which generator is best

lotek · October 2010

I am looking at several generators to provide battery backup and extra power.
I believe LP will provide the most trouble free fuel type but Im not locked into it
I have been looking into the Generac 8000, and the Briggs and straton 7000 stand by generators because of the electric start, They are American made and easy to get serviced but cost is twice as much as portable lp and deisel.
Any experience in this area will be greatly valued.

I know I dont need 8000 W to charge batteries and that it uses more fuel. However Ive seen no small diesel or LP generators, with electric or auto start, that are made in America, and I dont want to get stuck with a Chinise product with no support or parts.

monoloco · October 2010

Re: which generator is best

Onan makes a 3600 watt propane generator. As far as I know they are made in the USA. I have never had good luck with Briggs and Stratton.

BB. · October 2010

Re: which generator is best

What is your usage expectations... Less than 100 hours per year, or heavy usage?

In general, Generac generators are typically low cost, emergency gensets (typing about the portable gensets).

For an off-grid system--Look for 1,800 RPM, pressurized oil system with filter, Prime Power rated (if long term usage).

I would also look at getting a genset that is enclosed with a noise reduction system--The portable gensets can be real killers of peace and quiet if used a lot.

Also, look at the amount of power you really need to use... The 8kW Generac uses 0.9 GPH at 4,000 watt load (50% load). At less than 4,000 watt loads, it will use hardly any less fuel

You might want to get two gensets--a big and cheap noise maker for the occasional large loads/emergency use... And a smaller 2-3kW genset for the smaller loads. The Honda euX000i series are very nice, fairly fuel efficient for smaller loads, and quiet for small power usage.

Yamaha also makes some dual fuel smaller gensets too.

-Bill

Vic · October 2010

Re: which generator is best

I think that BB Bill has it pretty well nailed.

And, the Generac may be an American company, and they sell a number of real Industrial/Commercial gensets, but for the value-priced units, most of the guts will be sourced from the losest-cost supplier -- almost always in some other company. Many of the genset integrators will do similar things. Checked a couple of years ago with one of the larger on-line integrators, asking them just where the Alternator was made. They said that they had just stopped using Itialian alts, and were sourcing them from Croatia at that time.

In MHO, the value-priced units leave few corners uncut, as it is a very competitive business. However, if your needs are infrequent for the larger genset, then corners cut may not be a large issue, and the real Honda Inverter gensets work very well, are relaible and fuel-efficient. The Hondas may well be able to solve most of your longer run time needs.

LP is a great fuel, as often, others will deliver it to your tank, and it will last decades in storage. However, as you probably know, LP has gotten very expensive, and has considerably lower BTU content than Gasoline or Diesel fuels. So it is all a bunch of trade-offs.
Good Luck, Vic

BB. · October 2010

Re: which generator is best

I forgot to add--Tony/Icarus here recommends going to RV junk yards and finding their Onan or similar gensets. They are usually pretty cheap. Very quiet, reliable, with electric start--and you may be able to do a propane conversion on one (if it is not already propane).

-Bill

zeuspaul · October 2010

Re: which generator is best

Check out the generatorjoe website http://www.generatorjoe.net/subcat.asp?0=541

He has a lot of good supporting info on generators. His own brand 5-13 Kw diesel generators are American made with Kohler engines and electric start at what seems to me to be very reasonable prices.

Diesel would be my fuel of choice but YMMV.

My fire pump has a Briggs and Stratton engine (made in Japan) and so far I have no complaints.

Zeuspaul

lotek · October 2010

Re: which generator is best

Power consumption? I have an XW6048. No single large sorce requirements, unless I put in a deep well. My major concern is, how much power can I use at one time charging my batteries? Im guessing that equaliziing would be the largest draw. If XW runs the house power off the genset while charging then I
would need an extra 30 amps for that.

PS: I need 240v to connect to the inverter

Yes, Generac's smaller models have outsorced engines, They wont say to who, but strangly the service dep, gives locations which include Kohler dealers, and the engines do look just like Kohler's

As for the Onen 3600 LP, a great choice for off grid. Remote start and no transfer box wiring. New they are $3000, but I havent looked for used.

Can I get a Honda with electric start and install the Xantrex remote start?

RCinFLA · October 2010

Re: which generator is best

lotek wrote: »

Power consumption? I have an XW6048.

Can I get a Honda with electric start and install the Xantrex remote start?

Make sure you get 240v/120v model. The regular XW will not work on a 120v only inverter/gen.

