery in six weeks! i also know of folks that can make them last for ten years! experience and knowledge will make you one of the folks in the latter group.

 also with an inverter choice..thats alotta clams for a dinky little micro inverter. i would be tempted to go the el cheapo route there as well. something like a $40 throwaway 400watt modified sine wave unit. the thinking here is you will most likely grow out of that 200ish watt pure sine wave inverter and 100ah battery bank very quickly when you see what you have done and what you are capable of.

 on that note- i would strongly reccommend one of the classes there in hudson ma. you are a candidate for that pv 302 class imho. (jumping ahead of those first two courses)

http://workshops.altenergystore.com/PV-302-Intermediate-Photovoltaic-Design-and-Installation-Sat-Feb-28-Mon-Mar-2/e57/

 if you look into this class, double check with the instructor for a waiver to take the advanced class without the basics classes. (looks like you have all that covered)

 cheers, 73 dave