quote:

Originally posted by offgrid:
We've been living offgrid for 15yrs, installed everything myself. Installed several offgrid systems for others.

Then your experience and knowledge probably most closely matches what my buddy will need.

quote:

Originally posted by offgrid:
Seasonal cabin solar systems are tough to design. Use lots of power for short periods of time.

Again: Actually: It won't use lots of power at any time. As I noted, earlier:

quote:

...lights, TV, and microwave, chargers for mobile devices, the WLAN I'm going to design, and, in the warmer months, the well pump. And surveillance system, if we put it in. Battery chargers for the ORVs, I suppose. Electric power tools on occasion.

That's it. All of it.

quote:

Originally posted by offgrid:
Having a 24/7 load with the surveillance system on a seasonal cabin, I would not do that, believe you're asking for problems.

What kinds of problems?

My current surveillance system at home, five cameras + NVR, has a total budget of about 80 watts--and that's at night, with the IR illumination running. The WiFi and LTE modem system I'll design for him probably a good deal less than that. Call it 200W, max.

quote:

Originally posted by offgrid:
You could have a quality generator auto start when the battery voltage drops to a set level. I would be concerned about the generator starting at -20 though.

Again: The cabin is occupied frequently during the cold-weather months, for either hunting or snowmobiling.

The only time the cabin is unoccupied for any length of time is during the warmest months of the season, which coincide with the months during which the solar array would be at its peak efficiency, and would be the months during which there'd be the lowest demand on the system.

quote:

Originally posted by offgrid:
Electronics or "Power Panel" inverter/charge controller... look at Outback Power. Outback is fairly easy plug and play. Solar panels, for the most part they are really all the same. I have Canadian Solar panels.

Noted. Thanks!

quote:

Originally posted by offgrid:
My panels and every offgrid system I've installed are on adjustable angle ground mounts. Much easier to install, easier to clean off snow, adjust for winter sun angle, snow slides off...

Yeah... problem with that is spruce/pine/fir trees. Lots of SPF trees. He'd have to establish sun angles/season and do some serious clear-cutting, I suspect.

I don't know as he'd be particularly interested in doing that to the trees surrounding the cabin.

quote:

Originally posted by offgrid:
Batteries, Concorde Sun Xtender. Insulated battery box with a power vent.

Noted. Thanks!

quote:

Originally posted by offgrid:
Suggest to find a local dealer to buy all the stuff. You probably won't know all the little things you'll need until you are 20 miles down that two track road!

I'll forward the recommendation, but, as I noted, earlier: He's an EE and we're both computer people, so we might choose to roll our own. Except the panel installs. That'll almost certain be contracted-out.

quote:

Originally posted by trapper189:
Is his property in the former Abitibi Paper Company land? Cellphone service is spotty on the main roads in parts of Northern Michigan.

I've no idea to whom the property used to belong.

quote:

Originally posted by armored:
Lithium would be the wrong choice for batteries in a cold climate. They can be ruined if they are exposed to temps below about 20 degrees. Lithium batteries that have to operate in cold temps need a heat source to keep them above the low temp threshold.

I did not know that. Thanks for the caution!

quote:

Originally posted by offgrid:
An AGM battery would be a better choice.

It sounds like AGM batteries would be the way for him to go? That's what I had originally thought.

quote:

Originally posted by wreckdiver:
Takes over 10" of snow to make my array slow down production.

Fascinating. I would've thought it would take a good deal less than that!

quote:

Originally posted by armedmd:
I would verify the construction of the pole barn first to confirm it’s strong enough to hold the panels on the roof in addition to the weight of the snow that falls.

I asked him about that when we first discussed the project. He assured me it was.

quote:

Originally posted by armedmd:
Good luck with the project.

Thanks!

Seasonal "rustic cabin" use, with a healthy budget? I'd go mobile/portable.

Goal Zero solar "generator", add on one or two expansion batteries, and bring those up with me when I visit. Take them with me when I go home.

Leave 4-6 solar panels permanently installed, with a cover.

Bring the battery packs up fully charged, top off where you can using the panels, supplement with a small inverter generator during foul whether.

Bonus points is that the solar generator and power packs can be used at home in an emergency too.

quote:

Originally posted by ensigmatic:

My current surveillance system at home, five cameras + NVR, has a total budget of about 80 watts--and that's at night, with the IR illumination running. The WiFi and LTE modem system I'll design for him probably a good deal less than that. Call it 200W, max.

Most of the systems/upgrades I've installed have been for existing homes. Existing systems are easy, new contruction not so much. Everyone says they don't use much power! We need to assign a number to that not much power. First thing I'll do is install a KW meter (old school glass KW utility meter/socket $150-200) on their system for 30 days. That is the only way I could properly spec out a system. That system spec is based on my 15yrs of monitoring our system as well as others. You could easily put a KW meter on the output side of your buddies generator to get a handle on use. Also suggest picking up a https://www.homedepot.com/p/Ki...itor-P4400/202196386 to check your surveillance system and other loads.

We use an average of 240KW a month. Our 48VDC system, 3300 watt array on an adjustable ground mount, 2500 watt wind turbine, 1250 AH battery bank. System is very well balanced. Water/well pump/pressure pump is our biggest draw.

For a 4.8KW daily use system here in sunny Colorado that will not rely on a back up generator. 48VDC, 3000 watt array on a fixed mount that is accesible for snow removal, 800 AH battery bank.

Hope all that helps you.

