# Cabin Off Grid.......What can we do for $4,000????



## Hiram Maxim (Jan 3, 2012)

My friend has a Cabin that is totally "off the grid" in the Upper Peninsula of Michigan.

He has 2 Propane Generators (primary and back up) that power his 3 bedroom, 2 bath, 1100 sq ft prefab Steel sided cabin.

Has an 80% propane heater and a VC Intrepid II for Our heating pleasure, so no worries there.

He is kicking around the idea of either some type of solar or wind generated system to supplement electrical use while the generators aren't running.

His budget is $4,000 total for an inverter, batteries, solar panels, turbine, etc.

Does anyone have some ideas of what can be done for this amount?

Where does one even start?

I appreciate any advise.

Thank you, Hiram


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## peakbagger (Jan 3, 2012)

A friend has similiar camp up in northern NH. He installed a battery bank, charge controller and inverter. When he arrives for the weekend, he charges up the batteries with the generator and then runs off the batteries for the rest of the weekend. It cut his fuel usage by two thirds as there is minimal standby loss from a battery bank. It also keeps him sane as he doesnt have to listen to a generator idlingI havent seen the system for awhile but I believe he did put some solar panels up to trickle charge the system when he is gone. When he is using the batteries, if he is going to run a high load like a circular saw, he usually turns on the generator. 

If you do elect to go with this type of system by batteries designed for this service. THis is not a place for Walmart deep cycle batteries. If you are not prone to doing maintenance, get some gel cells, they are more expensive but standard lead acid batteries need to be equalized ever few months and the water level needs to be checked. Gel cells are also a lot more tolerant to cold then lead acid. Two brands that I know of are Deka and Concorde. 

Some of the solar retailers sell packaged kits of components that are matched.


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## kenny chaos (Jan 3, 2012)

I know'd a man who ran his dairy farm off a generator which ran only in the 
morning for the milk machine and he'd do any heavy tool use needing to be done while a battery bank was charging
to run his meager energy use the rest of the day and night.
It was way cool and cheap.
Kenny


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## EatenByLimestone (Jan 3, 2012)

Is he up there often?  If it is only a weekend thing he can probably get by with more batteries and less solar panel.  That should give him the most bang for the buck.  He can most likely add a panel here and there later on to up his production if needed.  

Matt


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## mbcijim (Jan 3, 2012)

You can buy individual 235 Watt panels (commercial grade) for around $400.  Pricing is down to $1/watt ($235/panel) on large systems so maybe with some searching he can find prices that low.  No idea how much an inverter that small costs.  

Before he invests in solar without battery he should look at when it produces power and see if it meets his needs.  In the peak of summer I start producing minimal power around 8:00AM and it dies completely by 5:30.  Substantially less so in the winter.  

Don't know anything about battery so I can't help you there.


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## woodgeek (Jan 3, 2012)

He could read about this stuff at a forum: http://www.wind-sun.com/ForumVB/forum.php 

Not as active, but almost as nice as this one.

Flooded lead-acid (not maintenance free) are the cheapest up front and to run.  There are well defined ratios of panel amps to battery bank amps that he doesn't want to stray too much from.  An off-grid solar watt-hour costs about twice as much as a grid-tie watt hour to produce.  The batteries cost, and they eat about 25-30% of the energy between going in and coming out.

If the guy is handy, and comfortable with the (low voltage, high amperage) wiring, he can probably put together a system with 500-1000W of panels, that delivers 500-1000 kWh/yr of off-grid solar elec.  If his gennies make a ~5 kWh/gallon, this system will save him 100-200 gallons fuel/yr.  Or more if he runs a lot of standby/idle.

In a weekend cabin situation, I would (as noted earlier) go with a bigger bank and a smaller panel.  Theft of panels is also a concern if left unattended.

He will want to buy a high current charger to recharge his bank off his generator.  I like these: http://www.rvpartscenter.com/ProductDetail.asp?PID=54667&SID=66&DID=145&CID=475

The inverter is the hardest choice: does he want to wire a lot of stuff on 12V, or keep everything 120V, with some inverter losses and standby losses....


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## Hiram Maxim (Jan 3, 2012)

Great Info Folks......Keep it coming !

Right now its more of a weekend place but there are times when he is up there for a week at a time, and eventually it will be a Summer retirement destination. 

It sound like a battery bank being charged off the generators is a great start.

 I will be helping him as much as humanly possible both in research and installation. 

While I'm fairly handy I certainly don't know everything. :cheese: 

I sincerely appreciate every ones ideas and input thus far

Hiram


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## Poultry Farmer (Jan 3, 2012)

I live in the heart of the Michigan UP, and I use five 15 watt Sun Force amorphous solar panels charging two 125 amp-hour 12 volt Wal*Mart marine batteries pushing an 800 watt Cobra inverter on a 12 volt Flexcharge timer with 40 amp automotive relay.  This combination powers a 12 volt  one joule Patriot fence charger and two 13 watt CFLs (60 watt equivalent) for my pastured poultry operation.  A 3000 watt generic generator is used to recharge the batteries when needed.  I spent about $600 on the package, not including generator.  

