Advice needed. Which genset for off grid?

Coug

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I'm going to agree to disagree. My stuff obviously comes from a different place than your stuff. No sense in writing novels that won't change anything in the end. This was supposed to help a guy decide how to homestead off grid, not the finer points of debatable physics. I yield.

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That is fine, but if you have a source for where this comes from I would actually like to see/read it, as it is contrary to everything I have ever heard.
All an engine does it turns heat energy into movement energy. In a diesel engine it turns it into rotating mass. I'm just not understanding how so much additional energy is used to power a nearly identical amount of rotating load simply by doubling the number of cylinders.
 

Jeepadict

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That is fine, but if you have a source for where this comes from I would actually like to see/read it, as it is contrary to everything I have ever heard.
All an engine does it turns heat energy into movement energy. In a diesel engine it turns it into rotating mass. I'm just not understanding how so much additional energy is used to power a nearly identical amount of rotating load simply by doubling the number of cylinders.
I start with the manufacturer's specs which guides me to a bit. Then the stuff you quoted has some variables that have nothing to do with the OP asking for help. Like I said, I yeild.

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155mm

Chief and Indian
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could be you need a DC charging generator to keep your batt bank up to level and continue using the inverter.
What he said 👆, why not just charge dc to dc, i know inverters have gotten better, but there is still energy lost converting.

there is a 5kw 24v diesel .... 952b
there is a 4.2kw 24v gasser
 

KTMGuy

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I have been to Alaska a couple times in the summer, this goes back to before the AlCan highway was paved! I drove a truck up there and I never had so many flat tires in my life and on that road you change your own. That was when I found out about Alaska's state bird, The huge freakin mosquitoes!!!! One distracts you by flying in front of you and his buddy comes up behind and grabs you and you better be hanging on to something or he will take you away!!!
It sounds like you have this thing pretty much figured out. I have just seen so many people try this over the many years I was involved with the outdoors and at least half of them failed due to underestimating nature. And advice given. Didn't want to see another.
Actually you could be talking about Indiana. Bad roads except for the new I-69 and flies and skeeters all over. My KTM windshield is a mess just from a short ride. Anchorage is about as modern a city you could hope for. Its also home to joint base Elmendorf - Richardson (JBER ). Lots of troops there. Im starting to get the feeling everyone thinks Alaska and living 15 miles from several towns is a survival exercise . I assure you its not! Ive been living in a solar rv for almost 3 years with no real complaints. I have heat, water, A/C, a shower (with hot water) and the best modification which was getting rid or the original rv toilet and getting a Natures Head composting unit. No more dumping. Solar power and generator power do the charging of the batteries to be converted to AC power. We use the same appliances as a grid tied home. Its not rocket science or voodoo. Theres plenty of tiny homes in the lower 48 that are off grid and use solar and/ or a genny for power.

Before the AlCan was paved? Buddy, your braver than me for that! But, boy what an adventure I bet! You have my respect for that.

Vince
 

KTMGuy

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That would put your 802a at 115% load, a tad high but nothing the generator can't handle.

Wouldn't the load go down as the batteries charge? If it does I'd say you're golden.
Thats not a firm number as I can make due anywhere from 40 to 60Amps. 60 would still be nice as I would have 2 - 30amp chargers in parallel. And yes, the load would steadily go down after the beginning surge. The batteries are Crown 6v 430A 930 Deep Cycle. Once I hit 90% charge it drops way down to a trickle charge and slowly gets to 100% (float mode) . Thats about 54v. This is a 48v battery bank.

Vince
 

KTMGuy

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Exactly. And running a 5 KW for any longer period, at 7.5 KW is asking a bit much. Everyone wants to load these sets to the max. Do you run your car at max RPM in 1st gear? Not long. If you plan a 5 KW load, and it spikes every now and then. No problem. Or 1-2 KW for short times, no problem.

