Home Generators - Kohler?

[K6IC]

That's a good summary Bill.

Diesel has more than 40% more BTU content than Propane.  And  seems that the Diesel gensets have  much better fuel economy at lighter loads compared to gasoline/Propane fueled engines.  IIRC,  my Diesel genset burns 1.8 GHP at full load,  and 1.0 GPH at half load ... not a bad ratio.

Energy content table:
http://www.generatorjoe.net/html/energy.html

Here the grid power has become much less reliable,  so many,  many more folks are buying generators.   Seems kinna wasteful.

72  GL  Vic

[Bill, KD0HG]

FWIW, you can burn JET-A or JP-4 fuel in a standard diesel engine. A favorite trick in airport ground equipment. It's good down to extremely cold temps without any heating.

[W3SLK]

Well, then that solves that. It probably makes more sense since I have a larger supply of fuel oil VS. propane.

Mike asked:

[What is an "elevated 9/11 HAZMAT fee" all about?

Its about a $35 fee added to the cost of using a 100 lbs. propane tank. It has been replaced by 2-25lbs jobs. When I asked about it, the propane co. told me that after 9/11 they HAD to assess a HAZMAT fee on them. Personally I think its all hooey and just a way to make more deliveries to me.

Bill asked:

How about a wood-fired steam engine?

Probably because you don't want to turn your back on a steam boiler. I bet a neat little verticle steam turbine would work awesome but you would have to 'ride it' or have some fancy computer program to stay on top of it and I don't like the consequences if it gets away from a computer.

[W3SLK]

Bill said:

FWIW, you can burn JET-A or JP-4 fuel in a standard diesel engine.

Yep. Pretty much nothing more than "polished" kerosene. If it gets into your water, you don't need any conditione when washing your hair. It makes it nice and soft. I remembered that when I had hair. 

[Mike/W8BAC]

http://www.beamalarm.com/foretravel-links/PDF/Racor_300200_pre_fuel_filter-48027%20Rev%20B%20(OBSOLETE)%20Integrated%20Series.pdf

Mike, This product might be perfect for your installation. Mounted close to the engine this will filter the fuel, separate water AND purge any air in the line. Air in a fuel line can cause the injector pump to cavitate and can ruin your day. Newer fuel injection systems use a much improved fuel delivery system and air isn't a big deal. Older technology mechanical fuel injection is the norm for gen sets and other stationary diesel engines. Air in a fuel line for mechanical diesel fuel injection means put the food in a snow bank and get out the blankets.    Some sort of check valve in the basement to keep the fuel in the line might be a good idea and extra care to make sure you have the fuel line sealed tight is just good practice.

I would pick the FR or MFR model. Scroll down for an installation schematic.

Mike

[KF1Z]

Mike asked:

[What is an "elevated 9/11 HAZMAT fee" all about?

Its about a $35 fee added to the cost of using a 100 lbs. propane tank. It has been replaced by 2-25lbs jobs. When I asked about it, the propane co. told me that after 9/11 they HAD to assess a HAZMAT fee on them. Personally I think its all hooey and just a way to make more deliveries to me.

$35.00 per  "what" ?

I have a 300 gallon tank, and unless they have rolled the fee into the cost of fuel, they haven't charged me extra since 9/11

Or does this only apply to the little 100lb tanks?

[W3SLK]

I was hoping to find it on their website but it did apply to my 100lbs. tank. They wanted a real obnoxious price for it vs. 2 of the 25lbs cylinders. Like I said earlier, I think it was a way to charge me more for delivery rather than me buy in greater quantity at a lower rate.

[The Slab Bacon]

Downside is that #2 diesel fuel can have a limited storage life. It can support algae growth if even a small amount of water is present. You need to add a diesel biocide to the tank if it is stored for years.

Bill,
     Adding the diesel biocide is a good idea, but I really question it's necessity. My tractor is still running on diesel fuel that is somewhere close to 25 years old. It DOES have the black algae growing in it, but my dual fuel filters are keeping it out of the injection pump. The fuel has a very perculiar smell in the tank, but the exhaust smells like any normal diesel engine running on #2. And it starts just fine with it.

If you are using a diesel genset fueled off of your heating oil tank, that will never be a problem as the fuel will never set that long. The biggest problem using your heating oil tank is the sludge and debris that accumulates in the bottom of the tank. For some reason fuel oil seems to have a tremendous amount of gunk and debris mixed with it. You MUST have a good filtering system to keep it out of the injection pump.

