SOLAR or GENERATOR? That is the question for Boondockers...

[idroba]

Thats good to know, thanks for the comeback.

[PharmGeek]

How much can stock converter interstate batteries fully charged last you in 30-40 degree overnight temps dry camping (40-50 during day) keeping thermostat on 65 furnace? And running generator say a couple hours a day to charge those batteries?

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[AirsDream]

About five years ago, I had Lewster install two 160 watt (or thereabouts) solar panels on my roof with an MPPT charge controller, high quality heavy cabling, and 3 AGM Lifeline batteries of about 110 amp hour capacity each. (If you're considering solar, I think that the received wisdom is that AGMs have less internal resistance, and so take charge current easier / faster, and you don't want to waste any of that power. They're expensive, but if you treat them right, they last a long time and are useful.) I also bought a Yamaha tri fuel 2400 watt inverter generator.

The big issue for me is that I wasted a lot of money on the Yamaha. It's a nice generator, starts easy and runs quiet - and I used to haul it around everywhere with me in the back of the tv. One long trip to Alaska and back ... I was SURE it would be rainy / cloudy enough of the time that I 'd need to use it to charge up the batteries from time to time, 'cause I almost NEVER stay in hookup campgrounds, always preferring to boondock. But though I did have a bunch of rainy days, etc. (you just get those in Alaska), I still always got enough light that I was always fully charged up by 10 a.m. or so. I never once started the generator. On that one trip alone, I hauled it and its fuel for more than 11,000 miles for nothing. And that's the thing: all-in, I just never use the Yamaha at all, ever, except maybe a time or two to run an air compressor when I'm using air tools on something or to run a carpet steam cleaner machine when I'm cleaning carpet or furniture in the trailer. Now I use it out in the barn occasionally to power up bigger tools for e.g. tractor maintenance. I got it with an hour meter, and after five years or so, I think I have about 25 hours on it.

But the solar panels just sit up there on the roof and make electricity without any noise, smell, fire hazard, fuel, care, or attention ... other than a once or twice a year hose-down to make sure they don't have bird dung or leaves or too much dirt on them. They clearly are all I need. Having said that, I should note that I took down my amp-hour usage quite a bit: a.) I replaced all my light bulbs with LEDs; b.) threw away my microwave; c.) brew my coffee via Melitta cone; d.) use only a 12v television and only very occasionally. So fundamentally, I power the house systems (including lights, controllers for fridge and water heater, vent fans, water pump, etc.) and a stereo and laptop and a few random chargers for flashlights, computer printer, phone, etc. And I cool with Fantastic Vent fan and a Fantastic Endless Breeze fan. Plenty for me, but others' mileage may vary. I just never run out of electricity. For me, the stay-limiting factor is always water capacity, and I can always manage to get ten days or more on the meager 46 gallons that I carry onboard (sometimes I "cheat" and take along a six gallon jug to supplement the trailer's tankage).

If you boondock a lot in the Pacific Northwest and stay in dense forest, you might need a generator. And if you need your electric blanket, coffee maker, skillet, microwave, blender, espresso machine, etc., then you also probably would benefit. Wanna' run an air conditioner? See Lewster's comments above - you probably will want some sort of generator.

But I like the quiet and freedom from hassle. I suppose I'll keep the Yamaha, but it stays home in the barn.

[idroba]

Originally Posted by PharmGeek

How much can stock converter interstate batteries fully charged last you in 30-40 degree overnight temps dry camping (40-50 during day) keeping thermostat on 65 furnace? And running generator say a couple hours a day to charge those batteries?

No simple answer to your question but here are some things to think about:

The stock batteries are about 75 amp hours each, 150 amp hours total. An amp hour is what it sounds like, a one amp load for one hour.

In general you do not want to discharge your batteries more than 50 to 60 % of capacity. Lets use 50%

So, your two batteries would then have a capacity of 150 amp hours /2 or 75 amp hours. This is assuming they were fully charged to begin with, and were in excellent condition.

