OFF GRID POWER; various thoughts on...

Started by MountainDon, January 13, 2009, 02:18:39 AM

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MountainDon

Quote from: OlJarhead on August 08, 2013, 05:52:38 PM
.... an 8.5kw LP off grid genny set up just like the generac but not as quiet (65db vs 52db) that puts it about $600 less after shipping etc.

I have heard John's Generac run.
I have a generator that purportedly has a dB rating of 65 - 68.
I much prefer the quieter one; Generac with average half load dB of 52. That is much like a little Honda EU1000!
I place a premium on quiet; worth it to me.
Just because something has been done and has not failed, doesn't mean it is good design.

OlJarhead

Quote from: MountainDon on August 08, 2013, 06:01:40 PM
I have heard John's Generac run.
I have a generator that purportedly has a dB rating of 65 - 68.
I much prefer the quieter one; Generac with average half load dB of 52. That is much like a little Honda EU1000!
I place a premium on quiet; worth it to me.

Good point -- and something I've been thinking about too. 

I've used Generac before and it does have a good warranty (2000 hrs or 3 years) but seeing the price on the Kholer which is also a good name and being $600 cheaper for 8.5kw vs 6kw of the Generac and I have to wonder if it isn't just that much more worth looking at.

Guess I need to hear one run!


OlJarhead

Reviews seem to suggest folks are very happy with the Generac and the sound level is often described as Don does which makes me think for an off-grid unit it would be better.  I might ignore the $600 difference and go with it anyway.

OlJarhead

Next question:  what 24v to 12v converter do you use?  I see Samlex makes one (SDC-23 20 Amp 24v DC to 12v DC Converter) but I've also seen some very small ones out there too.

I'll need one to run 2 small 12vdc fans (120mm fans used for composting toilet vent and an insulated duct to draw air to same), a 12vdc ceiling fan and a car stereo.

Thanks!

MountainDon

see this link...   

Solar Converters was the brand. Not sure if they make them any more.

I chose bigger than needed and am glad as I since added another occasional use item.
Just because something has been done and has not failed, doesn't mean it is good design.


OlJarhead

Spendy little buggers  ???

I've sent a note out to two suppliers, one whom I deal with a lot and another I'm likely to deal with soon ;)

OlJarhead

Just read a review of the Kholer by someone who sells them and I have to say that it steered me RIGHT BACK to the Generac!

QuoteFor years we were able to offer the Kohler models that did everything listed above with great success. Unfortunatley Kohler (and all other manufacturers) have discontinued production of models that worked great for off grid use and have instead focused on making residential grid backup models that need 24/7 utility power to run the controller and only get used occasionally when the grid goes out. While the current Kohler models we offer are not ideal in some ways due to the high speed 3600RPM, two cylinder air cooled engine, continous power use even when off to run it's controller which will drain it's starting battery in less than a week if not accounted for and less efficient operation when running they DO have some very positive attributes. Two wire remote/auto start is standard, the sizes available are ideal for battery charging, LP fuel use, and they do have a warranty for off grid use. The Kohler 8.5RES and 14RES are very similar in price to a Honda 6500 but have a weatherproof enclosure, simple two wire auto start and LP fuel.

Looking at the Generac it runs at 2600RPM so a little lower, is much quieter and has a 3 Year/2000 Hour Limited Warranty (much better then Kholer).  Not sure how many watts the controller uses and it does have a 2.5amp trickle charger so that's 300watts which seems like a LOT (maybe it's me but a 300watt appliance running full time on a small off-grid solar power system seems a but much...what am I missing?

Anyway, I'm thinking the Generac is likely where I am going despite the $600 increase in price -- my wife would prefer the lower priced model but I just think we'll be happier with the Generac

ChuckinVa

I too have heard John's Generac run and inside the cabin you hardly can hear it. The company I work for sells Siemens generators which are Generac with a different label. They are now offering a 5 year warranty. It may not apply to the off grid model but worth looking into.
ChuckinVa
Authentic Appalachian American

OlJarhead

John Raab?  Or another John! lol  Wasn't sure who Don meant -- or is Redoverfarm also a John?

Looked at some options and decided that if I get the job we might not use cash for the genny since CC companies are begging us to get another card (we generally pay them off before interest is charged and then close them! lol they don't like that but keep offering it to us).  We figure since we'll be saving rent (if I took a job anywhere else I'd pay rent) the savings more then covers the cost of the generac.

One of my challenges now is to figure out how much propane I'll need.  I'll be running the genny quite a bit in the winter since the battery bank is a little small for what I want to do and then I'll also be running an 8000btu heater like MountainDon's to keep the composter room warm.  My thought there is to super insulate the room and the duct coming from the wood stove so that it won't require that much heat to keep above 50 degrees.  I plan to build with 2x6 walls but after reading (a long time ago) about CoyoteRidge (I think it was anyway) with his double 2x4 walls I'm thinking a 2x6 R21 outer wall with a 2x4 R13 inner wall and an R30 roof and well insulated dict from the wood stove pushing warm air into the compost room and I ought not to run the propane heater that much -- maybe only once or twice a nice/day.

