Advice on getting power 250ft to batteries

[Ampster]

............

I hope to stay on the topic of the thread I started, and still hope for some direct answers to the questions I asked. I want to know opinions on the 6awg wire I have, and will it work? If so how should I wire the panels to work best thru the cable, and for the charge controller. I have to admit it is a bit frustrating to ask direct questions from those that know, then to read more side tracks then answers. I thought i would break down my questions into segments, starting at the source, the panel configuration, the long cable run, and the charge controllers ability to to get the batteries charged especially in winter. I will have other questions about,
.........

First, let me apologize for my part in the side tracks. It does take two to tango and the dance takes a while when you dance partner is long winded.. I did get a satisfactory answer from Bruce about how he chose the location he did. My takeaway is that it is worth the extra copper of you can accomplish your production goals. My guess is his production goal was "system" performance not just panel efficiency.

Specifically you asked about 6AWG and you.did a calculation showing less than 2% voltage drop on 600 volts. That looks to be fine. The trick is to keep the voltage high if you have a long run. It sound like your controller can handle the high voltage. I am not a big fan of direct burial cable because it limits your future options and plastic conduit is so cheap, especially compared to the labor involved in digging and filling a trench. Years ago when I was spending the money for trenching a new electrical service I also added a couple of 1" conduits for future TV cable, fiber optic or telephone or whatever the future held in store. It turned out to be worth the minor extra expense.

My suggestion would be if you are going to the trouble of digging a 250 foot trench put in at least 1 inch plastic conduit. You can always throw your direct burial cable in the trench. At least the conduit would give you an upgrade path if you wanted to add another string. My 2 cents

[In the Stix]

J.P.M Thanks for that advice. I will take the steps needed to get my direction, and various tilt angles as right as I can.

I hope to stay on the topic of the thread I started, and still hope for some direct answers to the questions I asked. I want to know opinions on the 6awg wire I have, and will it work? If so how should I wire the panels to work best thru the cable, and for the charge controller. I have to admit it is a bit frustrating to ask direct questions from those that know, then to read more side tracks then answers. I thought i would break down my questions into segments, starting at the source, the panel configuration, the long cable run, and the charge controllers ability to to get the batteries charged especially in winter. I will have other questions about, safety components, inverters, monitoring etc. I think I'm on the right track battery wise, but if not it would be great to know before I start this spring.

I am on a couple firearms/hunting related forums, and like to think I know my stuff pretty darn well. I purposely look for people who ask questions trying to gain knowledge, of various aspects, then try to answer their questions, and stay on the topic of the OP. I find it very interesting, and still learn a few things as I go. As you know, my knowledge in the topic of solar is very limited. I am the type of guy that likes to learn. If I had unlimited funds and could simply phone a couple companies, and tell them i want an expendable 15kw system, I still wouldn't without basic understanding. Please give me the benefit of your knowledge. I think with it I can achieve a good well designed system, at a price that I can afford.

Thanks Gord

[Ampster]

......
As for bragging rights, this rather conventional house has achieved ZERO CARBON
FOOTPRINT with all electricity and heat coming from the sun, mini-split heat pumps
making a huge contribution. Bruce Roe

Thanks for the explanation. Congratulations on the zero carbon footprint. I have a friend in Southern California who accomplished the same thing. Much easier to do there. If I remember correctly, in 2020 new construction in California will be required to be zero carbon..Stay warm.

[J.P.M.]

I very much appreciate the impute, and hope for more. Some in the form of this is what I would do with the panels, would be great as well. Here is what I took into consideration for panel placement.

1) The storage shed for solar, and back up propane line is situated in between a 500 gallon propane tank, and the cabin, approximately 30' from each. I did consider putting the storage shed near the panels, however winter access would be more of a challenge, but not my biggest concern because I anticipate some winter snow removal from the panels. My issue with the shed near the panels was running and extra 250' +- underground propane line to the shed for a back up generator. As it sits everything fits nicely. I have a buried propane line to the cabin, and another to the shed spot for the generator. I also have the underground cable from the shed to the cabin in the ground. I also thought about just running the genset up close to the cabin, but I want to charge batteries as well, when needed.