I believe the smallest inverter/gen Honda makes that is 240v is the Honda Eu6500isa.

It's a nice quiet gen.

BB. · October 2010

Re: which generator is best

None of the small Honda's (euX000i) series (even the ex3000i with electric start) is suitable for autostart.

The estimated current to charge your battery bank is around 5-13% of the 20 Hour Amp*Hour capacity). Equalization should only be around 5% and usually every 1-6 months (as needed).

What is your bank's Amp*Hour capacity? Say it is 1,000 AH at 48 volts, assume charging flooded cell battery bank with 85% efficient Xantrex XW (guessing, using for example):

1,000 AH * 48 volts * 1/0.85 * 0.05 min charge = 2,823 watts min
1,000 AH * 48 volts * 1/0.85 * 0.05 min charge = 7,341 watts max

So, an 8kW genset would actually be a nice fit for a 1,000 AH 48 volt battery bank in the above example.

I believe the XW charger is power factor corrected--For non-power factor corrected charge controllers out there (most of them :grr:cry:)--You cannot run much above 50% rated power on a genset because poor PF will push the VA (not watt, VA=Watt/PF) rating over the genset's limit (VA, VAR, kVA, kVAR--all the same thing).

Plan on running at a minimum of 50% rated genset load. Run in morning (before 10 am) and pump as much current into the battery bank until the AC charge controller backs off on current (around 80-90% of battery capacity)... Then let the solar power finish off the last bit of the charge for the rest of the day...

You don't want to run the genset down to 2% of max charge current (float transition point) as that is a tremendous waste of fuel (the further under 50% you run the generator load, the more fuel is wasted--Fuel flow drops very little below 50% generator load).

-Bill

Vic · October 2010

Re: which generator is best

lotek,

Speaking of the EU series Honda Inverter models, two that I know of have Electric start -- the EU 3000isa, and the EU 7000isa (actually there are several models in the 5Kw - 7Kw range with El start), but only the larger one(s) have an auto-choke, which is almost REQUIRED for auto-start. And both of these models are Gasoline only. Some have converted these units to LP, but would probably void the warranty, if Honda knew of the conversion (who knows?). But, LP conversion should elinimate the need for choking.

IMHO, the EU 3000isa is the sweetest of all of the inverter gensets, BUT it outputs only 120 VAC (for the domestic USA market anyway), and might not have enough power for your applications. AND, I've been very disappointed with the ability of the EU 7K to charge my batteries through the Xantrex SW+ 5548s. Bulking is usually OK while using only one Inverter to charge, but with both yanking on the output at somewhat different times, the EU7K's output is pulled out of regulation, and the Inverter drops the generator input. And while absorbing, even one Inverter yanks the Honda out of regualtion, as it takes a large gulp of current, which is not tolerated by the Honda ... and so on.

As BB Bill and others have observed, having at least one of the Inverter gensets plus a larger one for the big jobs is often an unbeatable combo. For me, including the smallest, EU 1000isa in the mix is great as it is only about 32 Lbs wet, so for small water pumping jobs, soldering in the field, running an Automible charger etc, its portability makes it my most often-used generator.

Good Luck, Vic

Mangas · October 2010

Re: which generator is best

Generac also makes 1800 rpm, water cooled heavy duty propane units.

I have one of them a 15kw model SG015 with the digital H panel. With annual maintenance, I expect to get at least 10,000 hours out of mine. After five years, ours has 400 hours on it. Under the weatherproof and sound accentuated cover it runs quiet and dry.

For a back up off grid application, I would not buy anything less than 15kw and only a water cooled 1800 rpm unit.

Vic · October 2010

Re: which generator is best

Mangas,

Not to be too argumentative, but think that Generac DID make 15 KW/11Kw units which were 1800 RPM & LP fueled. However, in searching the Generac site just now, it appears that that the smallest gaseous fueled 1800 RPM genset that they currently offer is 22Kw in the Commercial series, and 25 Kw in the Industrial series (3-phase).

GeneratorJoe has a data sheet on your model, the SG015, but searching the Gnereac site there are no hits. That GJ data sheet dates from 1998, with a rev in 2002, which is a long production life for a genset if it were still in production.

The market seems to have changed in the past several years. Perhaps it is a lack of availability of automotive engines in the displacement range required to output the required power @ 1800 RPM. Dunno. And, finding these smaller gensets with Prime Power ratings seems almost impossible, now.

Furthermore, as you know, specing a larger genset only to get a heavy duty unit tends to waste a lotta expensive fuel.