So with that, plus an 18000 btu heater of the same kind inside the cabin to keep it warm when I'm not there, the genny, cook stove and instant on hot water and, well, I'm not sure if a 250 gallon tank will be enough.


Rob_O

Quote from: OlJarhead on August 10, 2013, 11:07:49 AM

is Redoverfarm also a John?


Yes

And that is a *huge* difference in SPL between those generators, the Kohler will "seem" to be more than twice as loud as the Generac and you will spend years regretting not spending the few bucks extra for the quieter model. As always YMMV
"Hey Y'all, watch this..."

considerations

Shopping is so much fun..its the installation that tests the ol body.

OlJarhead

Not power but I saw some solar hot water panels for $50 today on CL.

Gotta admit that $50 got my attention!  Wonder if I could use those?  Problem I see is that I don't want to run a pump to push the water up into them on the roof and while passive should work with gravity fed system that's above the panels I'm just not sure.

Perhaps I could run the hot water lines into the panels and then into the instant on HW heater and reduce how much propane I use making water hot? 

Anyone used these things?

OlJarhead

OK I'm fighting with this: 2000 watt inverter with 6000 watt surge and 30A charger or 4000 watt inverter with 12k surge and 50A charger?

I think the 4k Inverter would be better because it's bigger and when it comes to power it seems better to error on the side of caution but I'm not sure I'd need it as the biggest load I have now is a toaster I don't use and in the future will be a 1k or lower MW Oven.

Thoughts?

MountainDon

Quote from: OlJarhead on August 27, 2013, 09:46:31 AM
OK I'm fighting with this: 2000 watt inverter with 6000 watt surge and 30A charger or 4000 watt inverter with 12k surge and 50A charger?


Everything else being equal; depends.

One reason I went with 3500 watts was the experience of using inverter power in the RV. The inverter used was not large enough to permit simultaneous operation of some of appliances. So most of the time we are using just a fraction of the available inverter power. Perhaps not the most efficient inverter operation. ???  But using anything around the cabin requires no thought about what else might be on or what else might come on.

Depends on the user and user's family.
Just because something has been done and has not failed, doesn't mean it is good design.


OlJarhead

Thanks Don -- now another problem has cropped up:  Transfer Switch Ratings vs Generator power output???

I was told that the generator's 50A @ 120v was higher then the 30A transfer switch on the 2000 watt inverter and possibly more then the 4000 watt inverter.  A 6000 watt inverter charger has a 65A (waiting on final word) transfer switch and 85A charger but is really WELL over what I think I'd need.

Waiting on them to call me back.

OlJarhead

http://www.theinverterstore.com/4000-watt-pure-sine-inverter-charger-24-volt.html#
Got my answer :)  AIMS is FAST!

The Tech explained that their Transfer Switched are rated at 240v so no problem using the Generac 6kw with them but he recommended the 4000watt inverter primarily because it's capacity to charge the batteries and provide the full 4kw when hooked up to the generac.

he also agreed that the Magnum Auto Gen Start was the better way to go.

Redoverfarm

Eric not to steer you either way but I feel you will not regret going a little larger on the inverter.  Who knows what additions you will add in the future as far a electrical needs.  There are a couple things about my system (non solar) that I guess I need to toot my horn. Once I got the system set up correctly I just monitor things and it does the rest. 

Here is the outfit that worked my details and I ultimately bought from their company on my Magnum products.  Was the best price I had gotten and Kent Osterberg was super knowledgable.

http://www.bluemountainsolar.com/

Magnum support has been outstanding. 

This was sent to me by Bob Cramer one of the system designers/ Big Wig  at Generac.

"The drawings you are pulling off the web may be old and the wrong ones for the generators you are buying. The proper generator for off-grid living is the Generac EcoGen unit. It is designed for off-grid installations, comes with a 3 year warranty, has 500 hour service intervals, reduced noise, reduced fuel consumption and is 120v factory wire with the ability to be 240 converted.



With that being said, before we launched the EcoGen generator I had engineering incorporate a 2 wire start feature into the HSB 2008 and 2010 controller. One controller uses pin 17 and 18 and the other uses 21 and 22. The older 8kw and Core unit do not have 2 wire start capability so they cannot be used in this type of installation. When I get the serial number of the unit you are using I will send you the retrofit kit and you will be able to make the change. We record the serial number and match it with the registration information and not the system that the unit has NO warranty because of the application it is being used in."


The BMK in my opinion is the way to go.  Not only does it monitor the voltage it also monitors the SOC (State of Charge).  I have my AGS set to start both ways as a fail safe.  One just a tad lower than the other.

OlJarhead

Thanks.  The Magnum BMK battery monitor kit when I first looked at it I thought was for the Magnum's only.  Wasn't until after buying a Bogart Engineering Trimetric Battery Meter Kit that I realized the BMK was about the same thing.

