Propane Generators

[peternap]

I have a couple of generators but the main ones are the diesel which is dependable, so heavy it has to be moved with the tractor and loud enough to wake the dead...and a small 4000 watt china special. I paid about 500.00 for it 6 or 7 years ago and it works well for small jobs, until it doesn't work.

I had a low tire on one of the ATV's today and the generator decided to not work again. I expect I need to rebuild the carburetor again.

Redover mentioned his propane generator the other day, which got me thinking. I think they are quieter, more dependable and run cooler for longer periods.

That's the extent of what I know and I expect some of that's wrong.

Any thoughts, experience, favorites?

[flyingvan]

   Just a few things---propane generators are great for applications where they may sit for awhile, as the fuel never goes stale.  You do have to be sure that whatever tank you're feeding it from has adequate liquid surface area to keep up with the demands of the generator, even on the coldest day your area can throw at you (There are nifty formulas for btu output/tank/temp but it's easier to just pick the brain of the local supplier)  Just don't count on a 20 lb. bbq tank to keep up with a bigger generator during a cold snap....
   With ANY LPG appliance, do not create a 'sump' situation, where propane can pool if there are leaks anywhere in the appliance or system.
    Also, the odorant in propane----methyl mercaptan, CH4S (A thiol, just like the scent a skunk makes, or what off gasses from roofing tar, or when you crack the lid of a gifted homebrew)  is kind of thick and oily and will settle and pool in old propane tanks.  It will also settle in low spots of distribution piping over time, so the ocasional drip leg off of a 'tee' is a good idea.  (If you're ever working on the piping in an old RV you may have encountered some concentrated mercaptan)  It's added so you can smell the gas, and the odor threshold is much, much lower than the flammability concentration, which is a good thing.  Just be aware if you ever spill even a little mercaptan out of old pipes, old tanks, or old drip legs---your neighbors will swear there's a huge gas leak somewhere.   It's hard to wash off too.
   Propane will run cooler, offer more power than natural gas, and if you ever rebuild the motor the piston will look brand spankin' new.  It's pretty pure stuff, especially compared to gasoline---burn a molecule of propane (C3H8) in the proper conditions and you get 3 CO2 molecules and you just created 4 new water molecules to boot---doing your part to help the drought relief effort.  (OK so you get a trace of sulfur hydroxide from burning the mercaptan but it's teeny) Products of combustion from gasoline and diesel would take a long time to list and I've lost every reader but you by now anyway.
   Finally---your propane will burn best (get the most work, bluest/hottest flame, produce the cleanest exhaust) if the fuel mixture is correct.  The generator you buy will be correct----at sea level.  You're OK until you get past about 2000', then it's worth changing the orifice size (You can just solder over the orifice and re-drill it if you can make accurate, small holes, or just buy a smaller orifice)  You decrease the orifice size by 4% for every 1000' over sea level you are.  You Leadvillains are looking at a 50% reduction in orifice size, but since your air is so darned thin it's necessary.

[Native_NM]

My brother has a Yamaha with the propane carb conversion.  He says it is the best purchase he's made for tailgating and hunting/camping.  It is very quiet.  Puts out enough power for weekend use.  Since he doesn't use it full-time, he was worried about ruining an expensive generator by leaving fuel in the tank.  He lives in Southern California and they have really cracked down on the generators at sporting events. 

[rick91351]

Hey Van you did not loose me and I read every word.  I am ready for the quiz   

Good info.....  Even had to confirm where the heck Leadville is at.  I said something to my wife about that and she says her Uncle Joe was a sheriff there.  The stuff I find out on CountryPlans     After all these years I did not even know she had a Uncle Joe   

[Redoverfarm]

Peternap the only real drawback on my propane generator is that it is not portable in a sense that you cannot drag it around from location to location.  I have two Generac's the one at the cabin being the smallest.  It is a 6KW.  The other is a 12KW at the house.  They do have the option of manuel or autostart.  Both of which need a powersource when not running to keep the starting battery (12V) charged up.  The house is not a problem in that I have grid power for that.  The cabin however uses the battery bank to maintain the charge. You could use a small solar panel to maintain the battery status though.  I am satisfied with both as they function as intended. 

I believe there are a few others on the market that have multifuel capabilities that might be more portable but with propane  lugging a propane tank around could be a problem.  Most will use 1.5-2.5 GPH of propane so using a small propane cylinder is a problem. 

The last I checked there is available a 8KW for about $1,900.  You will need something to transfer the power to as there is not external plug.  A transfer switch is about $400.  Of course in a manuel mode it can be wired to a panel box providing that there is not grid power or you have a way to disconnect grid power when running.

Generac only makes one generator that I am aware of that is warranteed for "off grid" function.  That is the 6KW EcoGen.  Others are meant to be "standby" meaning that they only run occassionally when grid power is out.  They void the warranty of those if used in an "off grid" function.

[peternap]

Thanks John. The portability is a very good point so I rebuilt the calibrator today. Running fine again...until the next time.

[Rob_O]

   With ANY LPG appliance, do not create a 'sump' situation, where propane can pool if there are leaks anywhere in the appliance or system.

Yeah, propane leaks can be bad

http://www.cnn.com/2012/08/14/us/new-york-home-explosion/index.html