Tab 320 - Battle Born Package - A/C

EasternJL

Hi folks-- We're considering the purchase of a 320 (and hoping to try one soon).  We've never owned a camper before.  The Battle Born package is a pretty significant upcharge, but with the difficulty in finding electric sites (especially on weekends), it seems like it might be worth if for the flexibility of camping at non-electric sites.  One question is about what this add-on buys us, in terms of capacity over time.  Can we run the A/C overnight (and some in the day) at a site in the summer where it's 85 or 90 during the day and 65 at night?  And how long will it last?  And I'm assuming that the solar won't be adequate for full recharging during the day? I do realize that it's impossible to give a firm answer, but I'm hoping some folks with experience can give us some real world feedback.  Basically, would be able to get away with 2 or 3 nights at a tent site in a summer setting?  Thanks!! 

pthomas745

Welcome to the Forums!

Sounds like you have a decent handle on the pros and cons of "running the AC on battery."  Running the AC on battery has gone from barely possible, to expensive and kinda possible, to less expensive and possible with some caveats and disclaimers.  All in the last 4 years.  Some owners here have some good comments on the subject.

The new lithium battery setups in the Tabs are still pretty new to us.  It will be interesting this summer to find out how owner's expectations meet lithium reality. 

Look over this thread. There are another couple of threads linked in it that go back a couple of years to owners who set up their own "big battery" and "big panel" setup and ran their air conditioner "with caveats."  For the 320, the solar setup may have to be supplemented with a portable panel, at the very least. Recharging will be the biggest issue.

https://tab-rv.vanillacommunity.com/discussion/15726/running-air-conditioner-off-lithium-batteries

EasternJL

Thanks for this feedback!  I'll take look at that thread.

I suppose on the recharge, our small portable generator (quiet) could be used to supplement the solar, but I'm sure it's not kosher in tent areas to run generators for long.  I figure it would be later this summer before folks with the BB package would be able to provide feedback on run times, etc.

CharlieRN

I don't know if the new 320's use the same Air8 air conditioning unit as my 2021, but think they do and in any event, the specs are likely to be similar. Here's the specs for the Air8:

• Nominal cooling capacity 8000 BTU
• Power consumption 1000W
• Starting current 15 A (<1sec)
• Operating current 9A
• Air flow 220 CFM

I'm far from an expert on things electrical, so take the rest of this post as a best guess and not gospel. There are plenty of folks with substantial electrical expertise on the forum, and hopefully, they'll comment and more importantly, point out any errors on my part. With that out of the way, here goes

The Battleborn package gives you 200 amp hours of capacity and a 2,000 watt inverter. As you can see, the starting load on for the Air8 is 15 amps, which would be something like 1,600 watts. So the inverter should be able to handle the starting load. The Air8 at normal operation is 9 amps/1,000 watts, again within the nominal capacity of the inverter. If the starting load is a concern, you can mitigate that soft with a start device that will smooth out the load at start-up. One manufacturer claims their device "can deliver 65% to 75% start current decrease, as compared to a compressor’s locked-rotor amperage (LRA)." I have no experience with the device, so don't know how accurate the claim is.

I think the bigger problem is likely to be the capacity of the batteries. The BattleBorns can provide 200 amp hours, which is quite a bit. That's from fully charged, down to zero however. So effectively, you have something less than than that. To make the math whole numbers, let's say you have 180 Ah. The Air8 uses 9 amps, which means 20 hours of operation (180 Ah/9A). There are other devices on the T@B that also require power however and the inverter is not 100% efficient. The refrigerator is pretty efficient, and it doesn't run constantly, but it still uses a fair amount of current. There are also devices like the CO detector that use small amounts of current, but are always on, so are a constant drain. What this means is that the Air8 doesn't have the batteries all to itself.

Of course, your solar panels will recharge the batteries to some extent. I don't know if the new 320's have more solar capacity, but the panels on my 2021 provide something like 100 w at peak. That helps, but I don't think it will be sufficient to bring your bank back to full, particularly if you use the A/C a lot. You can always add additional panels however, and that will extend you ability to recharge.

You'd need to add up everything that needs power to see how long you'd be able to run the A/C. It's likely to be a considerable number of hours, but probably not all day, and almost certainly not two or three days unless you added more solar panels or batteries (or both.) As I said earlier however, I'm not even close to being an expert in this area, so hopefully those with more knowledge will chime in.

Edit: typo, spelling.

VictoriaP

From this article (https://www.solarempower.com/blog/how-long-will-200ah-battery-last/):

A 200Ah lithium phosphate (LiFeP04) battery connected to a 400 watt DC load with 80% Depth of Discharge will last for almost 5 hours.

So let’s see, you have a fridge which we know already consumes about 30 Ah per day of use. And an A/C that consumes more than twice the power of the 400 watt load listed in the above reference. Plus some loss of efficiency due to the inverter, because A/C on the 320 is powered off the 110v system, not the 12v, so the inverter is required. At best, with the fridge off, it appears you’re still only looking at a few hours to deplete 200 Ah of batteries. Which your 100 watt panel will not restore in one day, since it takes more than a full day of maximum sun (an impossible thing in itself) to recharge 200 Ah from a single panel.

This setup really appears to be designed more to run the A/C briefly while you’ve stopped at a scenic overlook for a quick lunch in the trailer during the drive to your destination, and for cooling off for an hour or so in the evening. It’s not nearly capable enough to power A/C nightly while boondocking on a multi-day stay. And generators are often limited to certain hours or banned outright. If A/C is truly a requirement, you’re still best off getting a powered site.

That said: I personally wouldn’t consider boondocking with a 2021 or later 320s with less than the 200 Ah of this setup. Again, you have a fridge that eats 30 Ah per day, combined with the fan, entertainment system, water pump, lights, etc., and a bunch of parasitic loads because some of these things don’t turn actually turn completely off unless you add kill switches to them. I also personally wouldn’t boondock without an additional portable solar setup of 200 watts to pair with that battery configuration, because at the very best ideal conditions, a 100 watt rooftop panel still doesn’t actually give you 100 watts. Under less ideal conditions? I’ve seen as little as 6 watts on an overcast fall day in the northwest…latitude & season both matter, as much as clouds and trees. Solar’s truly an amazing thing, but a 100 watt panel on a curved roof just isn’t enough in many locales, not with that fridge chewing through your battery. And rooftop + portable solar is ideal…you can get some charge while driving and at some times of day from the roof, and can park in the shade while still capturing some rays by putting the portable into the sun.

So regardless of A/C use, I’d spring for the package unless you are comfortable with DIY electrical. It’s expensive, but it’s using also top of the line components.

(All this goes out the window for older models. 3 way fridges on propane cut your power use WAY down. I can run my entire Tab minus A/C on 9 Ah a day, which is easily restored in a couple hours by a 200 watt portable panel and decent sunlight.)

EasternJL

Gosh, y'all-- thanks for super thorough feedback!  Victoria, I think you are right- it's probably worth it even if it's not covering everything we want to do.  I can hear myself grumbling in the future if I go cheap and don't get the package---"I should have just gotten the BB package", etc.  With this said, it would be interesting to hear from some folks as the summer goes on about their real world experiences.  

Da_Birds

I'd suggest getting the BB package regardless. If you intend to do any boondocking you will more than likely wish you had those additional AH's.