Running stove on generator?

[zrtmatos]

It's about time somebody gave the correct answer for this thread.. ;-) .. salt or no salt?!

What he said!

 

[Deromax]

Lot of misconceptions about power here!

1) The power utility supplies a sinusoidal wave form with minimal distortion, ie "pure", produced by alternators. (first pic)

2) A conventionnal home generator also use an alternator but it may produce a slightly less than perfect sine wave, ie with a slight but mostly irrelevant distortion. (second pic)

3) Several decades ago, the first inverters produced a square wave, because it was the simplest thing to do with the then available tech. They made motors humm like mad and power supplies to overheat, so were eventually phased out. (pic 3)

4) In the last 15 years or so, inverters began to use a slightly less square waveform. Despite the sharp edged looking waveform, this will powers a lot of things without much issue, including "delicate electronics". (pic 4)

5) With advancing in tech, is became feasibly at affordable cost to manufacture a pure sine wave inverter, so they did. Those are still more expensive than modified sine wave however. Hence the two kind are still sold to this day for differents price points.

6) Gennies manufacturers began to use inverters in their products as it allows them to throttle down or even iddle with a slight load, something a traditionnal genny can't do.

What kind of inverter is part of your "inverter genny" is a matter of what the manufacturer decided to use. They are usually eager to promote the fact that they use pure since wave in their promo material. Honda and Yamaha have well known such products. A cheaper inverter-genny that doesn't spell it clearly might be suspect in this regard. Maybe the cheap Chineese no-name units.

So, everything pure sine wave and conventionnal gennies should powers a pellet stove OK as is, with no need for power conditionners, surge protectors or additionnal inverters inbetween. In the case of a modified sine-wave, I would say, try it, it might just work!

 

[IHATEPROPANE]

Lot of misconceptions about power here!

1) The power utility supplies a sinusoidal wave form with minimal distortion, ie "pure", produced by alternators. (first pic)

2) A conventionnal home generator also use an alternator but it may produce a slightly less than perfect sine wave, ie with a slight but mostly irrelevant distortion. (second pic)

3) Several decades ago, the first inverters produced a square wave, because it was the simplest thing to do with the then available tech. They made motors humm like mad and power supplies to overheat, so were eventually phased out. (pic 3)

4) In the last 15 years or so, inverters began to use a slightly less square waveform. Despite the sharp edged looking waveform, this will powers a lot of things without much issue, including "delicate electronics". (pic 4)

5) With advancing in tech, is became feasibly at affordable cost to manufacture a pure sine wave inverter, so they did. Those are still more expensive than modified sine wave however. Hence the two kind are still sold to this day for differents price points.

6) Gennies manufacturers began to use inverters in their products as it allows them to throttle down or even iddle with a slight load, something a traditionnal genny can't do.

What kind of inverter is part of your "inverter genny" is a matter of what the manufacturer decided to use. They are usually eager to promote the fact that they use pure since wave in their promo material. Honda and Yamaha have well know such products. A cheaper inverter-genny that doesn't spell it clearly might be suspect in this regard. Maybe the cheap Chineese no-name units.

So, everything pure sine wave and conventionnal gennies should powers a pellet stove OK as is, with no need for power conditionners, surge protectors or additionnal inverters inbetween. In the case of a modified sine-wave, I would say, try it, it might just work!

Much more articulate than what I was trying to say.

 

[gfreek]

Good explanation..

 

[2biker]

Ok...so if you are running a moderate size generator (like 5,6, or 7k), why use pellets? I run a 7k during outages. And if I'm making that kind of power, I take advantage of it and run electric space heaters. 3 heaters can keep the house comfortable during the day. I shut everything down at 11 pm and start up again at 6am to get hot water for showers. If I'm paying for generator gas, you might as well get your money's worth out of it.

 

[novah]

<snip>5) With advancing in tech, is became feasibly at affordable cost to manufacture a pure sine wave inverter, so they did. Those are still more expensive than modified sine wave however. Hence the two kind are still sold to this day for differents price points.</snip>

If you have a generator without an on board inverter, can you run a pure sine wave inverter off a deep cycle battery for the delicate electronics with a battery charger powered by the generator to keep the battery fully charged?

