Solar and Walmart Campground

[Docbutch]

Our Tommy Bahama has solar panels. We plan on using solar only for "Walmart Campground". What can we run, or conversely, what can't we run during our Walmart stay. Secondly, what does Walmart, in general, think about using their parking lot as a wayside?

[Acheron2010]

Check with RV camp applications like RVParky or Campendium - not all WalMarts allow overnight parking.
You can run your refrigerator, hot water heater, and heater on propane.
For electricity, you can run the Fantastic Fan and stove vent and stereo.
When you turn on your inverter, you can run about any appliance you can plug into a 120V outlet. Heat-type appliances, like blow-dryers or toasters or elec. coffee pots will suck down your batteries.
The best way to do this is go to a regular campground for a couple of nights with full hookups. Spend one day fully hooked doing all your regular routine. The next day, unplug, and do it again. You will quickly learn whether you can survive overnight, and what if anything in your routine has to change.

[SeaLevel]

Your inverter is probably 1000W, which won't be enough to run some appliances, and not all of your outlets are energized by the inverter.

[AirMiles]

Originally Posted by Docbutch

Our Tommy Bahama has solar panels. We plan on using solar only for "Walmart Campground". What can we run, or conversely, what can't we run during our Walmart stay. Secondly, what does Walmart, in general, think about using their parking lot as a wayside?

Do you have two 80W panels? That 160W of panels can produce 480W on a typical sunny day. 480w/13.5a=35AH of battery charging. What can I run on 35AH per day? I can run my refrigerator on propane which takes 24AH and have 11Ah for other items. You will need some amps for the propane water heater, water pump and lights. You will still have a few more amps which could run the fantastic fan for a few hours or maybe one hour of TV. That is what I think your solar can maintain on a daily basis.

Now your batteries will have some amp hours in storage. So you could run the fantastic fans all night or more TV if you will be connected to shore power within a day or two.

The above also assumes the factory solar is as efficient as my self-installed solar installation with a Victron controller and 6 Gauge cable to the bus bars. If I had factory solar, I would consider upgrading the controller to a Victron and upgrading the controller to busbar cables to 6 gauge to increase its efficiency.

[Adventure.AS]

Solar PV is redundant when travelling as your TV will likely fully charge your house batteries while towing. As you will be stopping at Walmart late in the day and leaving early in the morning, when the sun is low, your solar panels will not be of much help. They can help charge your batteries on sunny days when you are boon docked for several days.

[Mollysdad]

Originally Posted by docbutch

what can't we run during our walmart stay.

a/c

(That's funny, I typed A/C and the post is a/c)

[lsbrodsky]

Adventure.AS has it nailed. By the time you pull into a Walmart and stay overnight your batteries are charged. You should be more concerned about the health of your batteries, their capacity. With healthy batteries you will easily have enough capacity to run your refrig and hot water on propane(they require DC control power), water pump for showers, LED lights, and a Fantastic Fan. You are pushing it if you plan to use your inverter for anything including TV, toaster, coffee pot, etc.
You will not stay more than one night as they generally do no allow it. We prefer Cracker Barrel, seems safer and quieter.
Larry

[SewStream]

@Docbutch - if I am correct, your 27’ is nearly the same layout as our 27’ Globetrotter. Here is our experience boondocking/dry camping in a parking lot overnight. We had the same factory solar set up with the 1000W inverter. We did not use a generator. Batteries were fully charged when we arrived.

First total fail - the outlet in the galley is NOT an inverter outlet! If you have plans to use electricity in the galley; forget about it. No coffee maker, no Instant Pot, no nothing. Fortunately, we can make pour over coffee using the range and a tea kettle.

Second total fail - the outlet in the lavatory is NOT an inverter outlet. And, my hair dryer is 1200W. No can do. If you use an electric shaver; forget about it.

Third total fail - after running the Fantastic fan overnight, our batteries were at 36%! They should not go below 50%. Therefore, you cannot safely run the fan overnight without damaging the batteries.

Our conclusions about the factory solar package - it is only good for keeping the AGM batteries charged when your AS is in outside storage, and using the lights in the coach. Everything else (at least for us) will damage the batteries because they draw too much from the battery storage.

