boondocking for the first time?

Mashmaster · 09-29-2021, 10:41 AM

I will be boondocking in the very near future (4 day trip). It is a Minnie Winnie 31C.

What can I run without running the generator? Fridge (on propane option), ceiling lights. Anything else? How long will it run the fridge? How much propane does the fridge take to run?

I have a built in generator, so I can run that if I really need the microwave or TV.

Does it make sense to install a 12v ceiling fan in the RV?

How much Solar would I need to run say a LCD TV? Would a portable unit work for that?

I am not quite ready to do a full blown solar system, as I am not sure if I will like boondocking.

Marine359 · 09-29-2021, 11:22 AM

You didn’t mention the size of your battery bank and what kind of batteries they are. Then you need to know what your daily power consumption will be on average. The only things that need ac power are the 110v outlets, the microwave and the roof A/C. Everything else runs on dc. Since you have an absorption fridge which can run off propane, you daily consumption can be very low unless you need to run the furnace. Most people with absorption fridge can get by with 25amp/hrs per day with no ac usage.

If you don’t know yet whether you will like boondocking, try it first with your existing setup and try to measure your consumption. If you must watch tv, you can buy a cheap 12v to 110v inverter brick for about $120, enough to run a small ac tv and some other small ac consumption. Or, For about $200 you can buy a small power station with dc and inverted ac output. I just bought one that has regulated 12v outlet, so I can run my cpap. One of these puppies can meet your boondocking needs for several days if you conserve.

12v ceiling vent fans are expensive. Suggest you try boondocking first with windows open, bathroom fan on if needed, and supplement with a cheap 12v usb fan, about $25 on Amazon.

Mashmaster · 09-29-2021, 11:28 AM

Thanks, I am not sure what batteries are in my RV.... I guess I should check that. I know there are two of them and they are fairly new. That is all I know.

powercat_ras · 09-29-2021, 11:34 AM

Propane use - if all you use propane for is cooking and the refrigerator, you will be able to go 1-2 months between tank refills.

For under $ 50 you can self install a battery shunt and battery monitor that will show exactly how much power you are using, so you can see your power consumption and % battery remaining. Your batteries will last a lot longer if you can track their % and never let to go below 1/3.

If you have 2 of the Winnebago OEM NAPA RV/marine batteries, using some lights, some use of ceiling fan, plus the base loads of the refrigerator, propane detector, and thermostat you likely can go about 4 days between 90% and 33 %.

If your 31C is older and does not already have LED lighting, you will want to change out the lights you use long periods of time to LED. LED uses less than 20% the power of filament light bulbs.

Battery Monitor

Marine359 · 09-29-2021, 11:35 AM

Quote:

Originally Posted by Mashmaster

Thanks, I am not sure what batteries are in my RV.... I guess I should check that. I know there are two of them and they are fairly new. That is all I know.

It will say on the side of the battery what kind they are. If they tell you how many CCA (cold cranking amps). They are Marine deep cycle, and usually can store from 35-50 amphrs. That’s enough for two days of conservation minded boondocking. If they are sealed and say AGM, they should show the number of rated amphrs. If they are AGM, you’re in really good shape, as they normally are 100amphrs each. If this is a used RV, you may want to call the prior owner to ask when they were installed, what kind they are, and whether they were kept on a battery minder.

Marine359 · 09-29-2021, 11:49 AM

If you have a multimeter measure the voltage across the battery terminals. The voltage range of a 12v marine deep cycle is about 1.5v. If you charge it fully, it will probably be at or near 12.7v. So, if you measure again after 24hrs of usage, you can calculate DoD (depth of discharge) which should never go below33% for this kind of battery.

Mashmaster · 09-29-2021, 12:01 PM

I have converted all the lights to LED's. I like the idea of the battery monitor but maybe I will get through this first weekend.

I will check the batteries in a couple of days when I get it out of storage. There is a receipt for the batteries if I remember correctly.

I like the idea of the portable battery station as a backup. Any recommendations on that? Seems like I can have that and charge it via solar panels in the future.

DavidM · 09-29-2021, 12:13 PM

Your batteries are probably Group 27s and typically each has a capacity of 70 Ahs or 140 total. But you should generally not discharge these batteries below 50% for best life, so realistically you have 70 Ahs usable.

With no TV watching, just lights at night, I use about 25 Ahs in 25 hours. So you can usually camp for 3 nights and stay above 50%.

Here is a simple and effective shunt based battery monitor. All you need in addition to the stuff in the package is a short jumper to allow the shunt to go in the negative battery cable. You can buy one at a marine or auto parts store.

