backup generator

[Peter Klaassen]

With the off grid living comes the necessity to be your own power company. In the fall and winter we are using more power than we make with the PV panels and make up the difference with a diesel generator. This has recently swallowed a pre-heater part and stopped working. The question I have is what do I replace this beast with. I am looking for a 6000 W generator - any advice on what to get? I am leaning towards gas now and a Honda if I can find one reasonably priced.
Thanks for the input.
P.S. eventually I will install a wind generator, but that is still a ways off.
Happy New Year to the Greens!

[Dale Sheler]

The problem with that size gas generators is they are screamers, an 1800 rpm diesel unit is gonna be longer lived, onan makes some excellent smaller diesel units.
I have bought a couple from junk yards that take in large RVs, most of the big ones have good generators with all the remote start stuff already there.

[Ralph Day]

Hi Peter
How drastic was the crash of your present genset? It might be cheaper to repair than replace,.

What are you charging with, inverter or external charger? What capacity for charging will it support? Your generator choice depends on a lot of factors.

I have a new under 15 hours on the clock Subaru 5kw (4.5 continuous) diesel unit for sale. PM me for price and details...shipping accross the County (not Country) is free :cheesy:

Ralph

[Ralph Day]

Peter,
I tallied up my totals for the year this morning. My 1kw wind turbine, on 80'tower, about 4.5m/s wind speed provided 521kwhrs of energy this past year, solar was 2200kwhrs. Best year was over 600 for wind, but unless you get into a 2.5-3kw unit don't expect a whole lot from small wind.

Part way through the year production dropped, then stopped before my spring re-build of bearings. That probably accounted for 5% drop overall, perhaps.

I've come to the conclusion that the $$ put into small wind installation ($5K?) would harvest much more energy if used to install more PV .

[Peter Klaassen]

I am using the charging function of the Outback inverters to keep up the battery bank November to February. I have rented a 5000 W Honda which doesn't seem up to the job. The solar panels aren't doing much these days with the lack of sun - even if there were more of them. I am leaning towards another diesel but 1800 rpm instead of the 3600 rpm machine that swallowed part of the glow plug. It is going to be a toss up whether I will be able to rebuild this Hatz machine at a reasonable cost. It had only 600 hours on it. Even just for interest sake I will likely invest in a small wind turbine.

I appreciate the input from you all.
Pete

[Ralph Day]

Youch! My Subaru doesn't have glow plug on it, but it is 3600rpm. Noisier than my 10kw Simpower too.

If you're using 2 inverters to charge you should probably be into a 7kw or higher inverter. The problem is once you get past bulk and into absorb you are burning fuel for less and less return on $$.

The Honda inverter units can be synched together to provide more current in bulk, then they back off as the load goes down. I'm pretty sure 2 of the 2kw units would provide enough power for charge in a timely manner...2 of the 5kw units definitely would. Depends on the pocket book.

Looking at strictly dollars and cents the utility is the best generator. A complete charge from 15% discharge for me would be about 10kwhrs of Hydro One juice...about $1.00. The same charge result with my diesel genset, at 2.5lphr x 5hrs x $.85/l = $10.63 No comparison really, except that I only ran the genset for 150hrs per year $318 per year, and at $40 per month just for hookup to utility $480 per year. You pays your money and you takes your choice.

What size of Hatz engine is your damaged one? I did see Hatz engines on little pallets at Foxboro Equipment, so they are available...for a price.

Mine has 18.8 amps 240volts capacity, 9 amps 120vac charging for each inverter. How much is that below what they can use?

Ralph

[Brian McGowan]

I have decided to build a battery charger made of a small engine and an alternator. I made one from a lawn mower engine and an alternator. I actually used it 2 times since I made it to keep my battery up while I actually run my house on the inverter. It makes a kind of hybrid system. Most of the time the battery is being charged but when sudden load occurs beyond the current being supplied by the alternator, the battery can help with the surge and then go back to being charged. You get a little better efficiency since you are charging the battery directly and when you get into the less power demanding stages of the charging process you can decrease the engine speed and save fuel. At no time does it have to be run at a particlular speed to maintain a given frequency. I have mine geared up to a little more than 2:1 so I can run it at about 1500rpm and the alternator is running at about 3000rpm.
I have since purchased a small water cooled 6.6hp 1 cylinder diesel engine for this purpose and I am planning to make a combined heat and power arrangement and I want to run biodiesel and waste vegetable oil in it.
Xantrex makes an alternator regulator with proper charging profiles for many types of batteries designed to run alternators for marine and off grid charging. There are battery and alternator temperature sensor options for this so the profile will be adjusted accordingly and the alternator protected.
Alternators are available in several voltages and in currrent ratings of 100+ amps and you could run two from a single engine.
Anyway, just wanted to propose an alternative that you may not have thought about.

