propane generator warranty for off-grid application

Hello,
For a whole-house energy system, I was searching for a heavy duty propane generator for off-grid application, and I was considering Kohler RS12000 due to its reliability...Much to my surprise that the warranty is not valid for off-grid application (in talking to a rep).

I've since started looking into other generators and their warranties, and I could not find a generator that would provide explicit warranty for off-grid application...

Does anyone know of a generator that would have a descent warranty for off-grid application?

Comments

  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: propane generator warranty for off-grid application

    actually i'm confused by this type of out for the generator companies for when one runs a generator is it not because there isn't any grid power? when the grid is around i certainly am not in the habit of using my generator and it does not tie into the grid. you should ask the companies just exactly when it is that they expect you to use it that it would be covered.
  • Vic
    Vic Solar Expert Posts: 3,208 ✭✭✭✭
    Re: propane generator warranty for off-grid application

    Hello Hawanam,

    Yes, this appears to be a recent change by Kohler ... unfortunate, but must be based upon their experience.

    There is a bit of a reference to this situation in this thread:
    http://forum.solar-electric.com/showthread.php?t=7462

    Think that, basically, air-cooled engine gensets are not really made for the duty-cycle that goes with most off-grid uses. AND, an 1800 RPM water-cooled genset usually begins at about the 18-20 KW range. Think that even at this level, Kohler still does not warrant off-grid uses -- none of their sub-25 KW/KVA units seem to be rated for Prime Power.

    If it needs to be LP, new, and under 20 KW, think that it will be a rough road for you. You can probably find an older, used genset which is water-cooled and 1800 RPM for a reasonable price, and should run for many additional hours, if it has not been beaten to death already.

    Generac may have something which in not excluded from off-grid use, but think that they have worked farily hard to sully their reputation in the smaller-sized units. No free luncheon. AND, as you prob know, a gensset sized considerably larger than your needs can waste a lotta fuel.

    Diesels, generally, are the heavy-duty solution, and many are very quiet, BUT there is the fuel deal. LP is very nice, especially if some company will deliver the fuel and keep you topped-off. LP has become very expensive on a BTU/$ basis, and seems prohibitive for many of we off-gridders.

    Not really a direct answer to your question, I know. Good Luck, and let us know what you find. Vic
    Off Grid - Two systems -- 4 SW+ 5548 Inverters, Surrette 4KS25 1280 AH X2@48V, 11.1 KW STC PV, 4X MidNite Classic 150 w/ WBjrs, Beta KID on S-530s, MX-60s, MN Bkrs/Boxes.  25 KVA Polyphase Kubota diesel,  Honda Eu6500isa,  Eu3000is-es, Eu2000,  Eu1000 gensets.  Thanks Wind-Sun for this great Forum.
  • Vic
    Vic Solar Expert Posts: 3,208 ✭✭✭✭
    Re: propane generator warranty for off-grid application

    And, Niel, was writing while U were posting.

    Think that the largest part of the market for NG/LP gensets is for home standby at on-grid homes. This is usually for infrequent, and shortish duration grid outages. Then the light-duty components are not over-taxed, and may rack up only 10-20 hours per year. This way the warranty runs out before 100 or so hours are racked up, at least typically.

    A neighbor burned up the air-cooled engine on a 12ish KW Generac in a couple of years, as he was running it for 4 or more hours per day for a couple of years. This is tough duty for the little engine and alternator.

    JMHO Vic
    Off Grid - Two systems -- 4 SW+ 5548 Inverters, Surrette 4KS25 1280 AH X2@48V, 11.1 KW STC PV, 4X MidNite Classic 150 w/ WBjrs, Beta KID on S-530s, MX-60s, MN Bkrs/Boxes.  25 KVA Polyphase Kubota diesel,  Honda Eu6500isa,  Eu3000is-es, Eu2000,  Eu1000 gensets.  Thanks Wind-Sun for this great Forum.
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: propane generator warranty for off-grid application

    vic,
    doesn't it stand to reason that if they feel it can't handle a long duty cycle that you shorten the time period that it is warranted for rather than throwing the whole warranty out the window with 1 giant loophole? how many of their generators are gt? oh but that's not what they meant. then why is it stated that way if that's not what they meant? i'm still confused as is the op. if they state no off grid then they better explain when it can be run and how it's to be run that they will honor their warranty. this is the equivalent of voiding a pv warranty for it getting hot from the sun.
  • Vic
    Vic Solar Expert Posts: 3,208 ✭✭✭✭
    Re: propane generator warranty for off-grid application

    OK, Niel,

    This is interesting reading FYI:

    http://www.boostyourliving.com/richpgenerators/TIB101.pdf

    The smallest Kohler LP Prime Power genset that I've seen in current production is 25 KW.