You will always have some loads other than the furnace fan. The refrigerator takes 0.35 to 0.75 amps per hour, or in 24 hours 8.4 to 18 amp hours. Some water heater use... the water heater takes about .75 amps for each hour the burner is on. Lets say it runs 2 hours a day... that is 1.5 amp hours more. Water pump might take 4 amps, and lets say it runs 15 minutes a day, so one amp hour total. Lights are a big variable but lets say they are LED and the ones you have on take 1.5 amps for 4 hours a day, that is 6 amp hours more.


So, 8.4 to 18 + 1.5 + 1 + 6 = 16.9 to 24.5 amp hours for a day for "stuff".

Subtract that from the 75 you have available, you have 75-16.9 to 24.5 = 58.1 to 50.5 amp hours for the furnace to use.

The furnace in my 20' FC is a direct vent one, and is small, takes 3 to 3.65 amps while running. Your 30' has a much larger furnace, I expect it takes 6 amps at least maybe 7.

So for every hour the furnace fan is on, you take 6 to 7 amp hours from the batteries. Lets say the furnace runs 25% of the time, that is then 1.5 to 1.75 amp hours per hour average. 24 hours x 1.5 ( or 1.75) is 36 to 42 amp hours a day.

So, with careful use of other things you might have a day and a half of run time on fully charged batteries, not using them more than 50% of capacity.

Charging is another issue. The original converter/charger is not really very good at recharging. I would GUESS that it might charge at a rate of 20 amps on average, or 2 hours would put 40 amp hours back into the batteries. Remember you had a draw down possibility of 75 amp hours max, with fully charged batteries. And in 2 hours you might put 40 back in.

See, ask a question, get a production.

Not a simple thing to answer, and I took out a lot of the variables already. They can come back and bite you.

[lewster]

Well done!


Lew Farber
RVIA/RVDA Nationally Certified Master Tech
Master Tech Energy Systems, Inc.
AM Solar Certified Installation Center
Lifeline Batteries**Magnum Inverters
541-490-6357

[PharmGeek]

Thanks for the feedback

Is charging via converter with generator most efficient way ?

I'll simply have to see how real life goes

For summer here AC is needed and my boondocking plans will not restrict generator use

But spring - fall - and perhaps winter at some parks I think limit gen run time so I guess I'll have to see

This winter I am going to dry camp in back yard just to get a feel for how it plays out more or less


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[PharmGeek]

Originally Posted by AirsDream

About five years ago, I had Lewster install two 160 watt (or thereabouts) solar panels on my roof with an MPPT charge controller, high quality heavy cabling, and 3 AGM Lifeline batteries of about 110 amp hour capacity each. (If you're considering solar, I think that the received wisdom is that AGMs have less internal resistance, and so take charge current easier / faster, and you don't want to waste any of that power. They're expensive, but if you treat them right, they last a long time and are useful.) I also bought a Yamaha tri fuel 2400 watt inverter generator.



The big issue for me is that I wasted a lot of money on the Yamaha. It's a nice generator, starts easy and runs quiet - and I used to haul it around everywhere with me in the back of the tv. One long trip to Alaska and back ... I was SURE it would be rainy / cloudy enough of the time that I 'd need to use it to charge up the batteries from time to time, 'cause I almost NEVER stay in hookup campgrounds, always preferring to boondock. But though I did have a bunch of rainy days, etc. (you just get those in Alaska), I still always got enough light that I was always fully charged up by 10 a.m. or so. I never once started the generator. On that one trip alone, I hauled it and its fuel for more than 11,000 miles for nothing. And that's the thing: all-in, I just never use the Yamaha at all, ever, except maybe a time or two to run an air compressor when I'm using air tools on something or to run a carpet steam cleaner machine when I'm cleaning carpet or furniture in the trailer. Now I use it out in the barn occasionally to power up bigger tools for e.g. tractor maintenance. I got it with an hour meter, and after five years or so, I think I have about 25 hours on it.