On the used market, one can find lightly used gensets which were used in commercial/industrial sites which have very few hours on them, and at reasonable prices, so the OP may want to poke around on the used market. And think that the requirement of the OP was for a smaller unit anyway.

There are some nice RV gensets, as has been noted here, altho almost none of the RV LP units output 240 VAC, if that is a requirement.

Just a year ago I did a fairly exhaustive search for an LP fueled Prime Power rated genset in the 25 Kw range, and the selection was very limited. Here in CA, the emissions regs for stationary gensets have become much tighter, which may further limit the selection. Again, I dunno.

Am done, Good Luck, Vic

Mangas · October 2010

Re: which generator is best

I just had ours serviced a couple of days ago.

Learned that the problem now facing manufacturers is emission restrictions on automotive type engines used in the generators. This is one reason why the models and outputs change so quickly and vary a great deal from year to year. They are not permitted to use one that doesn't meet current requirements.

At one time I had considered upgrading to an exciter type unit (25 kw) but didn't want another potential headache having a smog controlled motor.

He told me to hold on to older my 1800 rpm. He has seen very few problems with them. To get a new Generac 1800 water cooled model, I believe Vic is right you now have to go to to 22 kw.

Models are changing so fast, I wouldn't be surprised to see lower outputs offered soon. In the meantime, I know the demand for well maintained used ones like mine is strong. I have two neighbors that would like to buy it if I ever decided to replace it with another Generac, Kohler or Onan.

That might be a place for the poster to start.

As far as the service goes, he replaced the plugs but the old ones looked brand new at 450 hours. With no fuel fuel filter to replace another benefit of the propane fueled units.

RCinFLA · October 2010

Re: which generator is best

Mangas wrote: »

Generac also makes 1800 rpm, water cooled heavy duty propane units.

I have one of them a 15kw model SG015 with the digital H panel. With annual maintenance, I expect to get at least 10,000 hours out of mine. After five years, ours has 400 hours on it. Under the weatherproof and sound accentuated cover it runs quiet and dry.

For a back up off grid application, I would not buy anything less than 15kw and only a water cooled 1800 rpm unit.

The 1800 rpm propane (originally gasoline based engine) are pretty poor on fuel performance. These engines have their HP peak at over 3000 rpm's so you have to put an oversized engine to get enough torque at 1800 rpm.

A friend of mine put a Generac 45 kW unit at his house. It actually uses a Ford Taurus V6 engine running on propane at 1800 rpm. It is a pig at sucking down propane, consuming almost a gallon an hour with no load on generator, over 4 gallons an hour at 75% load.

Mangas · October 2010

Re: which generator is best

Since we fuel the house and the genny with one underground fuel delivery/storage system, we decided that fueling architecture.

We only use our genny for off grid standby with an occasional 2 hour boot to the batteries a few mornings in winter, so we don't have higher primary power requirements that others may have.

Even then, our genny only runs about 60- 80 hours a year including exercising.

We derate our 15 kw unit to about 13 kw given our altitude. Anyone who a chooses propane fueled unit needs to take this into consideration.

chevenstein · October 2010

Re: which generator is best

Stay away from the Briggs 7KW unit. I have one and it is poorly made and runs like it's falling apart, which it actually is as I found metal filings in the oil filter the last time I changed the oil. This unit has the same single cylinder vertical crankshaft engine they put on cheap riding mowers found at big box stores but with an LP carb. A friend of mine had one of these mowers with the same engine and his had the little wig-wag they put on the crankshaft to counterbalance things come off due to bearing failure and grenade his engine while he was cutting his grass. This or something similar will happen to my genset sooner or later.

I plan on replacing mine with the oldest LP fueled unit I can find that I can get parts for. Something with a Waukesha, Continental, or similar engine made in about 1970 would be perfect. The only exception would be the Onans with the Wisconsin V4 engine as those are fuel pigs (though well made).

Most people don't like working on these things like I do, but you simply can't buy quality in the smaller LP units today. Even the Generacs like Magnas has from several years ago have rubber timing belts and even aluminum heads and pistons sometimes. Run it hard for a while and it will melt, I guarantee it. Don't get me started on units with catalytic exhausts and/or electronic engine management.

As far as US versus global manufacture, very little of mechanical quality is made in the US these days. You have to go to Germany, Austria, and the surrounding areas for that. (See Jenbacher, maker of gaseous fuel engines that will run 60,000+ hours between overhauls. I've seen one disassembled in person after nine years of almost continuous operation and the crosshatching in the cylinder sleeves was still visible).