Our solution was to remove the factory solar package and upgrade our solar capabilities to support our boondocking Airstream lifestyle. Now we can use all our appliances, and even run our air conditioning for a few hours off of our solar/lithium batteries.

[AirMiles]

^^^^^Agreed!!!!!

My self-installed 400W of solar with a Victron 100/30 controller, using the factory prewire, can easily replace the 100AH per day I use from my 230AH golf cart batteries. Its like having "perpetual" battery power for boondocking. But some things cannot be powered from the small 1000W inverter and a small 230AH battery bank, such as the microwave and A/C, so I carry a generator to power those appliances.

My experience with the factory non-solar charging system, including the converter, Interstate batteries, and 12V charging from my tow vehicle was also a "total fail" for boondocking.

[OTRA15]

Originally Posted by Docbutch

. . .
. . . what does Walmart, in general, think about using their parking lot as a wayside?

There is a Sticky thread on this general topic FYI, with over one-thousand posts:

http://www.airforums.com/forums/f42/...ing-13082.html
Sticky on top of the list here: http://www.airforums.com/forums/f42/

As you can see, the reception at each Walmart varies widely.

FYI

[SMKovalchik]

Have to get this off my chest. Why do people pay large sums of money to purchase an AS and tow vehicle then go cheap and sit in a parking lot? Understand if you’re “stuck” but a little planning would avoid that. Campgrounds are important and why not support them!?! Many are family owned. WalMart sure isn’t camping.

[lsbrodsky]

Here is one answer. I have been on trips where there was absolutely no campground within a reasonable distance of the point where I needed to stay overnight. When I plan ahead, I try to use courtesy parking for that, but the coverage is limited. However, there always seems to be a Cracker Barrel or Walmart when necessary.
Larry

[rmkrum]

Not everyone has the cash flow needed to pay for campgrounds all the time. Retired folk may be subject to this as well.

Besides, we don’t need many amenities when we stop overnight on a trip to get somewhere. A dump station, and 30-amp power in the summer is all we typically need. Our inverter generator is quiet enough if no power is available.

If I am making tracks cross country to a destination, it’s often easier to moochdock in a Walmart or Cracker Barrel lot than try to do the detailed planning to reserve spots in a campground.

This also avoids the “gotta get there syndrome” that makes you try to drive too late at night or too tired to make a reservation. If your Airstream is set up for even light boondocking it may be easier to just stop and camp out and get a nap instead of risking an accident.

We also travel with dogs, and potty breaks for them and us are highly variable in duration and spacing. Better to build on a lot of slack time, or just eliminate the urgency of making it to the next pre-paid stop.

[uncle_bob]

Hi

If you have the "stock" battery setup you likely have two 100 AH AGM batteries. That gives you 200 AH total of which half is "usable capacity". Roughly speaking 80 to 100 AH per day is not an unreasonable "power budget". You can get below that with some care. Inverter use is likely to make getting below 60 AH pretty hard.

If your "charge wire" from the TV is typical of many, you will get around 6A of charge current from it. Drive for 4 or 5 hours and you put 20 to 30 AH into the batteries. On a lot of vehicles, getting *anything* from the charge wire is a challenge ( relays / fuses missing ....).

Solar varies all over the place depending on things like shade and clouds. On a *really* good day the factory two panel setup might get you 50 AH. On a more normal day (at least around here ...) you could see half of that or less.

A lot of this gets clouded by the way a lead acid battery does its thing. Getting to 80% charge can be pretty quick. The next 20% may take quite a while. Since you are always operating above 50%, this *is* the region you will normally be in.

One thing that is *very* worthwhile is a shunt based battery monitor. Without one it is *very* hard to figure out what's what on a battery system,.

Bob

[SewStream]

Originally Posted by jschloo

Our CarGenerator provides power at night or in the rain , up to 1000 watts. Then we go to bed happy and with a fully charged trailer battery.

Does this mean you must run your truck on idle all night to use the CarGenerator? What about the exhaust fumes from your TV? I’d love to hear more about your setup. We could not get enough power from the factory AGM batteries to even run the Fantastic Fan overnight without a (almost) complete drain.