But the solar panels just sit up there on the roof and make electricity without any noise, smell, fire hazard, fuel, care, or attention ... other than a once or twice a year hose-down to make sure they don't have bird dung or leaves or too much dirt on them. They clearly are all I need. Having said that, I should note that I took down my amp-hour usage quite a bit: a.) I replaced all my light bulbs with LEDs; b.) threw away my microwave; c.) brew my coffee via Melitta cone; d.) use only a 12v television and only very occasionally. So fundamentally, I power the house systems (including lights, controllers for fridge and water heater, vent fans, water pump, etc.) and a stereo and laptop and a few random chargers for flashlights, computer printer, phone, etc. And I cool with Fantastic Vent fan and a Fantastic Endless Breeze fan. Plenty for me, but others' mileage may vary. I just never run out of electricity. For me, the stay-limiting factor is always water capacity, and I can always manage to get ten days or more on the meager 46 gallons that I carry onboard (sometimes I "cheat" and take along a six gallon jug to supplement the trailer's tankage).



If you boondock a lot in the Pacific Northwest and stay in dense forest, you might need a generator. And if you need your electric blanket, coffee maker, skillet, microwave, blender, espresso machine, etc., then you also probably would benefit. Wanna' run an air conditioner? See Lewster's comments above - you probably will want some sort of generator.



But I like the quiet and freedom from hassle. I suppose I'll keep the Yamaha, but it stays home in the barn.

That is impressive - very cool


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[idroba]

Yes, running the generator to operate the converter/charger will give you the best results. Most generator charge circuits are unregulated, and are only in the 8 amp range.

And yes, do some testing on your own which will give you the best feeling for the situations you face. And to me, it is fun to do that kind of tests.

[PharmGeek]

I agree - love tinkering


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[lewster]

Originally Posted by PharmGeek

Thanks for the feedback

Is charging via converter with generator most efficient way ?

I'll simply have to see how real life goes

For summer here AC is needed and my boondocking plans will not restrict generator use

But spring - fall - and perhaps winter at some parks I think limit gen run time so I guess I'll have to see

This winter I am going to dry camp in back yard just to get a feel for how it plays out more or less


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Actually, the most efficient way to charge your batteries properly is with a programmable 3 or 4 stage charger that has full temperature compensation and is adjustable for type of battery (charging voltage profile) and size of the battery bank (absorption charge duration).

There are presently no RVC converters that can do this. You will need a Magnum inverter/charger or similar quality unit do get this done right.

[mefly2]

We started with no solar and one Eu2000 ... then came a larger trailer with a larger AC unit and the 2000 was not adequate. So, of course we opted for the companion ...wish that we would have looked at the EU3000is right away and saved some $$. We have a larger trailer yet again *equipped with solar* but where we boondock, there is no power available and cooler climates need to run the furnace more ...drawing down the AGMs.

So, almost every morning we fire up the EU3000iS (with electric start) microwave some bacon, heat some water, and charge the batts. We are long season campers from winter dry camping through spring and summer back to winter. It is great to have the solar, but I would not go without the generator. We followed Ray's initial analysis when we bought the first EU.

With Lew's suggestion, we plan to change out the converter and add two more AGMs ... for without storage capacity, much of the solar capacity is wasted. Dead Winter project time.

[JamuJoe]

Are you seeking peace and quiet or hauling the complexities and noise of mechanized civilization to a boondocking site?
That is the real question. I seek the peace and quiet and my answer is solar. No noise, no hauling gasoline. We do on't go boondocking to watch television. We sleep very comfortably in our Airstream. Yet, I do own a Yamaha 2400is. Just prefer not to use it or carry it.

Safe Travels,
JamuJoe


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[gypsydad]

Originally Posted by idroba

The quick disconnect may not have the proper pressure to operate a propane generator. Just a heads up to check before you purchase.