[Peter Klaassen]

I have purchased a Yamaha EF6300iSE to replace the Diesel generator. It is gas powered and uses an inverter and variable engine speed to increase efficiency. It also seems to unload as the MX charger increases output. The power produced is also "cleaner" which is a concern now with all the computers found in appliances these days. The Outback FX's are limited in their maximum draw to 20 amps but it doesn't take long to reach the absorb level for batter charging.
The Yamaha is much quieter and seems up to the job required. Advice from Maier Hardware's Dave Green seemed to indicate that I wouldn't have enough of a load to warrant a large 10-12 kW 1800 rpm diesel. The expense of such a machine was a stumbling block. I would recommend to any other generator users that they ensure the exhaust is not being drawn back into the generator - I had my machine in the barn and in a tarp garage which may not have allowed enough fresh air into the generator. I will have a direct vent outside on the new set up.
Thanks to Mario for the use of his back up generator.

Pete

[Ralph Day]

Hi Peter
Glad to hear you found a good replacement for your earlier genset. The little diesel units are not meant for yours and my type of applications...long runs regularly, for battery charging.

Yamaha is a good brand to go with. The inverter type generators are all over now, clones galore, but sticking with a brand name is always a good idea. Yamaha, Honda, Subaru even. Service and warranty should be no problem for a Yamaha.

I have read some threads/posts regarding the inv/gen charging at low output levels. There was concern about the waveform of the output being able to provide enough power for charging to occur. Most charging clips the tops off of the sine wave, with the rest of the waveform being lost as heat in the generator windings. This is the reason for de-rating a generator to 70% or so for charging. I didn't know this when I first moved off grid and had my big diesel genset shut down once or twice for no apparent reason...it was overheating the alternator. (turns out the load was really only on one half of the alternator, but that's another story) If you have any problems charging when in absorb (near end of cycle) this may be something to look for...if you have an oscilloscope of course. If you just plan to charge a large amount of bulk amps then there shouldn't be a problem. Some time in the am before the sun contributes much might be a good regimen.

My generator shed has a barn ventilation fan at one end and large screened air inlet on the other. When the genset runs the fan runs drawing way more air over the unit and radiator than the engine fan alone could do. ( the engine fan was about 4 inches smaller than the cowl around it so a lot of air just got bounced back into the room thus heating it a lot).

I'd suggest an excess of cooling air moved over the alternator and engine would be pennies of prevention now vs a pound of cure later. TSC, Princess auto have 10-16 inch ventilator fans. Just have it plugged into the house service so there is not an unbalanced load on the 240vac output of the generator. (i noticed unbalanced output on my Subaru when I put 2.5kw of 240v heaters on, then added a 120v heater too. The generator surged rpms as it tried to balance output).

Ralph

[Chris Olson]

I have decided to build a battery charger made of a small engine and an alternator.

I live off-grid and my little gas charger is used almost exclusively to generate standby power vs using the AC generator. I have a 6 HP Tecumseh driving a Delco 12SI and it will generate 2 kWh of power on about 1 qt of gasoline. With gas at $3.19 a gallon around these parts that's still about 40 cents/kWh for standby power, but time has proven to me that it's cheaper than running the AC genset.

I've thought about trying to design a voltage monitor for the battery bank to auto-start the gas charger when the voltage drops below bank nominal. But when I looked at the reliability factor of getting something like that to work it just didn't seem worth it since there's ample time between where the bank gets low to completely hammered. And it only takes 3 minutes to get it fired up and putting power back into the bank.

This is a photo of my little unit - it sits outside year 'round with a plastic cover over it. It will start reliably with three or four gentle tugs on the starter rope even at 20 below.
--
Chris

[Ralph Day]

Hi Chris
A friend of mine has a similar 24vdc setup for charging batteries. This fall we couldn't get it to start and run reliably. When we drained the fuel tank there was 25% water and gunk in it. The engine had to be taken to Honda ICU for repair. The fuel had also contaminated a boat motor tank in the summer (I was there for that too, but didn't diagnose the problem then). Some gas station was pumping out of the bottom of the underground tank in the summer.

The lesson learned was to check fuel before putting it into power equipment or their fuel reservoirs.

