Portable Home Generator Questions

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After last month's ice storm in North Carolina, I have decided to invest in a portable generator. After some research at various sites, I am certain that around 8 kw will fit my needs. However, I still have **many** very basic questions about generator types, fuel storage, fuel consumption, power cabling to the transfer switch, etc.
I know there are a lot of questions, and hopefully folks will comment or advise on the ones about which they have knowledge or experience.
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In terms of efficiency and fuel use, which generator type is best..... gas, diesel, or propane ?
Has anyone here used a tri-fuel generator, such as the one made by Northern Industrial Tools ?
How can one safely and properly store 150 gallons of gas ? I figure this is the maximum amount that i would need in any severe storm. I am aware of the use of Stabil, and I would also "rotate" the gas at least once a year.
Has anyone here used a propane generator ? If so, how well did you like it ? What model have you used ? If you have not used one, do you know of one on the market right now, in the 8 KW range ? (I find that all the propane ones I find are much larger generators, up to 12-15 kw or higher).
In terms of fuel usage, is a gallon of propane about the same as a gallon of gas ?
I need 6 120 volt circuits, and two 240 circuits. The 240 circuits are needed for hot water, and water pump. Will this mean that I will need 3 distinct power cables run from my generator to the transfer switch in the house ? Are these pre-manufactured cables in given lengths, or will my electrician custom make cables ??
If I use a propane tank, it may well be 50 feet lower in elevation than my generator, and up to 100 feet away. Will the propane travel an uphill run like this ?
What is your favorite generator in the 7-8 KW range ?
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Well, that should be enough questions for now !!
Thank you in advance for any comment or advice !!
James
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As far as the transfer switch and cord, the units generally come with twist lok outlets up to 50 amps. You can buy these pre built, or built to whatever length you like. You typically run one cord from the generator to a manual transfer switch
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RBM, thank you for the good comments !! I am looking for a portable generator, as the is the price class that I am in. I will have a transfer switch installed by a qualified electrician, but it will not be automatically engaged. If we lost power, I will start the generator and flip the transfer switch.
As to the power cord, I am confused......... on the units I have seen, they have one or more 120 volt outlets, and most have one or two 240 volt outlets..... I would not need cords for each of these outlets ??
Very good comments/comparisons of gas, diesel, and propane.
Thanks again !!
James
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On the larger portable units they'll typically have multiple outlets. Some standard 120 volt 20 amp, some 120/240 volt 30 amp, and in your case you'd want one that has a 120/240 volt 50 amp. You would buy a transfer switch that would be fed through a 50 amp 4 wire cord, providing both 120 volt and 240 volts to the switch. There is no need to use any additional cords.
Another thing to note: portable units typically have fairly small fuel tanks, often holding less fuel than you'd need to go through the night. Check the fuel consumption at full load and at half load, then do a calculation to determine if it's big enough for your needs. You can always use a fuel tank, not attached to the unit, but it becomes less portable, and potentially more dangerous.

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Thanks again to all/ good site Dennis/ good comments CY.
James
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No, in a semi-pernanent installation you will have something like this next to your main breaker panel
http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_200321033_200321033
you only need one big 240VAC cord to make this work. sized for the total load that will be on the generator.
nate
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The transfer switch that Nate links to is probably the cheapest, easiest method of connecting a generator to your electric service, and won't take an electrician more than an hour to connect. Note: the one shown has a thirty amp twist lok

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When you have a transfer switch installed, you run one cable to the generator. It will usually have 4 wires in it and they will all go into the 240 volt plug. The older unit will have a 3 wire plug. Two of the wires will be to the hot wires, one to the neutral, and the other one if used will be a chassies ground. The power will be split as needed at the box at the house.
Diesel will probably be the best. It lasts for many years unlike gas. Also you will probably want to run the generator for short periods of time every couple of weeks or so. Gas tends to wash the oil from the piston rings and get into the crankcase oil during the short run periods.
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On Fri, 22 Jan 2010 19:23:36 -0500, "Stormin Mormon"
It can happen, if the engine is not allowed to fully warm up during the test runs. Diesels can also 'cold stack' if run without a load for an extended period of time. (some are more prone to doing this than others, but generally any emergency generator should be run under load when exercising it, to ensure that the entire system works properly).
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On Fri, 22 Jan 2010 19:23:36 -0500, "Stormin Mormon"
Particularly true of engines that do not get up to full operating temperature.
Propane, being a "dry gas" does not have this problem. Nor does CNG.
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On Sat, 23 Jan 2010 16:37:38 -0500, snipped-for-privacy@snyder.on.ca wrote:

Diesel engines are so efficient that at unloaded idle they barely get warm. I've got engines that you can touch the exhaust manifold if they have only been idling, even 10 minutes after starting. (pretty amazing).