You need to do a max possible load plan. Worst case plan. Then add about 4-5%. Then you can decide what you need. But right off hand, I would be leaning towards a 10 KW. But the plan is a must. Too little gen set, you are load managing. Do-able, but you can't sleep at the wheel. You have to MANAGE. When we were in the field, everyone and his dog hooked up "Just a coffee pot", "or just a TV". Well, before you know it, the set would kick off for over load. Reset, kick off. My cure was side cutters. I simply walked around cutting off plugs.

Too little load, waste fuel and wet stacking. Too little gen set, management.
Then that would be 60A as the upper limit. A little extra then about 63 amps. My 802 works fine with the RV and Im sure "can" work for the cabin, but at a longer charge time. But as you say, I dont want to run mad max all the time on the 802. Yes, we manage what we turn on and off and will continue to manage in the cabin. We dont plan on running a cruise ship type power load - just the essentials. The fridge and stove are gas. The biggest load will be the Splendide washer/dryer at 1300W. The Instant Pot is second at 1000W. Heat is a coal stove.

Vince
 

KTMGuy

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What he said 👆, why not just charge dc to dc, i know inverters have gotten better, but there is still energy lost converting.

there is a 5kw 24v diesel .... 952b
there is a 4.2kw 24v gasser
It sounds nice - If my battery bank was 24V. Its 48V. I could use a stepup transformer though, but we're adding more complexity to the equation. Theres marine step up/down transformers for boats and ships just for that purpose.

Vince
 

KTMGuy

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i wonder how reliable a wind turbine would be in that environment? could be to wet? i would ask bergey if they have any in alaska.
Wind power? Oh yes - very doable. I know someone who uses a 6kw turbine in Juneau and that place is right on the ocean - its been spinning for 3 years with no problem. I would need a massive steel pole to get above the birch trees that will surround the place as well as a huge cement foundation under the pole. Lots of cables need to be run on the pole. They have very high winds in the winter from the storms. Marine turbines would work well also but they only output 400w as Ive seen.

Vince
 
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Guyfang

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What he said 👆, why not just charge dc to dc, i know inverters have gotten better, but there is still energy lost converting.

there is a 5kw 24v diesel .... 952b
there is a 4.2kw 24v gasser
OOOOOOOOOOOH! I would not depend on a MEP-952B for long. They work well, when they work. But when they DONT work, oh baby.

The 4.2 gasser, well, only if the engine was upgraded to electronic Ignition. THEN you have a runner!
 

Guyfang

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Actually you could be talking about Indiana. Bad roads except for the new I-69 and flies and skeeters all over. My KTM windshield is a mess just from a short ride. Anchorage is about as modern a city you could hope for. Its also home to joint base Elmendorf - Richardson (JBER ). Lots of troops there. Im starting to get the feeling everyone thinks Alaska and living 15 miles from several towns is a survival exercise . I assure you its not! Ive been living in a solar rv for almost 3 years with no real complaints. I have heat, water, A/C, a shower (with hot water) and the best modification which was getting rid or the original rv toilet and getting a Natures Head composting unit. No more dumping. Solar power and generator power do the charging of the batteries to be converted to AC power. We use the same appliances as a grid tied home. Its not rocket science or voodoo. Theres plenty of tiny homes in the lower 48 that are off grid and use solar and/ or a genny for power.

Before the AlCan was paved? Buddy, your braver than me for that! But, boy what an adventure I bet! You have my respect for that.

Vince
EVERYONE I ever knew who was stationed up there loved it. It was the only assignment we had no hope of getting when we got out of WOC school. The branch manager told us, No Warrant rotates from Alaska. They die in place, and the replacement list is LONG!
 

KTMGuy

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Ah! Warrants! Love most of you guys. I have a Warrant 0-4 buddy (retired) that flew AH-1 Cobras in Desert Storm. He loved to tell people he was there to solve problems you didnt know you have in ways you dont understand. Seemed to be the unit mantra. Actually it fits all Warrants. ;)

Thats what my friends told me about JBER and rubbed it in any chance they got about Ft. Richardson. I've been through a few times, but never assigned.