Balmar makes voltage regulators for lots of applications, didn't know if you have one installed.

http://www.balmar.net/regulators.html#

Ralph

[Chris Olson]

Hi Chris
Balmar makes voltage regulators for lots of applications, didn't know if you have one installed.
http://www.balmar.net/regulators.html#
Ralph

Hi Ralph,

Those little Delco automotive alternators come either 12 or 24 volt (the 24 volt ones for off-road construction equipment have a different rotor, stator and regulator) and I just use it bone stock. When the bank voltage gets up to fully charged the internal regulator backs off the field and the amps and maintains the system voltage.

When I'm working in the shop and using lots of power I'll start it and let it run at dead idle with the regulator in the alternator grounded so it runs full-fielded. I have a bolt in the "D" hole on the rear of the alternator frame that I screw in until it contacts the regulator ground. It's a "trick" to get more amps out of it at slow speeds but it's hard on the field winding in the alternator long term so I don't do that unless the engine is running at dead idle speed (about 1,500 rpm).

I have mine geared at about 1:1.5 and that works really well with the 6 horse on a 90 amp.

My system is 12 volt. I have a lot of 12 volt stuff in the house (power jacks for mobile laptop power supplies, cell phone chargers, microwave, florescent lighting etc.) that I'm not willing to give up or using a step down transformer to use on a 24 volt bank. So I've stuck with the 12 volt, which I originally started with.
--
Chris

[Chris Olson]

I've come to the conclusion that the $$ put into small wind installation ($5K?) would harvest much more energy if used to install more PV .

This can depend in a large part on where you live and local weather and wind conditions, though. Where I live solar panels are just about worthless in the winter time. If they're not covered with a half inch of what I call tungsten carbide ice because it's tougher than any steel known to man, they got 10" of snow on them. So you work for two hours to clean and scrape off your solar panels and then the sun goes under and doesn't shine for a week so Mother Nature can regroup and deposit variants of non-liquid forms of water on your freshly cleaned panels again.

Meanwhile the wind turbine "just works" in the winter time. I've only had to lower the tower twice so far this winter to de-ice the blades when ice got built up 1-2" thick on them. Way less maintenance on the turbine in the winter time than the solar.

Today, a pretty much typical winter day here, I have 4.88 kWh from the turbine so far and .41 kWh from 1,230 watts of solar power. I need 10 kWh per day to keep my house lit and the turbine will make most of it.

In the summer it's the other way around - the days are long and solar works great and makes the bulk of our power. Meanwhile, the turbine spends a lot of time spinning on the tower practicing and staying limbered up for when a storm blows thru so it can make a huge surge of power that you can't even store and use later. So you may as well crank the tail on it and just leave it shut down to save on bearings.

I think the two really compliment each other for the most part, and I know of few off-grid folks who can live with just one or the other without putting a lot of hours on the generator.
--
Chris

[Chris Olson]

This is for the off-grid folks. They said on the radio 20 below tonight, which means where I live near the river bottom it'll be 25 below. They keep saying 30 below tomorrow night. On nights like this I run the gas charger just to keep it limbered up and keep the batteries topped off during our peak evening loads:

http://www.youtube.com/user/DairylandWindpower?feature=mhum#p/a/u/0/Qnd9NzfjiNk

It seems no matter how much money a person spends on wind and solar power, we still depend on the generator. When it's 20-30 below I run the generator every five to six hours for two hours at a time just to keep it from getting too stiff in case something would happen where I absolutely would need it to keep stuff from freezing up.

I've many times wondered what other off-grid folks do when they have to get their diesel gensets started at 20-30 below, because even keeping a gas unit limbered up enough for an emergency is a chore at those temperatures. While the diesel is more fuel efficient, there's just no way we could make enough power with the turbine and solar panels to keep one plugged in so it would start. So the little gas charger is what keeps us lit about 99% of the time for standby power just because it's so reliable.
--
Chris

[Dale Sheler]

I hear on he weather tonight you guys are gonna be in a wind chill advisory thursday night through friday

[Chris Olson]

I hear on he weather tonight you guys are gonna be in a wind chill advisory thursday night through friday

That's good because that means the turbine will come to life and make power. I can deal with the cold as long as I got power :bigsmile:

--
Chris

[Ralph Day]

Chris,
I have a 10kw water cooled diesel genset. To get it to run there's a coolant block heater and a magnetic oilpan heater. While I don't run it below -15C i do sacrifice 30 minutes of battery power to warm it up before starting when the temp is below freezing (maybe 15 minutes).