[Mike/W8BAC]

Slab,

I wonder if the "gunk and debris mixed with it" is the algae itself?

Mike

[K6IC]

A severe algae infection can result in a fuel tank full of "snot".   This snotty algae can plug filters.  But,  it is correct that the algae requires the presence of water.

Keeping the fuel tamk topped off helps reduce water infiltration.

I use a fairly heavy dose of the biocide in diesel fuel as insurance.

Vic

[WQ9E]

I used to buy red dye fuel for the utility tractor but I use so little mowing 5 acres and moving snow that it wasn't worth running 20 miles to the farm co-op to buy it.

The biggest gel problem now with diesel is the amount of bio (from Soy) that gets mixed in since it has a much higher gel point.  I assume they aren't doing that to home heating oil yet.

With modern HPCR (high pressure common rail) injection systems diesel lubricity is a major concern so I wouldn't want to try any of the jet fuel varieties without the manufacturers consent.  With home heating oil I would add one of the various lubricity enhancers just to be safe.  Although soy oil creates a problem with gelling it is a great lubricity enhancer.

I have only had one gelling experience in a pickup and that was enough.  It was in my '95 after I foolishly bought some diesel from a nearby station because it was convenient.  After running about 30 minutes in -24 (actual temp) conditions I stalled and had to change filters to make it to a store and add some anti-gel.  My current pickup has a heater in the fuel filter assembly but I still keep a spare and tools handy just in case.  With a generator you could easily put a wrap of heat tape around the filter since this is the choke/trouble spot from waxing/gelling.

The nicest part of having a generator is not having to sweat the ice storm forecasts!

[WA3VJB]

The gasohol being sold in many states is nasty to carburetors. I have found it corrodes needle and float valves- eventually- if they're not drained before long-term storage. (Yes, I now know how to rebuild Briggs and Stratton carburetors- LOL). A gasoline additive is "Sta-Bil" which is supposed to preserve gasoline and prevent gumming. I use it in my own 7.5 KW standby Kohler.

OH yeah, the methanol at 10% is nasty against the boat engines around here, and there's huge stink in the works as Agri-business lobbyists try to get the feds to push it up to 15%.

Sta-Bil has worked pretty well for me in both the regular and high-test versions, used in the 1969 Datsun roadster and the 1964 Buick Electramobile that sit here for months without being out for a drive.

I just got a $20 bottle of the "marine" grade StaBil to handle the 40 gallon capacity of the boat now that it is put up for the winter. The reviews suggest it keeps the methanol/water content from separating, causing stratificaiton where the water sinks to the bottom right where the pickup pipe is.

[KD6VXI]

Diesel: downside is cold weather/ fuel gelling up
Gasoline: downside is fuel gets stale
Propane: downside is delivery by supplier


I understand the hot ticket is to get propane with adjustable jets and fuel switchover with connections for external LP Gas canisters like for outside BBQ grills.  Lets you bridge if the delivery truck can't get there for a while, like in our snows here last winter.

Here on the west coast, it's the law.  The lead that comes OUT of your regulator on the tank is the EXACT SAME SIZE as the BBQ propane tanks.

I've kept my kids warm for 3-4 days at a time.  10 gallons a day, making a trip down the mountain every day.  For some reason, the 4 companies that service my area don't feel 4x4 trucks would pay off.  Of course, the owner of the largest lives at the TOP of the mountain, but he has FOUR propane tanks on his property

One xmas, we lost power AND had no propane.  I think that's the Christmas I'll forever remember, bar-b-queing hamburgers over our fireplace with my 4 and 5 year old......  It was a COLD and icy Christmas, but the memories will remain.

--Shane
KD6VXI

[W4EWH]

I design quite a few large generator systems, and every now and then a small residential system.

OH MY GHOD A REAL EXPERT! PLEASE HELP! 

Kohler is a good generator and they make a good residential option. I have always considered them slightly behind Cat and Cummings but not far. They are way ahead of the Generac and similar generators.