OK - onward! I appreciate all the advice and comments you peoples have given me, and there was much to think about, but now I have made a choice and that choice will be to keep the 802a as backup and get a MEP-803a for the main generator. It checks all the boxes except the weight category - I see a trailer is also in my future. If memory serves, its the M116A3. The fuel capacity and per hour use is just fine and the output is good - more than good actually. I can scale up the battery chargers as needed to accommodate the genny. The chargers are cheap enough whereas the generator is not. Actually, the 803a is cheap compared to a commercial unit like the Generac, Cummins, or other brands - new or used.

Vince
 

Coug

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*snip*

OK - onward! I appreciate all the advice and comments you peoples have given me, and there was much to think about, but now I have made a choice and that choice will be to keep the 802a as backup and get a MEP-803a for the main generator. It checks all the boxes except the weight category - I see a trailer is also in my future. If memory serves, its the M116A3. The fuel capacity and per hour use is just fine and the output is good - more than good actually. I can scale up the battery chargers as needed to accommodate the genny. The chargers are cheap enough whereas the generator is not. Actually, the 803a is cheap compared to a commercial unit like the Generac, Cummins, or other brands - new or used.

Vince
Yeah, and good luck getting any warranty support out there in the middle of nowhere.
All the modern stuff has so many electronics that they are a pain in the butt to do any work on without the correct manuals and in some cases software, not to mention you're unlikely to even find them in this size range.
At least with the military gens you have all the manuals available and this forum to help out.
 

KTMGuy

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If noise isn't as big of a concern then the MEP-003 is also a good choice. Being an air cooled diesel there is even less to go wrong with it than the 80X series.
Oh? Let me look and see. Noise is not an issue if the noise tells me its still running. Thanks for the advice!

Ok - looking at a video, it seems the difference between it and the 803 is the 003 has no enclosure - correct? And noisy of course, but its whisper quiet compared
to standing near a 155 going off.

Vince
 
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KTMGuy

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Yeah, and good luck getting any warranty support out there in the middle of nowhere.
All the modern stuff has so many electronics that they are a pain in the butt to do any work on without the correct manuals and in some cases software, not to mention you're unlikely to even find them in this size range.
At least with the military gens you have all the manuals available and this forum to help out.
And that ladies and gents is what its all about! Warranty support looks good on paper, but when you need something expensive like a genset fixed like right now, it probably wont happen especially in bad weather. I've been around military generators a lot when I was in, but always took them for granted because they worked and if they didnt, there was someone turning wrenches on it fairly fast. Wish I would have paid more attention.

I know that being in the RV crowd, that the smaller Honda's, Champions and other brands are NOT field serviceable. This is why I got the 802 - It can be repaired at home if needed. So far it still runs like new and I just do careful maintenance. I know people that sneer at my big to them diesel, but I've seen their gas gens self destruct because they cant do anymore than put gas in and change the oil occasionally. I cant count how many times I've rolled my stinky diesel 802 to charge someones batteries because their expensive gas gen died and theres no parts to fix it or someone to come out within a reasonable time to repair it.

I love my diesel!

Vince
 

Guyfang

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Oh? Let me look and see. Noise is not an issue if the noise tells me its still running. Thanks for the advice!

Ok - looking at a video, it seems the difference between it and the 803 is the 003 has no enclosure - correct? And noisy of course, but its whisper quiet compared
to standing near a 155 going off.

Vince
The sound of a 155, is something everyone needs to hear at least once in the remaining time on this earth.
 

snowtrac nome

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im living that way now in alaska i live up by the arctic circle where daylight is even less. my power is off an 8k lister 2 cyl built in the 70's im currently living in an atco trailer while i build the new house. here is what i have learned. my trailer is heated with a toyo lazer 73 i also have a wood stove for heat while we are there. trees are few and far between i burn pallets. my consumption right now with temps above 0 is 15 gallons a month in the toyo and 5 per week in the generator i have 2 5 k liquid cooled kubota generators i'm planning on changing out to be prime power because i just cant get enough load on the lister to prevent wet stacking. i would use teh mill spec gen as a backup but you should look into a commercial generator you can get parts for fast for prime power.
 
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