2) The panel placement gives me a wide open field facing directly to the south. They will be out of the way, and I have plenty of room for expansion. With the right mounts I can tilt for snow drop off, and some reflection from snow, There are no trees, poles or anything else to cause shading from shortly after sun up, to shortly before sunset in the winter, just the clouds. Cloud shading is why I am interested in optimizers. I just don't know how much they will help with that.

I need to deal with the long DC run, and I am hoping the 6 awg will be ok. The tristar 60 mppt controller states an impute voltage of up to 600v, Could I not run 10 or 12 Of the mentioned KuDymond 38 volt panels all in series, or for expansion ability run 2 x 5 or 6 in series then parallel at the output 190 volts and 18 amps for 10 panels. On calculator.net using 250' of 6awg they indicate a a voltage drop of 1.87%. I think I'm missing something here. In "theory" with my very limited electrical mind, I thought 30 of these panels would be possible.

Gord

No significant shade on an array means things can get simpler - as in no need for optimizers or micros for shade considerations. Fewer electronics to fail as well. KISS applies.

As for array orientation, if you are after maximizing annual production per installed STC kW, run PVWatts for your location. For ground mount and max. annual production per installed STC kW, I'd suggest starting with an azimuth of maybe 190 - 200 deg. and a tilt at local latitude. Do a few runs and zero in on the optimum azimuth/tilt combination. If seasonal adjustment is planned, rerun at tilts of latitude +15 deg. for winter and latitude - 15 deg. for winter. Do 3 runs, one for winter, one for summer and one for spring and fall. Some finagling is necessary. Exact dead nuts max. orientation is not necessary. This ain't rocket science. +/- 5-10 deg. for both az. and tilt is probably close enough and may well make construction easier/better/cheaper/faster.

[In the Stix]

I very much appreciate the impute, and hope for more. Some in the form of this is what I would do with the panels, would be great as well. Here is what I took into consideration for panel placement.

1) The storage shed for solar, and back up propane line is situated in between a 500 gallon propane tank, and the cabin, approximately 30' from each. I did consider putting the storage shed near the panels, however winter access would be more of a challenge, but not my biggest concern because I anticipate some winter snow removal from the panels. My issue with the shed near the panels was running and extra 250' +- underground propane line to the shed for a back up generator. As it sits everything fits nicely. I have a buried propane line to the cabin, and another to the shed spot for the generator. I also have the underground cable from the shed to the cabin in the ground. I also thought about just running the genset up close to the cabin, but I want to charge batteries as well, when needed.

2) The panel placement gives me a wide open field facing directly to the south. They will be out of the way, and I have plenty of room for expansion. With the right mounts I can tilt for snow drop off, and some reflection from snow, There are no trees, poles or anything else to cause shading from shortly after sun up, to shortly before sunset in the winter, just the clouds. Cloud shading is why I am interested in optimizers. I just don't know how much they will help with that.

I need to deal with the long DC run, and I am hoping the 6 awg will be ok. The tristar 60 mppt controller states an impute voltage of up to 600v, Could I not run 10 or 12 Of the mentioned KuDymond 38 volt panels all in series, or for expansion ability run 2 x 5 or 6 in series then parallel at the output 190 volts and 18 amps for 10 panels. On calculator.net using 250' of 6awg they indicate a a voltage drop of 1.87%. I think I'm missing something here. In "theory" with my very limited electrical mind, I thought 30 of these panels would be possible.

Gord

[J.P.M.]

Guess you have not been here long enough, to observe how many objectives J. P. M. and
I have enjoyed respectfully agreeing to disagree on. The original array here was hired in
2013, to get it done promptly and solve the paperwork hurdles. The system is out of sight
of the house, no solar on any of my roofs, net metering inverters in a shed.

This standard SW desert design in my opinion was far from optimum for the continuous
clouds and frequent snow here in NW ILL. Continuous observation, design, and
construction have been going on ever since. No argument that facing a panel south will
generate the most KWH, a very important consideration when panels were extremely
expensive. But now panels are cheap, and remember it is always going to cost more per
KWH at this location than in the SW. Primary considerations here have shifted to keeping
this max size inverter plant as loaded as possible, and to minimizing snow clearing
efforts and any other maintenance.

In getting this science project right, those objectives have been met under sun or clouds.
15KW of inverters producing 28,000 KWH a year is about as good as the SW desert systems
do, and the fixed system will easily out perform a tracker at this location. First cost is
higher, compensated in this case by huge doses of DIY. Snow performance is hugely
improved; while snow blowing some 7 inches this morning, I simply tapped on every other
vertically oriented panel and almost all the snow fell off, the earlier, not yet upgraded
arrays required significant labor to be cleared.