According to the Department of Energy, the Michigan UP only gets 4.5 hours of effective sunlight per day.  I have found this number to be generous, as there are days that go by when it is quite cloudy and my batteries are receiving very little charge.


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## kenny chaos (Jan 3, 2012)

It may be better just to make the place non-electric.


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## EatenByLimestone (Jan 3, 2012)

It really depends on what he wants to power.  If it is only a few lights, the system won't cost much at all.  It's only when you start getting into well pumps and such that it would get expensive.  

Matt


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## Ehouse (Jan 5, 2012)

For short stays, to run just a few lights, charge the batts. at home and bring 'em with you when you go to camp.  Eliminates theft also.

Ehouse


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## Fi-Q (Jan 5, 2012)

A hughe killer can be the well pump (If needed). It all depends on your electrical need. Depending on the situation 4000$ can suit a lot of cabins I know off, but a very few comfy coittages.  But it'S true that as a start a good battery bank with a pure sin wave inverter and maybe 200 watt of salor, with a good charger to suplement the charge with the genny is a pretty good start and you can get a decent kit for 4k$


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## begreen (Jan 5, 2012)

Ehouse said:
			
		

> For short stays, to run just a few lights, charge the batts. at home and bring 'em with you when you go to camp.  Eliminates theft also.
> 
> Ehouse



That's how our friends illuminate their yurt. It's a pretty good system.


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## semipro (Jan 5, 2012)

Fi-Q said:
			
		

> A hughe killer can be the well pump (If needed). It all depends on your electrical need. Depending on the situation 4000$ can suit a lot of cabins I know off, but a very few comfy coittages.  But it'S true that as a start a good battery bank with a pure sin wave inverter and maybe 200 watt of salor, with a good charger to suplement the charge with the genny is a pretty good start and you can get a decent kit for 4k$



If the well pump is a big issue you could install a larger storage tank and then just run the generator to fill it up when needed.  Pressure tanks aren't that expensive and you can use more than one if needed. 

I like the idea of some PV with battery storage and a generator for topping off, backup, or heavy loads.  

A solar water heater might be a good investment also.  You avoid using your PV or gas to heat water that way.  If you need to heat water it far more efficient (cost and otherwise) to heat water with sunshine.


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## jebatty (Jan 5, 2012)

For usable lighting only, can't beat these: NoKero. About 6 hours of light from a charge. These have become our emergency lighting for our house when the grid goes down.


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## Ehouse (Jan 5, 2012)

You could use a solar well pump or windmill pump to trickle fill a storage tank instead of a whole panel/batt./inverter/charger system, or use a hydraulic ram in the right situation.  Then use a hand pump or treadle at the sink, or pump to an elevated tank with a drain line for cold weather.  Those NoKero lites look great!  I think point of use electricity generation is a good way to go;  high tech with less complication and lower cost.  All DC, so no inverter losses.  Propane fridge/cook/heat.  not much to steal either.  Its almost impossible to keep people off your property these days.  If you decide on an inverter setup, don't forget micro-hydro.

Ehouse


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## jebatty (Jan 5, 2012)

With solar panels, use micro-inverters. A location near me gets 2x to 3x the output with micro-inverters when any shading or partial snow cover affects the panels.


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## peakbagger (Jan 5, 2012)

By the way Sun Electric down in Miami Florida sells packages and low cost solar panels, they have very ppor customer service but if you dont need UL certification they are hard to beat. I am waiting for delivery for 23-215 watt panels from them that were 76 cents per watt.


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## semipro (Jan 5, 2012)

peakbagger said:
			
		

> By the way Sun Electric down in Miami Florida sells packages and low cost solar panels, they have very ppor customer service but if you dont need UL certification they are hard to beat. I am waiting for delivery for 23-215 watt panels from them that were 76 cents per watt.



Made in China?


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## peakbagger (Jan 5, 2012)

The panels I bought were the last Evergreens (I think they were made at the plant in Germany). Usually Sun electric buys surplus and overstock from north american manufacturers and a lot of time they get cosmetic seconds. On occasion they buy rejects and re-lable them. They sell to a lot of latin america and caribean countries where there isnt a need for UL. They recently had some rejects without frames and junction boxes for even less.


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## semipro (Jan 5, 2012)

peakbagger said:
			
		

> The panels I bought were the last Evergreens (I think they were made at the plant in Germany). Usually Sun electric buys surplus and overstock from north american manufacturers and a lot of time they get cosmetic seconds. On occasion they buy rejects and re-lable them. They sell to a lot of latin america and caribean countries where there isnt a need for UL. They recently had some rejects without frames and junction boxes for even less.



I had a look at their site.  Its got me thinking....