 

[Bassmantweed]

Ok...so if you are running a moderate size generator (like 5,6, or 7k), why use pellets? I run a 7k during outages. And if I'm making that kind of power, I take advantage of it and run electric space heaters. 3 heaters can keep the house comfortable during the day. I shut everything down at 11 pm and start up again at 6am to get hot water for showers. If I'm paying for generator gas, you might as well get your money's worth out of it.

This makes no sense to me. But to each their own.

 

[mchasal]

If you have a generator without an on board inverter, can you run a pure sine wave inverter off a deep cycle battery for the delicate electronics with a battery charger powered by the generator to keep the battery fully charged?

Though it sounds pretty inefficient due to all the conversions (AC from the generator, to DC in the charger, to the battery, then back to AC from the inverter) what you're describing sounds like an "Online UPS" https://en.wikipedia.org/wiki/Uninterruptible_power_supply#Online.2Fdouble-conversion

I think it would work as you describe and if the goal is just to get sine wave power from the generator in an emergency, electrical efficiency probably isn't a big concern. However, you will need to make sure the battery charger is capable of keeping up with the draw from the load or you will eventually run down the battery. At that point I suppose the charger will be trying to run the load directly and will not be able to do so. Not sure what happens in that case, but it's probably not great. Also, make sure the battery has adequate ventilation.

I believe you could even eliminate the battery and charger from the loop and just run a 12v ac-dc power supply of sufficient capacity from the generator directly to the inverter. Again, will have some inefficiencies, but should achieve the goal. Of course, without the battery you won't have any UPS feature that will keep the stove running if the generator stops.

Unless I'm wrong, which I'm sure someone will point out soon if so.

 

[BrotherBart]

All of those six to seven day power outages running on the cheap generator finally killed my refrigerator. After 29.5 years.

Only thing that has ever crapped out. Including the server farm in the basement before I shut it down and retired.

 

[novah]

I thought the UPS was a short term device - maybe a hour or two - and I am looking for a safe way to run electronics for the duration of the outage. Am I mis-understanding what a UPS is?

 

[alternativeheat]

About the longest the power goes out around here is 3 days and that's on a pretty major outage. I guess we are close enough to the main line power coming on cape that they get to us fairly soon. Most outages are a couple of hours otherwise. We bought the 5.5K generator so the main heat supply in the house could run in power outages because my 90 YO father in law lived in the attached apartment and he needed nearly 24 hour care, never mind freezing. So long story short, I don't keep the pellet stove going in power outages but run the central heating system, most appliances and several lights and outlets in the house and apartment.. I even run my coffee maker and the care giver girls used to run the microwave over in the apartment when the old man was in there. Having that generator really takes the curse off of threatening weather, I'm really not concerned if I get pellet stove heat or not for that short of a time but if I had no other means of heat I would just try the generator first , it runs everything else in the house and many have digital displays, LCDs etc.

 

[2biker]

Excellent post, Alternativeheat. Can't understand why people in this forum enjoy paying for generator gas for the opportunity to burn pellets during an extended outage. Well.... if you like living in one room with one heat source...and don't mind spending the extra $. Then God bless you. But if you produce the extra electricity...it is use it or loose it! Take full advantage of that generator and spread the heat to other areas of the house with space heaters. To me, It's like free heat.

 

[bogieb]

Ok...so if you are running a moderate size generator (like 5,6, or 7k), why use pellets? I run a 7k during outages. And if I'm making that kind of power, I take advantage of it and run electric space heaters. 3 heaters can keep the house comfortable during the day. I shut everything down at 11 pm and start up again at 6am to get hot water for showers. If I'm paying for generator gas, you might as well get your money's worth out of it.

One reason I can think of is that my pellet stove has cast iron cover plates. When the stove shuts down, it will radiate heat for a long time. So, if I have to shut down the generator at night (for safety purposes), and it is -13 (and possibly windy to boot), the house can get mighty cold mighty quickly unless you have a big heat sink that will share its warmth when the surroundings cool down.