True...
Best fix is simply to make sure the generator is loaded during exercising runs. The rule that I have is the run is 45 minutes, 15 minutes pre-online to get warmed up some, and to allow checking of everything, then 30 minutes full load (or as close as I can get to full load). Then a proper shutdown, and I'm set for the next exercise run (or next power failure!)
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If you have Propane or Ng get a Tri fuel unit, gas goes bad and filling it and storage is a pain. a 3600 rpm gas unit of Honda motor quality is worth maybe 2-4000 hours, cheap motors you get much less life, the cheapest around 300 hours. How you load it will determine alot of its life. 10 days running full will wear out some units, the biggest life increase is low rpm 1800 and lower but those are alot more money commercial units.
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On 1/22/2010 3:22 PM, James wrote:

I have an inexpensive PowerBoss from HD with running watts of 5500 and starting 7350. Transfer box, as others point out, requires only one 240 plug and will power my furnace, well, refrigerator, 2 small freezers and some left over for some TV and lights. Big items like AC, electric stove and hot water heater were left off circuit. Unit is noisy but less than half price of a Honda but in the 4 years I've had it, it's probably been run less than 50 hours. I store the unit full with two 5 gal cans of standby gas. You don't need to run the generator full time, like when you are out of the house or asleep. Living in a state like Florida where gas stations may be out too, then you need to store a lot of gas but not here in Delaware. Guess it depends on where you are in NC.
If we had gas, a gas generator would probably be preferred as it would be cleaner and maybe get by with less frequent start-up intervals.
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snipped-for-privacy@nospamfdn.com says...

Here is a site with excellent comparisons of different fuels:
http://www.nooutage.com/fuels.htm
--
Dennis


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## See imbedded comments
James wrote:

## Money is easier to store than gasoline. Hurricane Yikes made a believer out of us regarding sufficient fuel on hand (every gas station for 60 miles was without power to pump fuel). We now have oodles of gas cans and plan, when the forecast is for bad weather (hurricanes for us, ice storms for you), to get them filled in advance of the storm. We figure, after the storm passes, we can use the gasoline for our vehicles.
## If you go for propane or diesel, you'll have to muster a different strategy.
## If your generator uses one gallon per hour of gasoline, I'd think 50 gallons would be sufficient. First, you won't be using the generator 24/7 - there will be times - like when you're sleeping - you'll shut it down or you can have 'roaming blackouts,' two hours on, one hour off, or other rationing techniques. Second, when you get down to your last five or six gallons, you can forage for more fuel.

## The number of circuits and so forth is handled by your transfer switch; there will be ONE cable from the generator to your distribution panel. You can have a cable custom made, but cables do come in standard lengths (10', 25', 50', etc.). They ain't cheap!
## The 120v outlets on the generator are for use at a construction site or similar where there is NO distribution panel. The builders plug their saws and compressors directly into the generator. For emergency power, as in your situation, these outlets on the generator are typically not used.
## Footnotes: 1. Plan on some method of anchoring your generator against theft. 2. A couple of 100' extension cords are nice so you can accommodate your neighbor's minimal electrical needs (refrigerator, TV,...). 3. Generators are generally louder than the hinges on the gates of Hell. If you DO pay a premium for a quiet one, its only advantage is that you can better hear your neighbors' loud generators. 4. In these difficult financial times, I see several ads for generators on Craigslist at substantial savings. People seemingly are turning their seldom used assets into cash. You might find a bargain. 5. You can dispense with the transfer switch by adding a double 50-amp circuit breaker to your panel and wiring it to an external plug. If you do this, you'll need an interlock (Google for) to fit your panel. The interlock switch prevents the mains to the pole from being energized by your generator.
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HeyBub, your comments are very very helpful and informative. Many thanks !!
James
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I have always wondered why states (especially those prone to hurricanes, storms, snow storms) do not require that ALL gas stations have a simple backup generator so they can pump the gas that is in their tanks. And, of course, once the generator is started they can use their own gas pumps to keep filling their generator gas tank to keep it running.
I always think how stupid it is in a natural disaster emergency that people who need to evacuate can't get gas because the gas at the gas stations is unavailable simply because the gas station doesn't have the power to pump its own gas.
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Not only that but they dont make any money when they have no power.
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ransley wrote:

Most stations here in South Fl. have added there own generators. They learned a lesson after the 3 big ones a few years ago. I still have 40 gals. locked in my shed.
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Chuck wrote:

You are rotating your stock, right? Even in brand new non-cruddy cans, it does not store real well. Pour a can in the car, go top off the car with fresh, refill the can, lather, rinse, repeat. I don't know what the specs say, but emergency gas over a year old would not give me a warm fuzzy feeling.
-- aem sends...
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