BB. · October 2010

Re: which generator is best

As an FYI to California Residents... There is a new Air Pollution law coming into force... Started with diesels but affects many other engine types soon...

From a quick discussion I had, if you have, for example, three or more unlicensed vehicles (large fixed engines yet???)--You will have to register with some government agency and bring those vehicles into compliance.

Diesels may be ugly and difficult... LP will probably be a lot easier.

They are sending out notices to people now who own three or more tractors, forklifts, and such...

By the way, you may ask how they know who to send the notices to??? Well, have you purchased parts for any of these units? Have you supplied your name and address on the counter invoice? Have you supplied the serial number lately when trying to find the right part?

Well---there you go.

Here is a link to, at least, one of programs:

www.arb.ca.gov/msprog/ordiesel/ordiesel.htm

-Bill

Mangas · October 2010

Re: which generator is best

Chevenstein do the Onans build a 15 kw propane unit with an exciter can sans brushes?

I looked at their website and couldn't find much about their 1800 rpm water cooled units. My neighbor says he has an older 15 kw brushless propane model with an exciter. I couldn't find it as a new model. Another emissions casualty no doubt.

I think my 5 year old SG015 has a 4 cyl, 1.6 litre Mitsubishi automotive engine which I assume is better than a lot of what is out there now.

Interesting post.

Bill, imagine all those agencies now peering into our generator and backhoe habits. Bring older engines into compliance! Mercy, what's next.

chevenstein · October 2010

Re: which generator is best

BB: Good point. Note also that as far as I know most of the current (2010) Hondas larger than 2000W (including the EU series) are not legal for sale in CA. In the past 18 months or so I've seen maybe 70% of power equipment advertisements that I see add "Not for sale in California" to the bottom of their specs. I think cooler heads are prevailing though as the offroad diesel retroactive compliance mandate in CA has been suspended and even that program targeted mainly large commercial outfits. Also as money to enforce these things becomes scarce so too will become the enforcement.

Mangas: I have not paid too much attention to the Onan/Cummins units in the past several years since the smaller KW ratings disappeared from their line cards. That said, I believe the answer to your question is no, but I'd have to do some research. I'm not entirely against units that employ brushes or slip rings as long as they use simple consumables that I can source from a motor rebuilder. It's funny - of all of the generators I've seen at auctions, helped friends fix, or personally own all of the broken newer ones have bad engines (especially the Chinese Honda clones) and all of the older ones run like new but don't make power (usually bad brushes/commutators or excitation and regulation components).

Your 15KW unit will probably last a long time, especially given that you are maintaining it very well. My point is more that your unit could not survive prime operation for very long, whereas the cast iron hogs I love so much generally can.

Interesting indeed.

monoloco · October 2010

Re: which generator is best

You may want to check out Hardy Diesel, they put together some pretty nice looking generators using Perkins diesel engines and an Italian brushless generator, at an attractive price. Does anyone here have any experience with these units?

Vic · October 2010

Re: which generator is best

chev,

I was surprised to find thet Mangas's Generac IS Prime Power rated @ 11 KW. This design goes back more than a decade. The original data sheet was dated 1998. More recently, Prime Power ratings seem to have mostly disappeared in the sub-25 Kw range.

Mangas, think that the separate exciter alternators have not been made (in the 25 Kw range and lower) for 20 years or so. The brushelss self-exciting alternators seem to have been very trouble free.

BB, I am not an anti-government type, BUT some of this confiscatory governmental behavior in requireing retrofits etc seems criminal to me. The regulatory colwns can wind up converting citizens into anti-government types IMHO.

And, on used LP gensets, I did find a nice 18 KW LP Kohler -- 1800 RPM 2.4 L Ford powered with 42 hours on it. It dates from 1998, BUT does electronic ignition module (one coil/cyl & crank sensor), and an electronic govonor. No Catalyst, tho. I am not looking foreward to the ignition or govonor module going bad, as they are potted, and probably cost $1-$2 K ea. The engine is reportedly from a Ford Ranger PU. But it was on Craig's list at a very good price, so will give it a shot for the second power system at the off-grid location.

Good luck finding LP gensets that are smallish and rugged. Vic

lotek · October 2010

Re: which generator is best

after reading several forums and reviews, and talking to the rep from Generac
I have decided to go with the Briggs & Stratton Model# 40301 7000w. It has positive pressure oil, auto start. auto maintainence( once a wk) is set up for LP to start with. The Generac, my first choice, won't honor the warrenty if used on an offgrid solar home. and you must change out the needle from NG to LP + recalibrate the regulator. the Briggs is a twin cylinder vs single for Generac, and everyone works on Briggs motors.
Before I order this from Amazon.com, would anyone like to weigh in or talk me out of it?