    I just went through the selection process for an LP Genset. It is getting more difficult to source a sub 18 Kw unit that is 1800 RPM and water-cooled (these were two of the primary selection criteria).

    Am not trying to be agrumentative. YMMV Have Fun, Vic
    Off Grid - Two systems -- 4 SW+ 5548 Inverters, Surrette 4KS25 1280 AH X2@48V, 11.1 KW STC PV, 4X MidNite Classic 150 w/ WBjrs, Beta KID on S-530s, MX-60s, MN Bkrs/Boxes.  25 KVA Polyphase Kubota diesel,  Honda Eu6500isa,  Eu3000is-es, Eu2000,  Eu1000 gensets.  Thanks Wind-Sun for this great Forum.
  • benjamin
    benjamin Solar Expert Posts: 34
    Re: propane generator warranty for off-grid application

    It's fairly easy to convert small engines, think lawnmower etc, to run on propane. It only requires a few simple carburettor modifications and a vacuum regulator. If you're up to building a generator yourself you could potentially save significant cash.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: propane generator warranty for off-grid application

    From a mechanical POV there's quite a difference between "duty cycle" and "total hours". You could put an incredible amount of cumulative time on an engine without exceeding its expected duty cycle at any time. It's simply a good idea to shut them off once in a while.

    If you look at the differences between an "industrial" engine and a "consumer" engine you'll see changes in bearing sizes, oil capacity, cooling capacity, operating RPM, et cetera. In short, the "industrial" version will produce less power for its size because it is not "pushed" so much. This means it can run for longer intervals with less strain on components. Think about a tractor engine: running full throttle all day long in a field full of dust. Would your car's engine stand up to that? Not for very long.

    I think Vic's got it right on the issue; when they say "off grid" they're talking about using it as a primary power source. Which leads to the question of how long do they think their gens will stand to run? As a back-up solar source it will probably only be two or three hours a day, and not every day. Any generator should be able to handle this.

    In fact, any generator ought to be able to run constantly for one tank of fuel. Otherwise, why did they make the fuel tank that size? As a back-up for solar, I wouldn't worry about the warranty/run time of any gen except the really cheap ones which sound like they're coming apart the minute you start them!
  • icarus
    icarus Solar Expert Posts: 5,436 ✭✭✭✭
    Re: propane generator warranty for off-grid application

    I would talk to Kohler Corporate and have them define "off grid"! I think 'Coot has it dialed. An of grid application where the gennie is providing in essence 24/2 power would certainly be considered commercial/industrial duty. The same genny providing back up service to a PV system, might see 24 hours a week duty. Hardly the same application.

    While most stand by rigs may be industrial rated running 24/7 is not what they are designed for. That's ~8000 hours/year. Where as a 24 hour a week load would be ~1250 hours.

    Tony

    Ps My lister SL@ diesel will run 8000 hours/year without breaking a sweat at load, but my Honda EU 1000 probably won't run 8000 hours in it's entire life.

    T
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: propane generator warranty for off-grid application
    icarus wrote: »
    Ps My lister SL@ diesel will run 8000 hours/year without breaking a sweat at load, but my Honda EU 1000 probably won't run 8000 hours in it's entire life.

    T

    Don't bet on it: my Honda 1000 is getting pretty darn close to 8000 hours! :D
  • solar_dave
    solar_dave Solar Expert Posts: 2,397 ✭✭✭✭
    Re: propane generator warranty for off-grid application
    Don't bet on it: my Honda 1000 is getting pretty darn close to 8000 hours! :D

    You are now tempting the breakage gremlins! ;)
  • icarus
    icarus Solar Expert Posts: 5,436 ✭✭✭✭
    Re: propane generator warranty for off-grid application

    Marc,

    At 1/2 hour a month,, I ain't going to live that long!

    T.
  • Vic
    Vic Solar Expert Posts: 3,208 ✭✭✭✭
    Re: propane generator warranty for off-grid application

    For those who have not carefully read the link provided in the previous post. Kohler defines Stand By Rated gensets as those served by " a reliable utility source" . Exceeding the max rating of the genset is "prohibited". Typical run-time per year is 200 hours, except KM powered units = 100 hours, and the Waukesha units at 3500 hrs. For all other other durations, use the Prime Power rating, for which the smaller Kohler gensets ARE NOT RATED.