Our stuff

Outback inverters/charge controller
2 MorningStar diversion controllers dumping excess wind current into the two spec'd resistors. Each controller/resistor is wired independently for redundancy.
2 Bogart engineering Trimetric meters. Top AH/amp meter for the wind output, bottom battery state of charge/current in/out
Old school KW meter



Me on the left 85ft up installing my neighbors turbine. Easy day! Lots of work prior to this, footers, rebar, concrete, wiring...... Put alot trust in that crane operator!

This message has been edited. Last edited by: offgrid,

quote:

Originally posted by offgrid:

quote:

Originally posted by ensigmatic:

My current surveillance system at home, five cameras + NVR, has a total budget of ...

Most of the systems/upgrades I've installed have been for existing homes. Existing systems are easy, new contruction not so much. Everyone says they don't use much power! We need to assign a number to that not much power.

In this case that will be difficult to do, because all use and types of use are so intermittent. So I think the best we're going to be able to do is add up the loads and calculate.

As for the numbers I posted earlier, vis-a-vis the surveillance system: Those are real numbers, derived from a True RMS ammeter.

Thanks for your comments!

quote:

Originally posted by Aeteocles:
Seasonal "rustic cabin" use, with a healthy budget? I'd go mobile/portable.

Goal Zero solar "generator", add on one or two expansion batteries, and bring those up with me when I visit. Take them with me when I go home.

Leave 4-6 solar panels permanently installed, with a cover.

Bring the battery packs up fully charged, top off where you can using the panels, supplement with a small inverter generator during foul whether.

Bonus points is that the solar generator and power packs can be used at home in an emergency too.

This might be a good alternative, makes sense, no battery pack to maintain or replace, since it's empty what 2/3's of the year?

quote:

Originally posted by ensigmatic:

quote:

Originally posted by offgrid:

quote:

Originally posted by ensigmatic:

My current surveillance system at home, five cameras + NVR, has a total budget of ...

Most of the systems/upgrades I've installed have been for existing homes. Existing systems are easy, new contruction not so much. Everyone says they don't use much power! We need to assign a number to that not much power.

In this case that will be difficult to do, because all use and types of use are so intermittent. So I think the best we're going to be able to do is add up the loads and calculate.

As for the numbers I posted earlier, vis-a-vis the surveillance system: Those are real numbers, derived from a True RMS ammeter.

Thanks for your comments!

You're welcome!

Oversize the conduit from the power panel to solar array and leave a couple pull strings in the conduit. Also design the rack for more panels. Pick a combiner box that you can add strings to. Easy to do that upfront and doesn't cost much if needed in the future.

At 68,000 acres, the paper company land was the largest privately held chuck of land in MI. It was sold off in pieces as hunting land and we bought a piece. Cellphone service on our piece was non-existent. Your planning of this seems backwards.

First, does he have good enough data service to support uploading video surveillance?

Second, what does he plan on surveiling? Most of the two tracks are seasonal, nobody plows them.

Third, When will you start doing some of the basic math?

The northern part of the lower peninsula has a potential of getting 2.5 hours of peak sunlight a day in the winter. That's not including clouds or snow. You'll be on battery for 21.5 hours a day. Can the batteries even be charged enough in 2.5 hours to give you enough juice for the next 21.5 hours? I suspect the charge rates for lead-acid batteries won't allow the batteries to be charged to 100% in that time. You'll have to spec the battery bank such that 30% of its capacity will be enough to run the system. That way you can charge them from 50% to 80%. They'll accept more current and charge faster up to 80%. They last longer if you don't let them to get below 50%. I don't know what effect charging them to 80% has on battery life. I suspect you should charge them to 100% every so often to keep quotation in check.

quote:

Originally posted by offgrid:
Oversize the conduit from the power panel to solar array and leave a couple pull strings in the conduit. Also design the rack for more panels. Pick a combiner box that you can add strings to. Easy to do that upfront and doesn't cost much if needed in the future.

Noted. Thanks!

It occurs to me that, once constant power is available, it won't be long until somebody suggests "Gee, wouldn't it be nice to have a fridge, so we don't have to keep buying ice for the coolers in town?"

quote:

Originally posted by trapper189:
At 68,000 acres, the paper company land was the largest privately held chuck of land in MI. It was sold off in pieces as hunting land and we bought a piece.

Fascinating. Is there a map that shows what area was encompassed by that parcel?

quote:

Originally posted by trapper189:
Cellphone service on our piece was non-existent.

On his it is not. It is often marginal, but it's relatively solid.

quote:

Originally posted by trapper189:
Your planning of this seems backwards.

First, does he have good enough data service to support uploading video surveillance?

I believe he does. My plan calls for an LTE modem with an outside antenna placed at the most advantageous location. I believe I've checked our surveillance system using his WiFi hotspot, and that isn't even ideally situated. But I will double-check next time I'm up there.

Note: The surveillance thing would be just a gimme. A "would like to have." None of this is predicated on being able to do that.

quote:

Originally posted by trapper189:
Second, what does he plan on surveiling? Most of the two tracks are seasonal, nobody plows them.

Yes, we know. That's why his truck, which always goes in first, has a front-mounted winch (And he's occasionally had to use it to blaze the trail, so to speak.)

I think the idea is a few cameras around the immediate grounds of the cabin and pole barn.

quote:

Originally posted by trapper189:
Third, When will you start doing some of the basic math?

Once we've a handle on some of the basic fundamentals, which is the purpose of the thread.

quote:

Originally posted by trapper189:
The northern part of the lower peninsula has a potential of getting 2.5 hours of peak sunlight a day in the winter. That's not including clouds or snow. You'll be on battery for 21.5 hours a day.
...

Good information. Thanks!

I have a map, but it's a spiral bound paper book. It encompassed a piece of northern Presque Isle County and a good piece of Cheboygan County.