Now, here's my situation:

• 1700 Sq. Foot ranch house near Boston
• Natural Gas heat and hot water
• Electric pumps for heating system (Forced hot water)
• A couple of through-the-wall AC units, used only in summer
• An electric range for cooking
• Modest Ham Radio setup; roughly 2kw consumption
• No solar, battery, wind, water, or geothermal capability
• Power outages two to four times per heating season

Here's what I need to know, and would greatly appreciate your expertise on:

• What are the trade-offs between "Home Depot" generators and Kohler or other commercial-grade models? Would you recommend Coleman/Generac/etc. sets -
  
  • Never?
  • For emergency use?
  • As a reliable source for use two to four times per year?
• What about the mid-level generators like Honda? (My brother, W3TDH, swears by the Honda sets because the inverter produces "cleaner" AC). Is shopping in between "consumer" and "commercial" tiers a reasonable price/performance compromise?
• Is installing a diesel set worth the extra cost for a tank, lines, etc.?
• Are there options other than a backup generator? Can I get by with battery inverters or similar standby systems? Are they cost-effective compared with a generator?

Let me thank you in advance for your help.

73,

Bill, W1AC

[K6IC]

AC  Bill,

Even if your outages last days,  batteeries/Inverters do NOT make sense.  The Kohler mentiond is a residential unit,  not really Commercial/industrial.  Residential units are probably fine for most home back-up uses,  unless the outages are extended,  and the power denands are high.

You might want to have a small porpane camp stove for cooking during outages,  as the electric stove is a large load.  A BBQ should also suffice.

Regarding small tanks and Propane (LP) gensets:  Usually LP generators are fed from Vapor.  The LP is evaporated at the tank.   In very cold WX or with a small tank,  the tank can freeze.  This chokes off the Propane supply.  Perhaps in the NE and other COLD climates,  the LP is fed as a liquid to the genset,  where there is an evaporator.   BUT,  usually these evaps are warmed by cooling water from a water cooled engine powering the genset.  There must be an electrically-heated evap for you folks in COLD climates,  as most reasonably sized gensets are now driven by air-cooled engines.   Here,  I have no experience.

It is COLD here in CA now --  Its 46 degrees outside!

YMMV   GL    Vic

[W3SLK]

Paul said:

The reviews suggest it keeps the methanol/water content from separating, causing stratificaiton where the water sinks to the bottom right where the pickup pipe is.

Well, then you do what they do at work: You make a cut! Drain the water until you get past the "rag" or emulsification layer and voila......no more water. Just don't shake it up.

[Bill, KD0HG]

Regarding small tanks and Propane (LP) gensets:  Usually LP generators are fed from Vapor.  The LP is evaporated at the tank.   In very cold WX or with a small tank,  the tank can freeze.  This chokes off the Propane supply.  Perhaps in the NE and other COLD climates,  the LP is fed as a liquid to the genset,  where there is an evaporator.   BUT,  usually these evaps are warmed by cooling water from a water cooled engine powering the genset.  There must be an electrically-heated evap for you folks in COLD climates,  as most reasonably sized gensets are now driven by air-cooled engines.   Here,  I have no experience.

It is COLD here in CA now --  Its 46 degrees outside!

YMMV   GL    Vic

Funny you mention that, I recently had to get two different service guys out to fix a Kohler 80 KW liquid-feed propane generator. Powered by a turbocharged Ford 460 V8. The problem was that the speed would surge out of control when it first started, causing an automatic overspeed shutdown.

The first guy dinked with the electronics and governor and gave up.

The second guy figured out the problem- The engine's block heater had failed. The propane wouldn't gasify in a cold engine and just stayed liquid at what, -40F, into the engine. Just like flooding the carb on a gasoline job. Even when the ambient temperature was in the 70s or 80s, it flat wouldn't run properly.

So in reality, liquid propane generators need block and fuel heaters as much as diesels do. Maybe even more so.

We had originally bought a propane set because we felt they might be easier starting than diesels in extremely cold mountain locations, but it ain't so. Diesel or propane, your block heater better be functional.

The only other advantage to propane was that you don't need some sort of a containment structure as needed in the event of a leaking diesel or gasoline fuel tank.

[W3SLK]

Bill said:

We had originally bought a propane set because we felt they might be easier starting than diesels in extremely cold mountain locations, but it ain't so. Diesel or propane, your block heater better be functional.

The newer glow plugs only require a few seconds and you are fired up and back on line. I thought it was Ford that said they would come out and start your Power Stroke Diesel if it failed to light off. 

[The Slab Bacon]

Slab,

I wonder if the "gunk and debris mixed with it" is the algae itself?

Mike

Mike,
       It was just the trash that they failed to filter out of it. You could run some fresh #2 out of the tank truck into a cup and see minute traces of black junk at the bottom.
Part of it may just be sloppy handling of the product by the suppliers as they use the same tank trucks to haul and deliver other products like "bunker oil" and back haul used waste oil. I used to work for a company back in the 70s that did that. I was hired as the truck mechanic, but I wasnt going to crawl into every trailer and steam it out between loads. The #2 we hauled would "wash" the tanks clean for us.    