I was told at dealer it was fine....but thanks for the heads up. In the end, looks like solar is fine in cooler weather for boon docking for most of us, not factoring a week long snow in; but to be safe, a generator can be a "good safe backup plan" for extreme cold and southern summer camp outs...I think the generator from Costco (Yamaha engine) should work fine. I have a new Honeywell 2000 I purchased 4 years ago at Home Depot that is light weight; I will look into a propane conversion or sell it and get the tri-fuel model form Yamaha perhaps. Weight is important overall, and don't want to carry extra gas for this if not needed. May increase solar panels...not sure if portable or permanent...right now, 80W seems to work for our needs.. Summary for me is, solar most of the time in proper climate...light weight, propane generator as a backup, when you are not sure of weather....happy travels...

[TouringDan]

When I started boondocking about 3 years ago I already had a 1,000 watt Honda genny that I have had for the last 10 years. Btw, I don't think that there is any difference between my 10 year old Honda genny and a new one. For what it is worth, the genny is quiet, fuel efficient and very reliable and the best part is that I really hardly ever use it.

When I started boondocking, step one was to go to two golf cart batteries. My plan was then to install a 1,500 watt inverter so I could use the microwave, coffee pot, toaster and my wife's hair dryer. Then I was going to install two more batteries because I had room in the rear of my Tradewind. Well, I never got past step one (installation of two gc batteries) because I did not need to. As AirsDream mentioned in his post (#43), I got a lot more frugal in my use of the batteries. I installed LED lights, don't need a microwave, heat coffee on the stove and start up the genny if my wife is with me and we need toast and the hair dryer. Typically now, we start out with full batteries at about 13 volts. A typical boondocking campout is usually about 4 days and we usually are only down to 12.7 or 12.8 volts. Battery usage is only for the water pump, lights, some efficient fan usage as needed, some tv (12v), some cell phone recharge and that is about it. We don't seem to have any parasitic loads for the fridge as we have a new fridge, but it uses old technology, ie. only uses battery power for lighting the pilot initially. If we need to use the furnace the battery voltage drops lower than 12.8, but for occasional use we still don't need to start up the genny to operate the furnace.

Btw, I don't have a Tri-metric installed yet, only my battery minder, so I can only read battery voltages, but I will be installing a Tri-metric, then I will be able to determine the amperage that all the equipment requires.

I still carry my genny with me, just in case we need it (kind of like an insurance policy) or heaven forbid that it is hot enough that I have to install my 5,000 btu/hr AC unit, but generally it just sits in the truck bed.

My experience has been that it is possible to boondock for 4 or 5 days if you have adequate battery power (like two gc batteries) and are very frugal with your use of the battery power without needing either a genny or solar. My recommendation is to upgrade your batteries and reduce your battery consumption first and then decide about whether you want a genny, solar or both.

Dan

[Ray Eklund]

Our 23 foot 2006 Safari came with a small solar panel. Really small and I am sure someone knows what the capacity is for that year. It served us well. After ten days or more our voltage would be getting below 11.0 volts in the evenings and during the day is showed a 100% charging. Had it been a larger solar panel, or a pair... we probably could get by with just the solar with our conservative use of batteries.

Our new 2014 did not come with Solar. This creates the cost versus practicality of purchasing a generator and/or solar. I already discussed my step by step thoughts when the generator was chosen. This still does not discard the solar option as it worked so well with our limited power needs in our back country off the grid camping. Cold weather... we would be... screwed. But Spring and Summer warm weather... our small Solar worked as well as one could expect.

New Airstreams on the dealer's lot must all have one or two HDTV's. A microwave. Lots of power outlets for 110volt. We could have done without the microwave, which would have eliminated the fan to vent the Dometic refrigerator. Sure, we could have ordered one without the microwave... but here this 25 footer was sitting and other than the microwave... it was more than anyone could ask for... and we bought it. Never a regret.

Having a "factory solar package" would have made the generator optional. Without a solar package, it made the generator necessary. At least the LED lights are brilliant white and told, they consume very little compared to earlier lighting systems. We still use our power like misers.