 

[mchasal]

To me, It's like free heat.

I haven't measured it, and maybe your generator is different than mine, but mine uses more fuel running a higher load on the generator than a lower one. So it would cost me more in fuel to run a few thousand watts of space heaters than 100 watts of the pellet stove. I have no idea which one would actually be cheaper to run once you factor the pellet cost in, but the heat from my generator wouldn't be free.

 

[mchasal]

I thought the UPS was a short term device - maybe a hour or two - and I am looking for a safe way to run electronics for the duration of the outage. Am I mis-understanding what a UPS is?

A UPS is always supplying power to the load, so in that regard it is a long term, constant supply device. The only short term part is when the utility power is lost it will keep supplying power from the battery until that is depleted. So when you take a UPS and plug it into a generator, the generator becomes the utility and it will continue to run off that power. Though I've read that some UPS units won't run properly off some generators.

The setup you describe is basically an online/double conversion UPS as described in that wikipedia link. The power for the load is always coming from the battery and as long as the utility power is there, the battery is being recharged. As long as utility power of some sort is entering the input, it will run "forever" (barring equipment failure etc) I'm sure the commercial models are a bit more advanced, but that's the basic idea. It gives you the advantage that you can still provide power to the load while you refuel or service the generator for as long as the battery will allow.

 

[adam6979]

I'd sure like you (or anyone else foir that matter)explain to me how to maintain cattle water tanks from freezing in sub zero weather or how to power a machine and fabrication shoip or how to provide light vith a pellet stove.... obviously, you can't. I heat my home with pellets and/or corn and have for years but that has little to do with the rest of the operation, in fact, 17KW in a power outage, in the winter is marginal at best, especially when the shop is powered up. Been considering a 25KW Diesel powered standby with 3 phase 440 output..

We don't live in a house on a lot, this is a working cattle farm and enterprise with all the things (electrical powered that go with it). My typical utility bill is around 350-400 bucks monthly in the winter, depending on how cold it gets and electrical load....

If you have a viable alternative, I'd like to know, if not, don't deride me.

Back to regular programming....

I agree - someday we will have a higher generator. Probably a 30k diesel military generator, of course wired to automatically switch on/off in event of power loss. We have a large setup too and yes generator is the way to go. When everyone else is in the dark... it'll make you smile to go on with life like it never happened.

 

[SidecarFlip]

I agree - someday we will have a higher generator. Probably a 30k diesel military generator, of course wired to automatically switch on/off in event of power loss. We have a large setup too and yes generator is the way to go. When everyone else is in the dark... it'll make you smile to go on with life like it never happened.

Sent you a PM......

 

[Deromax]

But if you produce the extra electricity...it is use it or loose it! Take full advantage of that generator and spread the heat to other areas of the house with space heaters. To me, It's like free heat.

Not exactly. There is no free lunch. If you consume more electricity, your genny will consume more fuel, which is highly taxed car gasoline. Heating with electric on a genny is about the most expensive way to heat, and it will make the genny work much harder.

 

[BrotherBart]

But you can apply for a Federal, and in most states, refund or credit for off road use of the gasoline. I file for it every year. The 25 gallons I purchase every October either gets used in the generators in outages or into the garden tractor starting the following Spring.

"To claim a credit for the federal tax, taxpayers file with their tax return Form 4136,Credit for Federal Tax Paid on Fuels. If the expense for purchasing the fuel (including the tax) is deducted as a business expense, the credit or refund must be included in gross income by the taxpayer. Taxpayers with at least $750 in credit or refund due in a quarter or any number of quarters within a year may file for a refund with Schedule 1 of Form 8849, Claim for Refund of Excise Taxes."