BB. · October 2010

Re: which generator is best

There are some reviews here (good and bad).

One suggestion--Confirm there is a real live service person that will work on the unit if something goes wrong in your area (according to the reviews).

-Bill

techntrek · October 2010

Re: which generator is best

I have a Generac and keep up on a Generac forum. They aren't the best quality, but not the worst either. While they won't honor the warranty for off-grid, depending on the warranty they are offering you might consider rolling the dice. If its only one year you might have little to loose by going with the Generac (just make sure all problems found during inital checkout are corrected).

Vic · October 2010

Re: which generator is best

lotek,

Briggs may not be a very good name in the minds of many, but think that their V-twin is probably one of their better engines. A decade or so ago, the Briggs Vangard twin was a pretty good engine. I have an 8ish KW Vanguard powered tri-fuel genset. Has been fine, but has very few hours on it, so cannot comment on longevity.

In the power range 7 KW LP that you are looking for, there is essentially no alternative other than an air-cooled engine. Most suppliers of gensets, now, seem to have stricken off-grid use as an application covered under warrantees. A friend had a Generac single-lung powered LP genset used for hours per day in an off-grid application. He got about three years out of before the engine seized and threw a rod (or visa-versa). It probably had a minimum of 1500 hours on it. This is not too bad service given the original purchase price. And given that it was well-sized for his loads, it did NOT hog fuel during all of those hours, so I bet that he was $$ ahead vs oversizing the genset to get an HD unit ... and so on. He chose to run his welder/generator into the ground vs replacing the engine on the blown up one ... easier to find $$ to run something else than to repair the broke one.

You will probably be reasonably happy with your purchase, given the LP fuel requirement and power needed. Good Luck, VIc

dwh · October 2010

Re: which generator is best

Be advised that once you order anything with an engine from Amazon, and then put fuel in it - you cannot return it.

Apparently, the fuel vapors change the item to a hazardous material for shipping purposes and Amazon won't deal with that.

So you will be stuck with it once you run it.

Dave Angelini · October 2010

Re: which generator is best

Same with batteries on amazon !

lotek · November 2010

Re: which generator is best

OK! gen is in, ended up with the B&S 40248. It wont except an auto transfer switch because of its GFI main breaker, so you are supose to run every thing off of extension cords, My thoughts are to set a female 240AC plug at the box and use a cord with two male ends
My question is: because the gen has a ground to neutral bond, could I just not connect the ground wire to my female plug end, and thereby keep the ground fault main from working on the 240 line running to the inverter, or am I still gong to have to disconnect the ground from neutral in the Gen.???. would this still protect all my 120AC extension cords that I might plug into the generator?

BB. · November 2010

Re: which generator is best

I would look at bypassing the gfi breaker in the genset and lifting the neutral bond--especially if you have a neutral bond in the main panel.

If you still want protection for cords from the genset--get a gfi equipped extension cord (or short gfi adapter).

A gfi main breaker is a pain--Fault your hand drill, and you lose the power to your work lights.

Also the more branch loads you have, the more likely you will have false trips.

-Bill

lotek · November 2010

Re: which generator is best

I found this info online at http://members.rennlist.com/warren/generator.html
while seeking info on bypassing the GFCI breaker, and I would like your input as to using this a solution

"Some generators use GFCI breakers to feed the AC outlets. When connected to a panel that does not switch neutral the GFCI breaker will trip immediately. The affected generators have the neutral conductor bonded to ground to pass OSHA job requirements. Home or building electrical panels also have the neutral bonded to ground. This dual bond supplies two paths for return current to flow. The GFCI breaker will detect a difference in neutral vs line current flow and open the circuit.
To remedy this problem, the generator must be changed to supply a floating neutral or the transfer panel rewired to switch neutral. If the generator neutral is changed, the "NEUTRAL BONDED TO FRAME" label must be replaced with a "NEUTRAL FLOATING" or "NEUTRAL NOT BONDED TO FRAME" label. The generator will no longer pass OSHA job requirements. "

more good stuff at this site!

BB. · November 2010

Re: which generator is best

Looks fine. You can try and lift the bonding and leave the gfi breaker in. But I would bypass/remove the generator gfi to main panel connection.

-Bill

which generator is best

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