See https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

Marine359 · 09-29-2021, 12:17 PM

Quote:

Originally Posted by Mashmaster

I have converted all the lights to LED's. I like the idea of the battery monitor but maybe I will get through this first weekend.

I will check the batteries in a couple of days when I get it out of storage. There is a receipt for the batteries if I remember correctly.

I like the idea of the portable battery station as a backup. Any recommendations on that? Seems like I can have that and charge it via solar panels in the future.

Yup,
I can’t make a solid recommendation because I just (2 weeks ago) bought a cheap Chinese 299wh gizmo (PROGENY 300) on Amazon for $200 (with coupon). Ridiculous low price compared to others I had looked at that had all the features I wanted. My imperatives were: LiFePo4 battery, mppt solar charger, regulated 12v output, and standard connections. There are some things I don’t like about it, like a pretty useless SOC display, but so far I’ve been impressed with it. I paid so little, I’m expecting it to go belly up on me at some point. In testing, I’ve been able to run cpap for 3 nights with the humidifier on (that’s huge). It charged from 0 to 100% in 6 hours on household 110v. Haven’t tested the solar charging speed yet, but the controller does work, as does the 12v car adapter charge circuit. I’d recommend a better brand name if you want to keep it a while. But, hey, I’m cheap and got my head turned by this one.

Marine359 · 09-29-2021, 12:35 PM

Mashmaster,
Please be advised that DavidM is correct about 99% of the time.
For the other 1% count on me.

BobC · 09-30-2021, 08:59 AM

TV power consumption varies by type, LCDs use more than LEDs. A 40" LCD will use 100w while a 40" LED, uses only 50w:

https://www.batteryequivalents.com/o...-a-tv-use.html

The 300W Prodigy power station will theoretically power a 40" LCD TV for about three hours, but that's probably optimistic, given the tendency for manufacturers to oversell. If your TV is an LED TV, you can double that.

I don't know about the Progeny 300 power station (aka solar generator) but the market is flooded with both high and low quality options. Will Prowse, a popular and well-regarded Youtuber is constantly reviewing them. Here's a link to the "solar generator" playlist on his Youtube channel:

https://www.youtube.com/playlist?lis...3i93Qxb3DumV-y

And here are his current recommendations:

https://www.mobile-solarpower.com/ul...e-systems.html

The best suggestion I can give regarding boondocking is "think camping, not Rving". This means, turn off your lights when not using them. Use your propane stove to heat things and to make coffee, read books and enjoy nature instead of watching TV, etc. It's still going to be a lot more comfortable than tent camping. Here's a great, non-electric espresso/coffee maker:

https://aeropress.com/product/aeropress-coffee-maker/

I purchased an inexpensive battery monitor like the one DavidM suggested for my van to keep track of my power. The Victron monitor is the current gold standard but they're over $200:

https://www.amazon.com/Victron-Energ...3011812&sr=8-4

Victron also makes the $139 SmartShunt that uses your cellphone as the display. I'll probably get this for my MH:

https://www.amazon.com/Victron-Smart.../dp/B0856PHNLX

Mashmaster · 09-30-2021, 09:21 AM

I ended up purchasing a Jackery 500 power station and solar panel based on a conversation and recommendation with a friend who is big into Class B boondocking. They actually are having a sale through today and every review is that this is a solid unit that should last and work consistently even though it is slightly more expensive than the others.

Understood about being totally off grid, but I do need to be able to work while boondocking so I needed something to help that.

I will look into adding a battery monitor anyway because that looks like something really useful.

BobC · 09-30-2021, 09:53 AM

Quote:

Originally Posted by Mashmaster

I ended up purchasing a Jackery 500 power station and solar panel based on a conversation and recommendation with a friend who is big into Class B boondocking. They actually are having a sale through today and every review is that this is a solid unit that should last and work consistently even though it is slightly more expensive than the others.

Understood about being totally off grid, but I do need to be able to work while boondocking so I needed something to help that.

I will look into adding a battery monitor anyway because that looks like something really useful.

I think you made a good choice.

You'll know a lot more about your requirements after your first boondocking experience. What solar panel did you get?

Mashmaster · 09-30-2021, 10:11 AM

Quote:

Originally Posted by BobC

I think you made a good choice.

You'll know a lot more about your requirements after your first boondocking experience. What solar panel did you get?