Having one or two HDTV's while off the grid makes them worthless. As worthless as the microwave was in our 23 footer that we removed and used the space to store paper plates, cups and napkins. After being camped at the edge of the Big Horn Mountains near Buffalo, Wyoming to charge the batteries, I tested out the television... had reception. Never in my Airstream experience did I ever imagine I could be out in nowhere and watch the news, weather or feel connected whenever I wanted. As you know, there is no newspaper tossed in front of your trailer at some GPS grid "address". By having the generator it was our reward for 8 years with minimal furnace use and doubling up the sleeping bag covers on those below freezing mountain "Summer Evenings".

The most hardened game hunters now have a generator available at their remote campsite and we are no different. Technology is great, but not necessary or required. Is Solar part of our future... next year will provide that decision. Will the total cost of the hardware, installation and additional cost for batteries be worth the investment? Do we have to consider where we are camped to catch the most sunlight "arc" while others are camped in the cooler shade of the forest with their generator purring along? This is not an environmental issue. It is an issue of practicality. Being frugal individuals, myself and my wife, the cost benefit of having both options will be considered. As a rancher thinking of buying a neighboring ranch said to me once... "the cost of the additional pasture just does not... pencil". Sometimes one person's great idea just is not financially responsible. This will not be, Solar that is, purchased on a whim. It had better pay for itself and be worth the cost.

[Gringo]

We've just spent four days out away from any hookups, boondocking in the 27FB for the first time. I changed to two GR 27 batts and bought a Zamp 200 watt portable solar setup. Based upon this limited experience, I am thinking about buying a Honda 1000i generator. And yeah, I know about the 2000i. I have one on the boat. But we don't think we need the 2000. We don't care about the microwave, nor the air conditioner. We would like some redundancy for the obvious reasons. Mainly shade due to location or weather or high demand due to furnace operation. Simply put, I don't want to get stuck in another two day snowstorm in an Airstream with no power. Ever again. The 1000 watt Honda is lighter, quieter, and runs for 8 hours on a half gallon of gasoline. I'm thinking of starting with one of those, instead of buying a 2000.

Does anyone know if you can hook a 1000i Honda to a 2000i Companion?

[dkottum]

We don't use the a/c, microwave or a hair dryer when boon docking so our factory solar does a great job. If we ever need more power we will add solar. We have traveled with our Honda 2000i and gas can but like to keep travel light and simple so we don't take it along anymore.

[TinTin]

Gringo, not sure if the 1000 and 2000 can link together, suspect the answer is no.

My thoughts: while the 1000 would likely do fine for charging batteries, it is a little light for other possible applications (such as a 1500 watt heater, toaster).

[Chris C]

We have two Honda 2000 generators with the two-generator connector setup. In our trailer, we have a convection oven, flat-screen TV, air-conditioner and hair-dryer to run, often at the same time. No problem with the generators. Would I consider Solar?....................maybe if the majority of our camping were off grid, but (unfortunately) it's not.

[Nomad518]

Under the right conditions, solar would be nice to have. But, we don't have it on our '01 Safari and we dry camp 90% of the time mostly along the Northern CA coast where it's often foggy. I carried a Honda 1000 generator for years to keep the single battery charged up. But, I traded up to two Honda 2000 generators a couple of years ago. Total cost of the generators was about $2k (less if you deduct the sale of my old perfectly good Honda 1000). I considered the total cost of the two generators and weighed it against the cost of solar installation which can be pricey. Then, I also considered that with the two Honda 2000's, I could also run my AC which we have actually needed numerous times when dry camping. I couldn't do that with solar panels. I also can't disconnect solar panels from my AS and use them as an emergency power system at home, or to power tools and other stuff as needed. Most of the time, I only need to use a single generator for an hour in the morning and maybe an hour in the late afternoon to provide all the battery power we need. I plug the trailer directly into the generator so that the battery is charged with the onboard converter which I upgraded from the original. Another advantage to a generator...when you have noisy, inconsiderate, late-night partying campers in the site next door and they keep you up all night, even a really quiet generator like a Honda 2000 provides a nice way to return the favor when they're trying to sleep it off the next morning at 11:00 AM. You can't get that with solar panels.