    For gensets with Prime Power ratings, it is permissible to use them for applications "where utility power is unreliable or unavailable"

    Am only speaking of what Kohler has written in the TIB-101 document linked previously. This doc. dates from January 2007, so it has been the definition for some time. Think that Kohler is just trying to be more specific when saying that certain models -- typically the smaller units, are not warranteed for "Off-Grid use".

    And in looking at the sub 150 KW units from Cat, Kohler, Onal-Cummins etc, all of the LP/NG models use current production automotive engines, usually Ford. So in these units, the old day Industrial engines seem to be absent. The Kohler LP that I recently snagged uses a Ford engine, with all the modern stuff (too bad), Crank position sensor, one coil per cyl, Ignition processor etc. Am not looking foreward to a failure in the Ignition system, bet the coils/processor are about $1.5 K+.

    Just trying to flesh out the obvious (to me at least).

    Off to the mountains. Spring has sprung ! Vic
    Off Grid - Two systems -- 4 SW+ 5548 Inverters, Surrette 4KS25 1280 AH X2@48V, 11.1 KW STC PV, 4X MidNite Classic 150 w/ WBjrs, Beta KID on S-530s, MX-60s, MN Bkrs/Boxes.  25 KVA Polyphase Kubota diesel,  Honda Eu6500isa,  Eu3000is-es, Eu2000,  Eu1000 gensets.  Thanks Wind-Sun for this great Forum.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: propane generator warranty for off-grid application
    icarus wrote: »
    Marc,

    At 1/2 hour a month,, I ain't going to live that long!

    T.

    Mine started life as a primary power source; got used 8 hours a day, 7 days a week, for six months stretch two years in a row. Sort of gave it a head-start on hours! Then it got used to recharge batteries for two months while I waited for one stupid component of the solar to show up. Now it has an easy life of running the occasional power tool, although it was pressed into service last fall recharging again as I needed the 2000 to run the block heater on the borrowed diesel truck. But it's over 6000 hours already, and not been rebuilt. :D
  • chevenstein
    chevenstein Solar Expert Posts: 100 ✭✭
    Re: propane generator warranty for off-grid application

    I believe that this has to do with liability on the part of the manufacturer. I'm not sure whether or not there's a specific UL listing difference between residential standby, commercial standby, and prime applications (which off grid is considered, even if the genset is backing up an alternative energy source), but generally speaking the manufacturer doesn't want losses attributable to the failure of one of their low end units to stand in the context of an off grid application.

    In a residential backup scenario where reliable grid power is available the backup genset is a luxury.

    In a commercial backup scenario where reliable grid power is available the backup genset may be required by code and its performance could be integral in the operation of a building's safety systems in the event of a grid failure. Consider an office building with an area that's wheelchair accessible only via a motorized lift or elevator. Say someone in a wheelchair is in this area when utility power fails and the building catches on fire. They're now trapped if the genset fails.

    In an off grid or other prime application the genset's operation is critical to the reliability of the electrical supply, whether the system is backing up RE or not. Legally speaking I'm not sure why exactly this is but it is the case. Practically speaking, I live off grid and use a cheap-junk LP genset for backup because it was free, but every time I run the thing I half expect it to either not start or die running. (I've already had a series of no-starts due to the starting battery charging circuit failing and a series of as yet unidentified sudden shut downs).
  • Mangas
    Mangas Solar Expert Posts: 547 ✭✭✭✭
    Re: propane generator warranty for off-grid application

    I have a high end 1800 rpm 15 kw propane unit.

    I challenged the manufacturer's position on this point in a recent letter. They didn't bother to respond.

    Their term "primary source" generating power was the issue. For my off grid use the genset is used only for battery charging during peak periods. It's not a primary power generation unit but a standby battery charger.

    I guess a modern sophisticated genset used for battery charging is beyond its capabilities.

    "Warranties" don't mean much anymore even when they're printed on the box. . . .
    Ranch Off Grid System & Custom Home: 2 x pair stacked Schneider XW 5548+ Plus inverters (4), 2 x Schneider MPPT 80-600 Charge Controllers, 2 Xanbus AGS Generator Start and Air Extraction System Controllers, 64 Trojan L16 REB 6v 375 AH Flooded Cel Batteries w/Water Miser Caps, 44 x 185 Sharp Solar Panels, Cummins Onan RS20 KW Propane Water Cooled Genset, ICF Custom House Construction, all appliances, Central A/C, 2 x High Efficiency Variable Speed three ton Central A/C 220v compressors, 2 x Propane furnaces, 2 x Variable Speed Air Handlers, 2 x HD WiFi HVAC Zoned System Controllers