I got the Jackery 60Watt panel. We get so much sun here in Texas that it should work well to charge it. My friends said that they are never charging it from zero, it is always topping it off. This unit was 50% of the cost of the 100Watt panel from them.

I figured the matching set will connect better and not invalidate any warranty

BobC · 09-30-2021, 12:41 PM

Quote:

Originally Posted by Mashmaster

I got the Jackery 60Watt panel. We get so much sun here in Texas that it should work well to charge it. My friends said that they are never charging it from zero, it is always topping it off. This unit was 50% of the cost of the 100Watt panel from them.

I figured the matching set will connect better and not invalidate any warranty

I wish you'd sprung for the 100W panel even though it's more expensive. Any chance you can exchange your's?

You can also use your panel to keep your batteries house topped off once your Jackery is charged. Your panel won't be able to keep up with a typical load but will help. Even though it's only 60W, it will be more effective than a rooftop panel of a similar size since you can optimize it's orientation. We camped for several years with only 100W on our first TT and for several years after that with 200W on our second. We came from a sailboating background and were used to conserving power.You'll need a simple controller and will need toad an inexpensive controller and some Anderson Power Pole connectors to mate with your panel. I'd recommend using 10 gauge 12V landscape wire twin lead for your cord (12 gauge will also work but 10 is better. It's available at Home Depot. The following sounds complicated but it looks that way due to having to use a variety of adapters to make it work.

Basically it's:

Panel > extension cord > controller > battery

Here's one example Solar Controller:

https://smile.amazon.com/ZEALLIFE-Co...7F85CDM6&psc=1

Anderson Power Pole adapter (to connect the panel to the extension cord):

https://smile.amazon.com/Apoi-Adapte...3025948&sr=8-9

The above controller uses SAE connectors so you can use these to make up your extension cord:

https://smile.amazon.com/gp/slredire...getName=sp_mtf

From there you can decide how you want to connect to your batteries, SAE connectors, alligator clips or hardwired SAE port:

https://smile.amazon.com/CERRXIAN-We...026361&sr=8-13

In any case, you want your controller as close to the battery as possible:

Panel > Power Pole adapter > SAE plug >extension cord > SAE plug > controller > house batteries

or:

Panel > Power Pole adapter > SAE plug >extension cord > SAE plug > SAE port > controller > house batteries

Note that the SAE plugs are polarized so you need make sure the orientation is
correct. The exposed male plug is always negative.

Mashmaster · 09-30-2021, 12:46 PM

Quote:

Originally Posted by BobC

I wish you'd sprung for the 100W panel even though it's more expensive. Any chance you can exchange your's?

.

Technically I could. But for the price, I could get two 60 Watt panels. Would it be better to daisy chain them?

BobC · 09-30-2021, 01:06 PM

My quick answer is yes. They even show this on their website and may be able to supply the necessary connector. You'll also have to ask them if the 500 can handle two 60W panels. The link below shows a larger unit:

https://www.jackery.com/pages/solar-generator

What I don't know is their connector parallel (+ to +, - to -) or is it series (+ to -, - to +)

This is important if you want the ability to charge your house batteries. The output voltage of the 60W panel is 22V so if it's parallel, the output for two stays at 22V and the amp output doubles. If it's series, the voltage doubles and the amp output stays the same. This will make a difference as to what controller specs you need.

If the connector is parallel (most likely), the controller I linked is OK. If the connector is series, you'd need a controller that can handle 44V.

DavidM · 09-30-2021, 01:08 PM

Presumably the Jackery has a built in solar controller that takes input directly from the solar panel and converts it's voltage to what the Jackery's batteries need for charging. In that case you can't wire two panels in series, only in parallel since I suspect the Jackery's controller is PWM not MPPT which is what it would take to use two panels in series.

David

Mashmaster · 09-30-2021, 01:28 PM

I sent a message to Jackery

Marine359 · 09-30-2021, 02:11 PM

22v is not the voltage the controller sees, it’s VoC (open circuit voltage). The controller actually sees 18v from most panels. Also need to be aware that some controllers will not work well unless the delta between input voltage and battery voltage is less than 5v. If you have LA batteries, it’s never really an issue because average 100% SOC for LA is about 12.7v. But if you have LiFePo4, which typically has a 100%SOC of 13.6 - 13.7v, the controller may not fire up if your battery is near full charge, and you’re looking to “top it off”. I’ve experienced this with my Victron mppt controller. After plugging in the panel, the controller and my shunt did not show positive charge amperage. After discharging the battery a while, the controller fired up all by itself. Had to read my Victron manual to figure that one out.