Buying Advice What is the best generator for our needs?

[Mickey_Fx]

Again that's why I'm a fan of the dual or tri-fuel approach.

It's a lot better to have several sources of power.

Agree with the multiple source of fuel. But again it depends upon other factors if multi-fuel use is easy. My larger genny I mentioned previously, a top end Honda, water cooled twin, was set up for propane (after market) when I bought it But the adapter for the propane didn't permit the use of gasoline by just changing fuel source. One has to be careful of any individual setup, one size doesn't fit all as the saying goes. And as I mentioned before, for propane, one needs to pay attention to propane's vaporization rate if low temps are in the picture.

 

[catdiva6]

Thanks everyone! Okay, Hope I answer all of the questions. We were looking for portable type generator for the house. Weather is mild here and our idea was to plug in cords to generator for lamps, hair dryers etc. We really could get by with our camp stove. I have no clue what the fridge watts are but that would be the only major thing (besides well pump). We do not need to run the entire house and turn on overhead lights etc. It does not need to turn on automatically when power goes out. Selected diesel because I read that these generators last longer than gas and we can store the diesel without it going bad. Didn't choose NG in case of major quake and lines go down.
Well pump specs are: 3HP, 1PH, VOLT 230, RPM 3450, AMP 14.5, SF MAX AMP 17.0, and a little blurry but looks like HZ or KZ 60 or 6.0
For house stuff we can really get by with a smaller unit, but it would be nice to have the well work especially if it was an extended outage.
I have looked on CL there was an Apache which I had never heard of but it's gone already...I do like a deal! Thank you

 

[RFB]

A 3hp submersible will have a substantive inrush current for starting the rotor and pushing against the water column. I have attached a graph showing a test for pump starting current for a well pump motor. The motor is rated 3/4 hp and 240V. It shows a maximum inrush current of about 18 amps which lasts only about 0.2 seconds.

3hp will be substantially more (3HP is more than 3 times the pump power) than that (18 amps at 240v is 4320 watts)

50 amps at 240v is 12,000 watts.

Hz is your frequency cycle, in this case 60

I am not sure what "SF MAX AMP 17.0" means, but if that is starting current it does not seem consistent with an operating current of 14.5 amps and 3HP.


Water is a key provision; if you solve your well pump power all of your other loads will be fine.

 

[BobRip]

Thanks everyone! Okay, Hope I answer all of the questions. We were looking for portable type generator for the house. Weather is mild here and our idea was to plug in cords to generator for lamps, hair dryers etc. We really could get by with our camp stove. I have no clue what the fridge watts are but that would be the only major thing (besides well pump). We do not need to run the entire house and turn on overhead lights etc. It does not need to turn on automatically when power goes out. Selected diesel because I read that these generators last longer than gas and we can store the diesel without it going bad. Didn't choose NG in case of major quake and lines go down.
Well pump specs are: 3HP, 1PH, VOLT 230, RPM 3450, AMP 14.5, SF MAX AMP 17.0, and a little blurry but looks like HZ or KZ 60 or 6.0
For house stuff we can really get by with a smaller unit, but it would be nice to have the well work especially if it was an extended outage.
I have looked on CL there was an Apache which I had never heard of but it's gone already...I do like a deal! Thank you

The refrigator is not a major load. Depending on the age it pulls 200 to 400 watts while running and 400 to 900 watts while defrosting. The hair dryer is around 1500 watts. Diesel can go bad. I don't know the details.

How deep is your well? It must really be something to need 3 HP.

 

[dave1949]

I wonder if we are assuming a submersible pump? Could be a jet pump. Do you know for sure catdiva, which you have?

 

[meburdick]

I wonder if we are assuming a submersible pump? Could be a jet pump. Do you know for sure catdiva, which you have?

I'm wondering the same thing... but, the specs the OP put up still show it could max out at just shy of 4KW required to start that pump.