[N4LTA]

Personal Message (Offline)
   
   
Re: Home Generators - Kohler?
« Reply #38 on: Yesterday at 11:59:24 AM »
   Reply with quoteQuote
Quote from: N4LTA on November 24, 2010, 06:18:34 PM
I design quite a few large generator systems, and every now and then a small residential system.

OH MY GHOD A REAL EXPERT! PLEASE HELP!  Wink

Quote from: N4LTA on November 24, 2010, 06:18:34 PM
Kohler is a good generator and they make a good residential option. I have always considered them slightly behind Cat and Cummings but not far. They are way ahead of the Generac and similar generators.

Now, here's my situation:

    * 1700 Sq. Foot ranch house near Boston
    * Natural Gas heat and hot water
    * Electric pumps for heating system (Forced hot water)
    * A couple of through-the-wall AC units, used only in summer
    * An electric range for cooking
    * Modest Ham Radio setup; roughly 2kw consumption
    * No solar, battery, wind, water, or geothermal capability
    * Power outages two to four times per heating season


Here's what I need to know, and would greatly appreciate your expertise on:

    * What are the trade-offs between "Home Depot" generators and Kohler or other commercial-grade models? Would you recommend Coleman/Generac/etc. sets -
          o Never?
          o For emergency use?
          o As a reliable source for use two to four times per year?

The Kohler is a better set than the Home Depot specials.  They are more reliable and tend to start when you need them.  I myself have a Coleman that I use for offsite things and when an ice storm shuts off power. If you let it sit unused though, it will likely not start when you need it. Last time I needed it to loan to a friend - it would not start - cost $75 to get it repaired (gunk in carb)


    * What about the mid-level generators like Honda? (My brother, W3TDH, swears by the Honda sets because the inverter produces "cleaner" AC). Is shopping in between "consumer" and "commercial" tiers a reasonable price/performance compromise?

The small Hondas are very nice and quiet. I am not familiar with the larger ones - but Honda makes a very good engine. Commercial sets are very expensive (compared to home sets) and are usually three phase. Three phase  generators are a better option for waveform purity.

    * Is installing a diesel set worth the extra cost for a tank, lines, etc.?

Yes - if you want to run for long periods and have motor starting loads.


    * Are there options other than a backup generator? Can I get by with battery inverters or similar standby systems? Are they cost-effective compared with a generator?

Not if you have a load of any size and you need to have backup for periods longer than a few hours. We typically install an inverter system with a gen-set backup for seamless transfer with no momentary loss of power. We do this generally for data and computer installations.

Pat

[W1UJR]

Met with the electrician today, discussed the project.
Need to trench about 5 feet, run two cables in conduit out of the house to the generator, install the transfer switch inside, build a plywood panel to hang switch, change over wiring.

Does $1850 for the above work sound high?

[N4LTA]

Probably not. It sounds a little high to me - but lately  - everything sounds high to me. My son is a contractor and he just got a price for wiring a new garage from three electrical contractors. It was $7200 for the low bid - which sounds real high to me.

I am a licensed electrical contractor also and it makes me wonder if  engineering is the wrong business for me.

[KB2WIG]

"  Does $1850 for the above work sound high? "

Is this just the labor, or does it also include the transfer switch/ cu/conduit etc?

klc

[Bill, KD0HG]

If that price includes the copper, that's a bargain, that's got to just be labor.
Although you could size up and use aluminum, even that's not cheap any more.
No way could the transfer switch be included.

[W1UJR]

Sorry, should have been clearer!

$1850 was for the electrical work, not the genset or xfer switch.

Interesting story today, had another electrician come over for a check, here is what he told me:

- 7,200 volts runs into my breaker box, I asked if he meant 240, he said no, 7,200 run from the meter to my breaker box

- The 200 amp breaker on my box protects the wire between the meter and the breaker box, not the panel and circuits after it, in fact we need to install another one to "protect" the power cable between the meter and the transfer switch

- That the resettable circuit breakers on my smaller manual generator transfer panel are "fuses", not circuit breakers

- They would have to install a sub-panel with a new set of breakers because the transfer switch is not designed to switch over the whole house, this despite Kohler clearly states and shows that in their design info

Needless to say that I called back electrician #1 and asked him to handle the job.