When the temps get as cold as you describe it's either windy or the next day is going to be sunny (or it has been sunny and batteries are full SOC). Once had an inverter problem and had to do as you suggested...run for an hour, off for 4, on again and so on. When the genset was off I had a small propane radiant heater in the shed to keep the chill off. On low one BBQ tank (20lbs) would last for about 1 day.

If you're worried about starting, I'd suggest building a small enclosure/box for the unit and invest in a little propane radiant heater...the kind using a 1lb cylinder. Need to run? pull out the genset or pull off the box and pull the cord...should start up easily.

In short, I don't worry about starting in the severe cold. I try to keep the SOC up before those conditions hit, or at least keep a close eye on it.

All this information is from my pre-utility hookup existence. Now I have utility power as backup to my solar and wind, backed up by my 10kw genset which is backed up by my 5kw Subaru diesel genset. All that's lacking is a hamster in a wheel hooked to a PMA home-made generator:laugh:

Ralph

[Chris Olson]

In short, I don't worry about starting in the severe cold. I try to keep the SOC up before those conditions hit, or at least keep a close eye on it.
Ralph

We do the same. But something always happens. Our water is froze up this morning - not a drop comes out anywhere and it only got down to 24 below F. Supposed to be 30 below tonight with 55 below wind chill. So the only option I got is to start the big Cummins genset and use the welder to thaw out pipes. I keep my Dodge Cummins in the shop so that will start - I got hydraulic couplers on the cooling system on the pickup so I can drive out to the generator shed and hook them up to the cooling system on the N14 to warm it up and get it started. Starting a 250 kW genset at 24 below is not one of my favorite things to do just so I can thaw out water lines.
--
Chris

[Ralph Day]

Water lines from well to house or within house (yikes!)?

250kw genset? Do you run a quarry or something? Maybe a great deal? That would be a lot of dump loading to keep the genset loaded to 50%:laugh:

Ralph

[Chris Olson]

Water lines from well to house or within house (yikes!)?

250kw genset? Do you run a quarry or something? Maybe a great deal? That would be a lot of dump loading to keep the genset loaded to 50%:laugh:
Ralph

The water was froze in the line out in the front yard. I got some more snow piled on it now.

We have a farm here and that genset provides our prime three-phase power to run our grain handling system. It burns 19.5 gallons an hour and that's why I use the gas charger for standby power.

I've looked at Generac, Hobart and several other brands of AC generators for the house and shop in the past, but the gas units cost too much to operate and the diesel units won't start here in winter without some sort of auxiliary heat. By the time I'd use propane for aux heat to get a diesel unit started, I can just burn gas or LP in the generator engine, and neither is very cheap - it still comes in at over 70 cents a kWh.

So I continue to use the gas charger which comes in at about 40 cents a kWh. I haven't really found a cheaper way to generate standby power yet.

Once you start a standby genset it's not really efficient until you get it up to about 75% load. At only 5-10% load the cost/kWh to operate that AC genset is astronomical. I think it's an equation that all off-grid folks wrestle with.

----------
I'm updating this post on Friday, Jan 21. It was 39 below here this morning in the Yellow River Watershed. We needed to heat some water this morning with the inverters so my wife could wash dishes. So I went out to start the gas charger. That thing started at 39 below - sitting outside under a plastic tub that keeps the snow and rain off it - with 0W-20 oil in it. I turned on the key, put it on full choke, and primed it three times - then pulled the rope thru about a dozen or so times really slow to limber it up, pushing the primer every three pulls. Then I pulled on it harder and it would fire once every time I pulled on it.

After about 20 times like that, pushing the primer once every 5 or 6 times, it started. I backed the choke off one notch and let it run for a minute until it started to load up, then backed the choke off to full open. It settled into a smooth idle, I pressed the button on it to energize the field in the alternator and it was putting out 35 amps. I opened the throttle until it was pushing 75-80 amps, went in the house and threw the switch for the water heater and it started heating water.

39 below zero and I can get my standby started with no aux heat. That's about as reliable as they come. I think it will be awhile before I would trade that thing for a little diesel generator :-)
--
Chris

[Brian McGowan]

As I read your description of starting in cold weather I am very thankful I do not live where you live. The lowest here this year so far has been 2 degrees and that is way too cold for me. When I bought the diesel engine for my project I already had made my lawn mower engine version. I bought the diesel to run on waste vegetable oil and biodiesel and to play with a combined heat and power arrangement. I had thought about starting the diesel in cold weather and figured I'd keep the lawn mower version as way to get things going since it would start in colder weather. I have thought of ways to route the exhaust from the gas engine around the underside of the diesel to help warm it up and make it easier to start as well as using the power to keep the batteries up and help crank the diesel until it starts. I am still not sure about the feasibility of this arrangement but it sounds good to me in theory. I am still thinking this all through. I am sure most offgridders start their diesel engine in fall and run it throughout the season so it stays hot generating electricity and scavaging the heat for use in the house.