 

[newbury]

Thanks everyone! Okay, Hope I answer all of the questions. We were looking for portable type generator for the house. Weather is mild here and our idea was to plug in cords to generator for lamps, hair dryers etc. We really could get by with our camp stove. I have no clue what the fridge watts are but that would be the only major thing (besides well pump). We do not need to run the entire house and turn on overhead lights etc. It does not need to turn on automatically when power goes out. Selected diesel because I read that these generators last longer than gas and we can store the diesel without it going bad. Didn't choose NG in case of major quake and lines go down.
Well pump specs are: 3HP, 1PH, VOLT 230, RPM 3450, AMP 14.5, SF MAX AMP 17.0, and a little blurry but looks like HZ or KZ 60 or 6.0
For house stuff we can really get by with a smaller unit, but it would be nice to have the well work especially if it was an extended outage.
I have looked on CL there was an Apache which I had never heard of but it's gone already...I do like a deal! Thank you

Ah, the details leak out -
If my off the top of my head math is correct the well pump would require about 4KW AT THE pump, like others have written if you have to run a LONG line, say 400' it would probably be a lot more.
The fridge would probably only need about 1.5 to 2KW.

To stay well within your budget I'd suggest an 8KW generator for about $1500, like the Generac or smaller Amazon.com: Generac 5747 XG8000E 10,000 Watt 410cc OHV Gas Powered Portable Generator With Wheel Kit And Electric Start: Patio, Lawn & Garden.

This would allow you plenty of power for the house and the capability to plug in the well pump on occasion.

And why I recommend tri-fuel:
From Cost of Gasoline vs. Natural Gas - MktNeutral - Seeking Alpha :

1,000 cubic feet of natural gas has about 1 million BTUs of energy. It takes about 8 gallons of gasoline to produce 1,000,000 BTUs of energy.

From Natural Gas Wellhead Price the cost of natural gas in California is about $5/1,000 cubic feet, or $5/1M BTU's compare this to the cost of gasoline about $36/ 1M BTU's.

So if you had to run the generator for 1 day on gasoline at 50% load it would take about $86 (9gallons@10hrs/tank@$4/gal).
IF your natural gas was ok the cost would be about $12. That's why I advocate tri-fuel for those of you lucky enough to have natural gas.

A new diesel 8KW generator seems to run about $7,000 plus.

A new from the factory 8KW tri-fuel costs about $2,500 plus Quick Find

The tri-fuel addition plus the Generac generator runs about $1,800.

And the bottom line really is at the end of your needs, how much do you have to use it?

I've been lucky and we haven't had an extended power outage (more than a few hours) since I started buying generators about 10 years ago. I have had the little "handheld" put to use on camping trips.

/edit -
And comments about "diesel going bad" nope, not if kept water and algae free.
And if you can get ethanol free gas and treat it with Stabil it's good for 6 months plus. Then put it in your gas burner car.

 

[meburdick]

Ah, the details leak out -
If my off the top of my head math is correct the well pump would require about 4KW AT THE pump, like others have written if you have to run a LONG line, say 400' it would probably be a lot more.
The fridge would probably only need about 1.5 to 2KW.

To stay well within your budget I'd suggest an 8KW generator for about $1500, like the Generac or smaller Amazon.com: Generac 5747 XG8000E 10,000 Watt 410cc OHV Gas Powered Portable Generator With Wheel Kit And Electric Start: Patio, Lawn & Garden.

This would allow you plenty of power for the house and the capability to plug in the well pump on occasion.

And why I recommend tri-fuel:
From Cost of Gasoline vs. Natural Gas - MktNeutral - Seeking Alpha :



From Natural Gas Wellhead Price the cost of natural gas in California is about $5/1,000 cubic feet, or $5/1M BTU's compare this to the cost of gasoline about $36/ 1M BTU's.

So if you had to run the generator for 1 day on gasoline at 50% load it would take about $86 (9gallons@10hrs/tank@$4/gal).
IF your natural gas was ok the cost would be about $12. That's why I advocate tri-fuel for those of you lucky enough to have natural gas.

A new diesel 8KW generator seems to run about $7,000 plus.

A new from the factory 8KW tri-fuel costs about $2,500 plus Quick Find

The tri-fuel addition plus the Generac generator runs about $1,800.