As for bragging rights, this rather conventional house has achieved ZERO CARBON
FOOTPRINT with all electricity and heat coming from the sun, mini-split heat pumps
making a huge contribution. Bruce Roe

Bruce: Thank you. The last word is yours.

Respectfully,

J.P.M.

[bcroe]

Is that it in a nutshell? I hope you can work out your issues with Bruce. You are sure spending
a lot of server storage on your issue with Bruce's panel orientation.

Guess you have not been here long enough, to observe how many objectives J. P. M. and
I have enjoyed respectfully agreeing to disagree on. The original array here was hired in
2013, to get it done promptly and solve the paperwork hurdles. The system is out of sight
of the house, no solar on any of my roofs, net metering inverters in a shed.

This standard SW desert design in my opinion was far from optimum for the continuous
clouds and frequent snow here in NW ILL. Continuous observation, design, and
construction have been going on ever since. No argument that facing a panel south will
generate the most KWH, a very important consideration when panels were extremely
expensive. But now panels are cheap, and remember it is always going to cost more per
KWH at this location than in the SW. Primary considerations here have shifted to keeping
this max size inverter plant as loaded as possible, and to minimizing snow clearing
efforts and any other maintenance.

In getting this science project right, those objectives have been met under sun or clouds.
15KW of inverters producing 28,000 KWH a year is about as good as the SW desert systems
do, and the fixed system will easily out perform a tracker at this location. First cost is
higher, compensated in this case by huge doses of DIY. Snow performance is hugely
improved; while snow blowing some 7 inches this morning, I simply tapped on every other
vertically oriented panel and almost all the snow fell off, the earlier, not yet upgraded
arrays required significant labor to be cleared.

As for bragging rights, this rather conventional house has achieved ZERO CARBON
FOOTPRINT with all electricity and heat coming from the sun, mini-split heat pumps
making a huge contribution. Bruce Roe

[J.P.M.]

Is that it in a nutshell? I hope you can work out your issues with Bruce. You are sure spending a lot of server storage on your issue with Bruce's panel orientation.

No, it isn't. I don't deal in nutshells. And to say (write) I have an "issue" with the orientation of Bruce's panels is not correct. I do not.

After being at it for over 40 years, I simply know, until disabused of the idea, that for the same gross panel area, way off south and multiple panel orientations such as Bruce has built almost never maximize annual solar radiation flux on his arrays or maximize electricity production per m^2 of panel surface, and so will not maximize economic return on the investment.

In that sense, which is what I took to be the sense of your incompletely explained and so possibly and easily misinterpreted use of the term "optimum orientation", Bruce's arrays are not optimum.

But that's not a criticism of what Bruce has done. I wouldn't have done it his way, starting off with the likely fact I couldn't and can't do what Bruce has done. But, all that matters not one whit. Not one. I do some eccentric stuff with alternate energy as well and folks think I'm a bit more than simply eccentric. I bet we're both having fun even if we go about it in different ways. I believe he has, and I hope I have made substantive contributions to the body of knowledge, or at least filled in a few cracks.

As for my response to your question, is what it is.

Your cutting and pasting of my response to your request for particulars leaves a lot out.

You asked "Can you provide me the particulars ?".

I took that to mean you wanted to know (from me) the background and more detail of why I wrote "it isn't".

I attempted to provide that information to the best of my ability and recollection to the extent I felt it warranted for a clear response, and as I felt time and effort permitted.

When someone askes me a question, I try to be respectful and respond and answer the question as best as possible.

I'd respectfully suggest that if you reread what I wrote and follow up on any questions it sparks in you brain that you might learn some of why I have the orientation/production opinion I have.

Also, others reading my response might have an opportunity to see that your statement about orientation may have some holes in it.

This is, after all, a place to learn stuff and exchange opinions.

As usual, take what you want of my stuff and scrap the rest.

But I'd respectfully suggest if you don't like what you get when you ask a question, that you consider being more careful about what you ask for.

J.P.M.

[Ampster]

........
Bruce's are fixed azimuth arrays of several orientations
......Bruce may have different opinions about this, ....