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## peakbagger (Jan 5, 2012)

Just make sure you understand the basics before buying panels. A lot the current panels are high voltage set up for high voltage grid tie systems. If you just want to charge a 12 volt battery, a 48 volt panel isnt going to be a good match unless you buy a more expensive charge controller with a MPPT set up. 

One of my arrays is set up with 20 - 12 volt panels wired in series in cold sunny conditions they can put out 400 volts. I hope to upgrade with the new panels so someone is going to get a deal on a pile of 12 volt panels.


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## frizman86 (Jan 15, 2012)

Hi I am new to this site and like it already. I am in the process of installing 3kw's worth of solar pannels on the gerage. The way I am doing it is I have bought 3X6 inch solar cells off of ebay. you can usualy get them for around .50 cents a peice and then just solder them to together to make 36 cell pannels to make a max of 18vdc. This would be plenty to charge a 12v battery bank. Though my system is different I am going grid tie. you can pick up alot of things off ebay. Also I would do some home work about what you plan on running. I say this because if you plan on running a alarm clock you will have to use pure sine wave inverters, which cost a lot more. If not the just regular sine wave inverters are a lot cheaper. 

For me since I am going grid tie I have to make sure all of my stuff meets michigan codes. But with you, you can get away with using cheaper components, since it is not grid tie.


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## kenny chaos (Jan 15, 2012)

Hi Friz and welcome..............home.
Kenny


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## peakbagger (Jan 15, 2012)

By the way, Sun Electronics dropped the ball, I had an order number and assurances they would ship but it sounds like other folks didnt get their panels despite paying for them. They did ship some so it wasnt outright fraud but more like incompetence.

An update, after numerous calls and finally getting someone to answer the phone. I did get my 23- 210 watt panels.. It took a month after the original ship date.


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## Hiram Maxim (Jan 20, 2012)

Keep em coming folks!

Fantastic information......  

Really really appreciate the input


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## Cowboy Billy (Feb 8, 2012)

Howdy Hiram

   The first thing he needs to do is figure out how much power he needs. What is he going to be running and how many watts it needs to start what ever he is going to run.

  The hart of the system is the battery bank if its not big enough to run everything it just won't work out. If he is mainly going up weekends it should be big enough to run two days. Also in cold weather the batterys don't put out as much power so it needs to be over sized if using in the winter. Also the batteys need to have enough to power to run the inverter at full power. Lets say you are using a 5000 watt inveter on 12v. That would require 416 amps for as long as you are using that much power. 

   I feel its more important to get enough battery and inverter first. And worry how to charge it second. And the bigger the battery bank the better if you batterys are just enough to run your outputs they are going to cycle more and build more heat and will severely cut their life spans. 

   As far as charge controllers I personally would not bother with anything other than a MPPT. While they are 2-3 times the cost of others I feel they are more than 3 times better. The cheep charge controllers just cut off any voltage past what charging voltage you need and wastes it. With a MPPT controller you can run much higher voltage than the battery and it uses it all. Having higher voltage to the controller allows you to charge the batter on cloudy low light days where with a cheep controller you would get nothing. With a MPPT running higher voltage you can run smaller wire from the panels to the controller for the same wattage. Which really becomes important if you have a long run from the panels to the controller. And where you put the panels is very important especially in winter. I have a tree line 200+ feet from my panels but in the winter the sun is so low its shaded most of the day.

   I prefer one forklift battery to a battery bank. It takes up less room and I don't have a bunch of batter cable connections to worry about cleaning. Also you cannot tell the batterys state of charge by voltage thats just a rough guide. The only real way to check the SOC is checking each cell with a hydrometer. And there is a lot less cells to check with one big battery. The one big problem with a forklift battery is that if one cell goes bad the whole thing goes bad. But a cell can be cut out and replaced. And they are built a lot more heavy duty and less likely to go bad and last longer. I have heard of then lasting 30+ years on a solar system.

   For the last four year we have been running a very used 24v 510 amp hr 1100lb forklift battery and 24v power inverter. With two 110w solar panels ad cheep charge controller just to keep the battery charged while we are not around. And we run off that 3 days or so then charge it with the generator. Which generally takes five hrs and 2 1/2 gal of diesel. 

   We just bought a new forklift batter from GB battery. 750 amp hrs 1500 lbs. And we are going to put up 10 230 solar panels we got from sunn elec. And yes it did take a while to get them. With a outback 80 amp MPPT controller. 

A small 12v forklift battery from GB is 450 amp hrs (670 at a 20 hr rate) 528 lbs and is $1309. The same power inverter I have but in 12v is $399. And the outback 60 amp MPPT controller is around $500. which comes to $2208 leaving you with $800 for solar panels. To which you could add more latter. 


http://gbindustrialbattery.com/Forklift_Battery_Sizes_and_Specifications_Zone15.html  GB battery price list

http://www.theinverterstore.com/the-inverter-store-product.php?model=pwrinv500012w power inverter. While you can go smaller the bigger ones just seem to work better and you always end up needing more power than you think.


Billy


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