[uncle_bob]

Originally Posted by SewStream

Does this mean you must run your truck on idle all night to use the CarGenerator? What about the exhaust fumes from your TV? I’d love to hear more about your setup. We could not get enough power from the factory AGM batteries to even run the Fantastic Fan overnight without a (almost) complete drain.

Hi

The Fantastic Fan on high pulls just under 3A. On lower settings, it pulls less current. Fan + fridge should come in right around 4A. Over a 12 hour "night" that
would be 48AH. If the AGM's are fully charged, that's half their 100 AH usable capacity.

Again, without a shunt based monitor (like the BMV-712) you really don't know if your batteries are fully charged or not. It can take most of a day (= 24 hours) on shore power charge to bring them up to "full". That's one of the gotcha's with a lead acid battery.

Indeed, if it's very hot or very cold out, your charger isn't going to quite do what it should. The answer there is a temperature compensated charger. The same temperature stuff will fake you out big time trying to guess charge state from a voltage reading.

Bob

[Lily&Me]

And seriously, if you must run a generator or vehicle all night to power what you must have, strongly consider a traditional campground with electricity.

WalMart is WalMart, it is not a campground.

Imagine a number of vehicles doing this, others nearby subject to the noise and fumes, and eventually this option would become prohibited in many more places.

Maggie

[stevejones]

Originally Posted by uncle_bob

If you have the "stock" battery setup you likely have two 100 AH AGM batteries. Bob

Our 2019 Globetrotter only had two 80AH AGM batteries (not 100AH). At 50% max discharge for AGM that is only 80AH usable. The OP probably has the same batteries.

I was initially a fan of the factory solar install but now feel it is more of a marketing thing. It will help charge your batteries but I don't think it has enough capacity to fully charge them if you've discharged them down to 50%. I guess if you keep your power usage low and your trailer is in direct sunlight, it can maintain your batteries enough to provide the basics for the 12V systems. But I wouldn't use the inverter much. Don't run your furnace or fantastic fan all night. And constantly check your battery voltage.

Steve

[AirMiles]

Originally Posted by stevejones

Our 2019 Globetrotter only had two 80AH AGM batteries (not 100AH). At 50% max discharge for AGM that is only 80AH usable. The OP probably has the same batteries.

I was initially a fan of the factory solar install but now feel it is more of a marketing thing. It will help charge your batteries but I don't think it has enough capacity to fully charge them if you've discharged them down to 50%. I guess if you keep your power usage low and your trailer is in direct sunlight, it can maintain your batteries enough to provide the basics for the 12V systems. But I wouldn't use the inverter much. Don't run your furnace or fantastic fan all night. And constantly check your battery voltage.

Steve

The problem here is having two low-amp-hour batteries not getting fully charged by 160W of solar. If your batteries aren't getting fully charged, you would not be able to use the furnace or fantastic fans all night.

I have four 100W panels running on the factory prewire with a pair of 6V golf cart batteries and a Victron 100/30 controller. My system allows me to run the furnace or fantastic fans all night, watch some TV, and power all the other needs including refrigerator on propane, water pump, water heater on propane and light. A generator is needed for microwave and A/C use. With 400W of solar, my 230AH battery bank gets fully charged each day.

I think the Airstream factory solar can be improved by installing a Victron 100/30 solar controller and increasing the wire between the controller and busbars to 6 gauge. Doing just these two improvements may get your battery fully charged.

The next step would be to add two more matching solar panels and wire all the panels in series-parallel. This will increase the system to 320W which would be enough to fully charge a pair of wet-cell batteries.

Then the only remaining question is whether the factory batteries have been damaged from being consistently in an undercharged state or from being drawn down too deeply in the past. If the batteries are damaged or weak, a new pair of batteries would also be needed to be able to use the furnace or fantastic fans all night.

[OTRA15]

Originally Posted by SMKovalchik

Have to get this off my chest. Why do people pay large sums of money to purchase an AS and tow vehicle then go cheap and sit in a parking lot? Understand if you’re “stuck” but a little planning would avoid that. Campgrounds are important and why not support them!?! Many are family owned. WalMart sure isn’t camping.

What . . . ?

Too many judgments above to warrant any further energy IMO.

Great recent comments.

Doh . . .