# Advice on natural gas generator



## Tambourineman (Aug 6, 2014)

Most of the threads I found here involve converting a gasoline generator to natural gas, or propane.

One issue is that NG generators run hotter than gas ones and some say this might void a warranty.

I would like a generator designed as an NG generator from the get go but would allow conversion to propane as a back up. Copnversion to tri fuel to add gasoline would be a plus but not a determining factor.

I am also concerned with noise levels as I am on a 5,000 sq ft postage stamp sized lot so neighbors are close.

I confess I haven't down my homework yet as to size but I only really need it to run two recirculating pumps on my NG furnace (one pump was replaced a few months ago and the other is an original and probably a power hog so it would have to be replaced) and a modern energy efficient refrigerator. Oh, and my wife says it needs to also run a hair dryer. LOL I'm thinking 3,000kw would be more than enough.

Can someone provide some recommendations on NG generator makes and models, or why my approach is not practical.


----------



## Waypoint (Jan 28, 2014)

Tambourineman said:


> I'm thinking 3,000kw would be more than enough.


I'd say 3 megawatts (3,000 kilowatts) is a pretty lofty goal. You're in turbine territory here. 

3 kilowatts (3,000 watts) might be more what you're thinking. In this case, you can get a Yamaha delivered pre-tuned and ready to go here:

EF30iSE Propane Natural Gas Generators

I use a Honda EU3000is similar to this, but just run gasoline. It only burns 1.5 to 2 gallons per 8 hours of runtime at our loads, not worth the trouble of converting it to NG in our case.

It comes down to 3 design decisions:

1.) How are you going to connect the gen's output to your house?

2.) How are you going to feed NG to the generator?

3.) Where will you locate the generator?

For our house the NG meter is on the opposite end of the house vs. the breaker panel (and therefore the transfer switch.) No interior black pipe anywhere near our garage, where the breaker panel is. And the transfer switch we used (Reliant) must be mounted next to the panel.

It would be major trouble either bringing NG out to where our electrical connection point is, lots of black pipe (or lots of 10/3 electrical wire to move the transfer switch outdoor inlet box) for very little return on investment. 

If you're lucky enough to have your NG and breaker panel in close proximity it wouldn't be so bad. So figure out the 3 factors above and let us know what you decide.


----------



## Tambourineman (Aug 6, 2014)

Ha, ha. I meant 3,000 watts.

I am just in the initial stages of researching this.

Unfortunately both my electrical panel and gas meter are in the front of the house and I want to put the generator in the rear of it or by the garage. what I don't know is if it can be more or less snug to the house's foundation, or if CO2 fumes could be an issue.

I already have piping and wiring to the back end of the house. There is wiring left in place for an electric stove that was replaced with a gas one, and of course the gas piping to the stove. I have not checked the pipe size yet and I think it's supposed to be 3/4 inch. Without measuring, the pipe seems much bigger than that although I don't know how thick the metal is. The house was built in the 30's.

There is an (too small) auxiliary breaker panel in the garage, but no gas. so I expect if I locate it near the garage, then I will have to dig and bury new wiring and piping. I am not thinking I would put it in the garage.

Using NG adds an extra dimension, but the wiring issue would seem to be the same if I went with a gas or diesel gen (I am also tentatively thinking of looking into a Lister diesel).

While it would be nice to be able to run on gasoline as a back up to a back up, gasoline degrades too fast, so I want a fuel that I don't have to keep rotating.

I don't intend for this to be a DIY project.

Thanks for link to the Yamaha EF30iSE. It is much better than the others I found in my preliminary search.


----------



## markd (Feb 22, 2014)

I'm no expert on generators, but this is what I was told when I did my install. I converted a gas generator to tri-fuel, using a kit. They really made a point of telling me to limit the distance between the gas meter and the generator. The closer the better. I believe it is a matter of the volume of ng available. Additionally, they recommended using a large diameter hose for the hook-up. I ended up tapping into the NG line just after the meter (1"pipe) before it entered my house. Brought the pipe down to 3/4" and used a 3/4" rubber hose to connect to the generator. The generator runs great with this set up. I probably could have used 1/2" hose to the generator, but I didn't want to take any chances. I hope this helps......


----------



## Tambourineman (Aug 6, 2014)

Thanks for the advice. I have to go look at my piping but that won't be until Monday at this point as I am leaving for ME this afternoon for a long weekend.

My gas and electric stove used to be in a different location before we remodeled the kitchen. I assume they just extended the old gas line further back and to the side to get to the new location, but maybe they capped the pipe and ran a new one.

My gas meter is in the basement so there is no way to tap it outside.
I have never paid any attention to my gas piping. Is there usually a separate line for the furnace, hot water heater and stove or do they all run off a common pipe until they split off? Next week I'll go follow the pipes running from the meter.


----------



## PeteCress (Feb 9, 2014)

Tambourineman said:


> ...what I don't know is if it can be more or less snug to the house's foundation, or if CO2 fumes could be an issue.


I claim no expertise, but I have read posts by a guy in Florida who says that several families die with each power outage just because of CO infiltration from a gennie that seemed like it was in a safe place.

I've got mine in a garden shed about 50' from the house. When the time comes, I deploy a 100' 10-3 extension cord between the gennies and the transfer box.




> Using NG adds an extra dimension, but the wiring issue would seem to be the same if I went with a gas or diesel gen (I am also tentatively thinking of looking into a Lister diesel).
> 
> While it would be nice to be able to run on gasoline as a back up to a back up, gasoline degrades too fast, so I want a fuel that I don't have to keep rotating.


Can you get propane where you live? 

We have nat gas, even though I do not have the gennies set up for it. 

But when I obsess about fuel storage and availability, I start thinking that maybe I should compare the cost of a 500-pound propane tank behind the shed with the cost of plumbing natural gas to the same place. It would have the additional benefit (yes, this is a stretch, but I saw it in Sandy's aftermath) of being able to function if/when the natural gas gets shut off.




> Thanks for link to the Yamaha EF30iSE. It is much better than the others I found in my preliminary search.


I haven't read the rest of the thread, so maybe you have seen it already: but you can get 3600 watts continuous with a pair of Honda EU2000i's for a couple hundred less than the cost of a like-quality 3kw inverter generator - with similar or even slightly better fuel economy.

That's where I am. In outage mode, our house cruises on 800-1200 watts and the transfer switch automagically shuts down pre-selected circuits for pre-selected times when the limit is broached. So the second EU2000's function is 97% redundant backup and only 3% convenience (as in running the big micowave, coffee maker, and toaster around breakfast time without having to listen to the UPS' beeping in the computer room, LAN closet, and under the Kitchen TV).

To justify the backup I figure that eventually everything breaks down and, since my gennie only gets used during power outages, it will fail during an outage.


Of course one more cost justification would be between all this crap I have purchased (generators, fuel cans, cutover switch....) plus it's care and feeding and taking the wife on a mini-vacation in any one of several nearby hotels during power outages... -) That's what the couple across the street did during the last (7 days) outage. OTOH, I wouldn't want to smell their freezer/refrigerators at the end of it...


----------



## Waypoint (Jan 28, 2014)

PeteCress said:


> ustification would be between all this crap I have purchased (generators, fuel cans, cutover switch....) plus it's care and feeding and taking the wife on a mini-vacation in any one of several nearby hotels during power outages... -) That's what the couple across the street did during the last (7 days) outage. OTOH, I wouldn't want to smell their freezer/refrigerators at the end of it...


Decent hotels with electricity AND available rooms were mighty hard to come by here in Northern NJ after Sandy.


----------