 

[2biker]

You don't appreciate electricity until you have none. You don't buy a generator with the intention of running it at half load. True, here in southwestern CT, we don't get the extreme cold as our friends to the north. So spending $30 or $40 per day for gas during an outage is a lot cheaper then my friends who flee to a hotel. And to run a generator at a reduce load....what are you going to save? Two maybe three gallons a day? Who wants to spend their power outages living in one room around one heat source? If you take your time and execute your plan, an outage should be nothing more then the inconvenient sound of a running generator.

 

[alternativeheat]

You don't appreciate electricity until you have none. You don't buy a generator with the intention of running it at half load. True, here in southwestern CT, we don't get the extreme cold as our friends to the north. So spending $30 or $40 per day for gas during an outage is a lot cheaper then my friends who flee to a hotel. And to run a generator at a reduce load....what are you going to save? Two maybe three gallons a day? Who wants to spend their power outages living in one room around one heat source? If you take your time and execute your plan, an outage should be nothing more then the inconvenient sound of a running generator.

I very much appreciate that I have central heating, hot water, a few outlets, our tenants apartment, two rooms lit, downstairs bath lit and powered up . When a storm hits that is mighty comfortable living compared with a 36 deg dark house for three or four days, even if we have oil lamps going in some other areas of the hosue... I could put more circuits online actually , as the gen runs well below half output but I really don't want to pay for a larger transfer switch.. As to gas, it does all that on less than 10 gal a day of fuel. But it is not a standby gen, it's a portable. Shut it down every 10 hours or so, check the oil refill the gas. I am not complaining, a lot of people, in fact most out this way have no generator. i think us and our tenant live pretty comfortably through a winter storm.

 

[velvetfoot]

In the last big storm, a number of gas stations didn't have any gas to sell because of delivery problems. Plenty of others didn't have backup generation, so gas wasn't available. That's my reason for economizing on gas during an outage.

 

[mchasal]

You don't appreciate electricity until you have none. You don't buy a generator with the intention of running it at half load. True, here in southwestern CT, we don't get the extreme cold as our friends to the north. So spending $30 or $40 per day for gas during an outage is a lot cheaper then my friends who flee to a hotel. And to run a generator at a reduce load....what are you going to save? Two maybe three gallons a day? Who wants to spend their power outages living in one room around one heat source? If you take your time and execute your plan, an outage should be nothing more then the inconvenient sound of a running generator.

There's a whole spectrum between "fleeing to a hotel" and "not noticing the power's out except for the sound". It's great that you've decided to be in the latter category and have the equipment to support it, but many are happy to just keep the basics running for the few days a year that the power is out.

 

[F4jock]

Ya know, even though I understand the discussion it's making my head explode! About 25 years ago after the first extended power outage up here that left us with no utilities save for the phone, we picked up a propane-fired 4 cylinder Renault powered, 17.5 Kw Onan with 36 hours on it that was sitting in a farmer's field. We had it refurbished and added an auto-start transfer switch. Since that time it's run as much as eight days at a time powering the entire house including, for the last seven years, our Harman Accentra Insert with nary a hiccup. Although I appreciate the technical dissertations above I thus have no clue what all the fuss us about. Am I just lucky or has stove technology changed so much that a certain AC waveform is now necessary? I somehow can't see my rescued Onan as having an inverter conforming to any of the foregoing specifications.

 

[alternativeheat]

Ya know, even though I understand the discussion it's making my head explode! About 25 years ago after the first extended power outage up here that left us with no utilities save for the phone, we picked up a propane-fired 4 cylinder Renault powered, 17.5 Kw Onan with 36 hours on it that was sitting in a farmer's field. We had it refurbished and added an auto-start transfer switch. Since that time it's run as much as eight days at a time powering the entire house including, for the last seven years, our Harman Accentra Insert with nary a hiccup. Although I appreciate the technical dissertations above I thus have no clue what all the fuss us about. Am I just lucky or has stove technology changed so much that a certain AC waveform is now necessary? I somehow can't see my rescued Onan as having an inverter conforming to any of the foregoing specifications.

Good question. Some people say about that some new electronically controlled stoves recognize dirty power and shut down. I can't confirm this with my own rig because I have my Gen wired to run the oil heat . It's not worth the bother for me to find out either.