That being said I've probably gone a little overboard as I ordered all of these:
Bogart Engineering Trimetric Battery Meter Kit
Remote Control for AIMS Power Low Frequency Inverters
ME-AGS-S Auto Gen Start
Solar Converters Step Down Voltage Converter - Model PPT12/24-20/R12
AIMS 4000 Watt 24 volt Low Frequency Inverter Charger

Now I'm about to order the Generac too :)

So I'll have remotes for the Inverter and the batteries as well as the Auto Gen Start and I might even order one for the MPPT Controller too ;)

Stick in a CD player and some speakers and I'll have one heck of an entertainment center! lol

MountainDon

#1143
I guess I'm too late for this question?
Do the AIMS inverter/chargers have a search mode? And what is the power draw in search?

Search can save a lot of battery power when nothing in the cabin is actually consuming power, but you want to be able to have something work the moment it is turned on. If there is no search function then the inverter has to be on and in idle mode.

I've seen some large inverters that draw up to 5 amps (at 24 VDC) when in idle; up to 2 amps in search..
Our Outback draws 20 watts (0.8 amps) in idle and only 6 watts (0.25 amp) when in search.   If the system has an Outback charge controller then the remote (Mate) can be used with both the CC and the inverter/charger.
Just because something has been done and has not failed, doesn't mean it is good design.

OlJarhead

QuoteIdle Consumption with Power Saver Mode ON: <1.88 amps DC depending on search mode
Quote
    4000 watt low frequency inverter
    12000 watt surge for 20 seconds 300% surge capability
    Terminal Block
    GFCI outlet
    Marine Coated and Protected
    Multi Stage Smart charger 40 Amp
    remote panel available
    auto frequency
    10msec typical transfer time
    optional 25W power save mode
    7 battery type settings for charger


OlJarhead

I wanted an outback or a magnum but honestly AIMS has treated me well and the cost savings over the others was enough to make me stay with them.

upa

Hi Folks

After a bit of an extended absence I am happy to be back on the forum.
I am looking to replace my rubbish Xantrex Freedom HF1800 watt inverter /charger. It worked great when it worked. Unfortunately it's only 3 years old and on a cold winter's night roughly 16 months ago the charger  shorted its board and now unfortunately the inverter portion for no apparent reason has stopped working all together.  Turns out these new inverters from Xantrex are china made, I guess I should not be surprised as its hard to find ones that are not.  After reading the last few pages of this thread  I have had a look the Aims inverter chargers as they sound attractive but after reading many of the online manuals they mostly appear to be made either in Korea or China. Now I have my fair share of Chinese consumer goods, which some have represented good buys but I am very leary about going down this road again. I have also heard suggestions from Midnite folks( may be former employee sour grapes) that although products like Outback are assembled in the USA its unclear if they don't source come their components from elsewhere. Soo, long story short I am looking for an off grid 3-4kw 48 volt low freq sine inverter setup. What manufacturers should I be looking at from a reliability perspective( i.e, I want more than 3 years service)? confused? I am sorry upfront if this stirs up some sort of ford vs chevy( or china vs the world :) debate, That truly is not my intention.

Thank you

Redoverfarm

Quote from: upa on August 28, 2013, 08:15:32 AM
Hi Folks

After a bit of an extended absence I am happy to be back on the forum.
I am looking to replace my rubbish Xantrex Freedom HF1800 watt inverter /charger. It worked great when it worked. Unfortunately it's only 3 years old and on a cold winter's night roughly 16 months ago the charger  shorted its board and now unfortunately the inverter portion for no apparent reason has stopped working all together.  Turns out these new inverters from Xantrex are china made, I guess I should not be surprised as its hard to find ones that are not.  After reading the last few pages of this thread  I have had a look the Aims inverter chargers as they sound attractive but after reading many of the online manuals they mostly appear to be made either in Korea or China. Now I have my fair share of Chinese consumer goods, which some have represented good buys but I am very leary about going down this road again. I have also heard suggestions from Midnite folks( may be former employee sour grapes) that although products like Outback are assembled in the USA its unclear if they don't source come their components from elsewhere. Soo, long story short I am looking for an off grid 3-4kw 48 volt low freq sine inverter setup. What manufacturers should I be looking at from a reliability perspective( i.e, I want more than 3 years service)? confused? I am sorry upfront if this stirs up some sort of ford vs chevy( or china vs the world :) debate, That truly is not my intention.

Thank you

Might check on previous post in this section.  As for me I have a 48 volt system and am satisfied with Magnum products.  Here is what I have.

http://countryplans.com/smf/index.php?topic=6059.msg172189#msg172189

MountainDon

#1148
Apollo, Magnum, Outback, Schneider/Xantrex XW series.

And if you have a charge controller by one of those it would be nice to have the same brand as usually you can then integrate the two with one remote.
Just because something has been done and has not failed, doesn't mean it is good design.

OlJarhead

Quote from: OlJarhead on August 27, 2013, 03:12:56 PM
I wanted an outback or a magnum but honestly AIMS has treated me well and the cost savings over the others was enough to make me stay with them.

To clarify this the Magnum I found in the same power output range was $2 vs the AIMS at $1.3k

That $700 difference was the cost of my concrete ;)