And the bottom line really is at the end of your needs, how much do you have to use it?

I've been lucky and we haven't had an extended power outage (more than a few hours) since I started buying generators about 10 years ago. I have had the little "handheld" put to use on camping trips.

/edit -
And comments about "diesel going bad" nope, not if kept water and algae free.
And if you can get ethanol free gas and treat it with Stabil it's good for 6 months plus. Then put it in your gas burner car.

A gallon of *pure* gasoline MAY contain UP TO 120,000 BTUs (it has been specifically measured a. Since Ethanol is approximately 33% LOWER in its BTU capacity per gallon, you have to understand that you're simply not going to get anywhere near the 120,000 mark for a gallon of gasoline from the pump at a filling station.

Winter blended fuel is even lower.

That all makes the cost comparison between gasoline and natural gas is even wider than what you might think already.

Diesel has a higher BTU capacity than gasoline by about 10-15% (measured at 129,500). that isn't much of an increase, though, so it isn't going to save you much (if anything, since diesel is a higher cost fuel).

Propane is a terrible alternative as it has 1/3 less BTU (almost on par with ethanol) than gasoline.

CNG (Compressed Natural Gas) is saturated with about 900BTU/cubic foot. 1,000 cubic feet of CNG compares to about 8 gallons of gas in terms of BTU potential. Huge difference.

As far as diesel not going bad, good luck. Keeping moisture out of the fuel is almost impossible to do, and *is* impossible for the homeowner. There's a reason that every single diesel fuel conditioner on the planet has chemicals in it to break down, suspend, and disperse water in the fuel.

 

[newbury]

<snip>
As far as diesel not going bad, good luck. Keeping moisture out of the fuel is almost impossible to do, and *is* impossible for the homeowner. There's a reason that every single diesel fuel conditioner on the planet has chemicals in it to break down, suspend, and disperse water in the fuel.

Investigating threads on TBN there are numerous reports of multiple year storage of diesel, unlike untreated ethanol laced gasoline which seems to start to go bad after a few weeks.

I don't understand why you state:

Keeping moisture out of the fuel <snip> *is* impossible for the homeowner.

Are you a homeowner?

Example

Diesels in backup power service have large tanks that sit there full until the power goes out. Unless the outage is extended, the fuel may well sit in the tank for many years without being used, except for the occasional maintenance running.

I have had diesel fuel sit in a boat for at least six years that ran the engine fine. Nothing was done to it except the addition of a biocide when the tanks were filled.

I've diesel in a van that sat for two years and fired up this summer after I replaced the glo plugs. Because of that I did a pretty wide search recently.

Perhaps you failed to read this part of my statement:

And comments about "diesel going bad" nope, not if kept water and algae free.

By keeping the tank topped off (to keep the air from it) and adding an appropriate treatment to take care of water AND algae I've had great success in keeping fuel. I called it proper planning, storage and treatment, you can call it luck.

From BP (the folks that brought you the black beaches of the Gulf Coast)

In underground storage low sulphur diesel fuel can be expected to last at least 5 years provided steps are taken to keep water and fungus out and potentially up to 10 years or more with regular inspection.

 

[RFB]

I am unaware of the test conditions; I obtained that at a generator power company website looking for starting current for the OP's 3hp pump. (I thought that for a submersible, his stated current seems low.)

I would say that your numbers are pretty logical with the differential being water column size. Inrush is momentary but real, hence the surge capacity on small(er) generators.

I run two separate systems depending on the duration of the outage. For one lasting a few hours, I use a Mitsubishi MGE6700REU Maximum Output 6,700; Rated Output 5,800. This runs, without trouble, 1hp 260 foot submersible, reefer, 2 freezers, lighting and door openers.

For multiple day/week outages I use a 45KW Kubota/Marelli Generator through 400 amp manual Tfer switch that can run everything at once (7 tons of Heat Pump included.)

Do you know the test conditions for that graph. The test I have done on my 3/4hp pump is that it draws a steady 25 amps before settleing down to around 6.5 amps. My 1hp drew 30 then down to 8. It just shows that every installation is different.