Brian

[Ralph Day]

Brian,
Starting a diesel in cold weather is all a matter of planning. If you have a non-water cooled engine it's more to plan for. My water cooled big boy has an inline coolant heater...you sacrifice some battery/inverter power to preheat for start. For air cooled I'd suggest a radiant propane heater and a small enclosure. A part bottle of propane (camping stove size) to heat for an hour or more and then fire it up. I'm speaking from my vast pool of in-experience here, I haven;t tried to start my 5kw Subaru genset that way...yet.

It would be madness to run a genset 24/7 for months on end. Any significant others, or neighbours would surely strangle you :laugh: I have had to cover for an inverter outage years ago and in that case I would run the big genset for 2 hours, then shut down for about 4, then run again. Overnight I left the radiant heater running in the generator shed and it started ok after 9 hours. This was in December with -5 to -10C temps.

Ralph

[Peter Klaassen]

The dead engine that spurred this thread has been examined and is doomed to the wreckers. I am looking for a replacement engine - 3600 rpm, about 10 to 12 hp- that I can use to resurrect the generator end. The Hatz 1b40 has a number of issues and is good for parts only. There aren't many hours on the generator and it seems a waste to trash the whole thing. Any suggestions would be appreciated. I am not sure I would spend more than $1000 to get this thing operating again.
Thanks,
Pete

[Chris Olson]

Brian,
Starting a diesel in cold weather is all a matter of planning.


There's situations where it's just not practical. We use Fahrenheit here so I had to do the conversion - it was -26 C here this morning.

Getting a diesel started at -10C is not even a challenge. That's balmy weather. The amount of energy input required to start one at -20C and below negates any fuel efficiency advantages it has. May as well use the energy input required to preheat a diesel on running a gas unit and get the power right away.

Just about everything I own is diesel powered, including my lawnmower. But for me gas still works better for the generator just because it has to start and run when I need the power. Wasting energy input to get it warm enough to start just doesn't pencil out.
--
Chris

[Chris Olson]

The dead engine that spurred this thread has been examined and is doomed to the wreckers. I am looking for a replacement engine - 3600 rpm, about 10 to 12 hp- that I can use to resurrect the generator end.


Couldn't you just bolt a Kohler Command CS on it, or similar? Those little Kohlers have cast iron sleeve, forged crank, pressure lubrication and experience has proven to me that they cost less per hour in fuel, maintenance and repairs to operate than a little diesel. You can buy one, brand new, for less money than it costs to fix that little fuel pump on a Hatz 1B40.
--
Chris

[Brian McGowan]

Ralph,
Most of the times I have heard of people running diesels for generation for extended periods of time, they have been talking about lister type engines running at 650RPM. Usually they are scavaging as much heat and power as they can and have made interesting ways to quiet even the exhaust noise. I will agree that running a standard diesel genset continiously would create quite a racket and it is likey you are right about the neighbors and wife complaining.
I will be happy to run my little engine at 1500RPM with 2 alternators if I can. I think I can get away with 1 alternator but 2 would be nice. Top speed is 2800RPM.
I would love to have a lister type but handling 750lbs is out of the question. The 130lbs my little engine weighs is bad enough and at the edge of my capacity.
Brian

[Chris Olson]

Ralph,
I would love to have a lister type but handling 750lbs is out of the question. The 130lbs my little engine weighs is bad enough and at the edge of my capacity.
Brian

This is kind of an old thread. But since last winter we put in a new Xantrex 120/240 volt inverter. So to use the auto gen start and energy management features in the inverter we bought a Generac standby generator. This is the unit we purchased:
http://www.generac.com/Residential/EcoGen_Series/Product/6kW/

It is very, very quiet running. My wind turbine makes more noise in a 15-20 mph wind than the generator does when standing right alongside it. It burns roughly .8 gallons of LP gas/hr at 3kW load, and we got 400 gallons of LP for $1.48/gal, although the current price is $1.99. But LP is still cheaper/BTU than gasoline or diesel fuel.

We've only put about 9 hours on it since we got it, but I am very happy with it.
--
Chris