Is that it in a nutshell? I hope you can work out your issues with Bruce. You are sure spending a lot of server storage on your issue with Bruce's panel orientation.

[J.P.M.]

Perhaps I should have used the word "maybe". Can you give me the particulars? Or should I wait for bcroe to respond to a post that was directed at him

I respect Bruce and I'm quite sure he can speak for himself. Take what I write as background or do with it what you wish, including ignoring it.

But as you ponder what to do about what you may consider my impudence, also think about your question. If you do, you might come to the conclusion that most everyone else who's knowledgeable in such areas has reached as a matter of common sense: For any location that's shade free, when considering fixed or at least fixed azimuth arrays, there is one azimuthal orientation that optimizes annual insolation and probably a second (probably close to but not the same) azimuth orientation that optimizes annual system output. The case of seasonal tilts may help, but azimuth will stay fixed.

Finding optimum array orientation has been one of, if not the primary driving force behind modeling of solar energy availability and resource assessment for solar energy systems. "I want to know the best orientation for my collectors" is a phrase that's been around for a long time. That implies one orientation unless dual axis or gimbaled tracking is considered. Bruce's are fixed azimuth arrays of several orientations. For the majority of locations, that optimal azimuth is probably within 10-15 degrees of true south (or north in the southern hemisphere). Bruce has several orientations capable of variable tilts, most of them quite a ways off south, with some of them at 90 or 270 deg. azimuths. Now Bruce may have different opinions about this, but unless conditions are very unusual, any array with a 90 or 270 deg. azimuth, including his, for the same panel and panel areas he will never have as much annual insolation or annual system output as an equator facing array tilted at close to local latitude. Other considerations besides maximizing output may be part of the design process, and that seems lot of where Bruce's ideas are centered on, but your statement "Your case may be the same as the OP where the location of the panels is based on the optimum insolation" is, to the best of my knowledge incorrect. Or, if that was Bruce's intention, he got that part of it wrong.

Now I'm sure Bruce has a good time with his stuff, and I listen very carefully to what he has to say about EE matters as he knows much more about such things than I. In such areas I think he has a lot of correct information, a rare common sense approach and experiential knowledge. But in the area of resource assessment and optimizing collector orientation to maximize either annual insolation or annual output, I know more than some, and I know Bruce's stuff does neither - and I've told him that in the past, long before you showed up here, both by forum postings and PM's when they were still available. I just gave up ranting to him about it several years ago, figuring he either was ignoring me, or didn't care about it, or didn't want to get tied up in areas where he felt uninformed, or I was full of crap. Or, whatever.

So, before you get your knickers in a bunch and think I stuck my nose into what you may think is your private communication, know you're late to the party. Consider my comment to you "It isn't"as information you may find useful, or put it where the sun don't shine. In such things, and IMO only, and to your question, if his goal was to get systems that have either optimized annual insolation or maximum annual output, or even seasonal optimals for that matter via variable tilts, he didn't meet it. He's done a lot of very useful stuff, and I've learned from it, but optimizing output via orientation is not what's been attained.

Enough particulars for you ?

[Ampster]

It isn't.

Perhaps I should have used the word "maybe". Can you give me the particulars? Or should I wait for bcroe to respond to a post that was directed at him

[J.P.M.]

Your case may be the same as the OP where the location of the panels is based on the optimum insolation.

It isn't.

[Ampster]

For sure, a trade off against the price of copper. My panels are 500 feet from the house, I need to snow blow
a path back there on a regular basis. Bruce Roe

Your case may be the same as the OP where the location of the panels is based on the optimum insolation.

[bcroe]

On the other hand, especially in winter, having the batteries and electronics 230 feet from the cabin may be a serious disadvantage.

For sure, a trade off against the price of copper. My panels are 500 feet from the house, I need to snow blow
a path back there on a regular basis. Bruce Roe

[inetdog]

Here is one thing to consider. Your solar energy comes in big lumps mid day, your use is probably
spread over time at a much lower level. SO it would be most efficient to place the batteries near
where the panels need to be, so the peak power level can be carried efficiently to them. Your long
run then may be at a lower, longer interval power level. Could even be a 120VAC or 240VAC
inverter you remotely turn on, minimum current. Bruce Roe

On the other hand, especially in winter, having the batteries and electronics 230 feet from the cabin may be a serious disadvantage.