Want to install solar in 2018 T@B 400, need advice

Deb55

We have a 2018 T@B 400 without solar. We're thinking of having solar installed, and I'll be discussing it with the service guy at the dealership soon. I wanted to run my thoughts by this group so I can get your opinions, suggestions, etc.

I'm considering rooftop panels, 200 watts total.  I'm also thinking of adding a second battery just like the one we currently have (the large AGM battery). My thinking is that with the 200 watts and two batteries, we'll be able to boondock for a pretty good amount of time. What do you think? Is this a good idea, or is it overkill? We won't be installing lithium batteries--they're just too expensive.

Comments? Keep it simple - - I really don't know anything about solar or batteries, but I want to at least have enough knowledge to discuss options at the dealership's service department.

Thanks!

Sharon_is_SAM

Here is a nice little etrailer tutorial on solar and batteries.  https://www.etrailer.com/faq-how-much-solar-power-rv.aspx

It sounds like you want to double your battery capacity, but I would not recommend the large 12 volt battery (history of premature failure and nuCamp is no longer installing them).  I would add two 6 volts and switch between the 12 volt and the two 6 volts, then, when the 12 volt dies, go to an all 6 volt system.  Not sure how you would arrange the solar charge controller for this set up.  

Keep in mind, if you have rooftop panels you must always park in the sun.  Portable panels give you options.  Combining the two is the best of both worlds.  With the right conditions for solar,  I would guess many Tab owners are able to boondock with 200 watts and the large batteries almost indefinitely with any battery system with 200+ amp capacity, so you may not need any extra battery at all.

Do you have an idea of your daily amp usage?  That is where you need to start.  

Deb55

@Sharon_is_SAM, thanks for the tutorial! I've just skimmed it so far, but plan to spend more time with it later.

We're not big power users, at least I don't think so. We don't have any microwave, hairdryers, or any power kitchen appliances at all. We use the lights, the TV for maybe the length of a movie, the water pump, the refrigerator, and the fans. Last summer we moochdocked in a friend's driveway at the beach for about a day and a half in full sun. It was hot, so we had the fan on high all night. It probably drained 50% of the battery. We bought a Maxxair fan and will be replacing the fantastic fan with it, which should use less power.

So, maybe 200 watts of solar and the large 12v AGM battery that we already have (225 amps, right? ). Then we can use that for awhile and reassess. We're hoping to do some Harvest Host stays, or campgrounds that don't have hookups in the future. We're very new at this, and have only stayed where there are full hookups, other than a couple of Cracker Barrel stops and the one beach overnight. 

Cherokee

I have two golf cart 6V batteries wired in series and the storage capacity is a great improvement!  I also like our portable Zurn  solar system : https://www.zampsolar.com/portable-kits  - park the trailer in shade and locate the panels where the sun shines! 

Deb55

@Cherokee do you have a T@B 400? I thought you couldn't use the golf cart batteries in the unvented space under the bed. Plus, I really want a roof mounted system, and maybe add an additional suitcase panel later. I just don't want extra equipment to carry and set up if I don't have to. 

pthomas745

It would be best to get a handle on your power use, as @Sharon_is_SAM pointed out.  And, how many amp hours exactly does your 225 amp hour battery provide?  For maximum number of cycles from your battery, many battery people recommend only using 50 percent of your available amp hours.  So you have roughly 112 amp hours to use.   Everything you mentioned in your post about usage has been measured by Tab owners in the past, and you can get a really good idea of how many amps you have used just by thinking it through. 

2 hours of a movie?  Maybe 3-6 amp hours. 

The fan, on low, uses maybe 2 amp hours.  You can run it a looonng time before you would use 50 amp hours (about half your available battery amp hours).

The little LED lamps in the trailer hardly use anything.

The pump will use about 2 amps an hour, but only when it is actually pumping water.  You would run out of water way before it would make a big dent in 112 amp hours.

You have more amps available than you might think.  The trailer is pretty efficient on power.

The thing I don't know about the 400 is the fridge.......someone will have to fill in for me the power usage there.  That will be your biggest energy user, and probably the best reason to expand your battery capacity.

Jenn G's website on battery management is still a great read.

https://jenngrover.com/2015/11/guilty-as-charged-rv-battery-use-management/

There is also a Tab 400 manual in the user manual section that has a spreadsheet on the usage of the various items in the 400 which will also help with your calculations.

pthomas745

I made a screen shot of the 400 usage power spreadsheet.  Use this as a guide, as your trailer's equipment may not match exactly.

Cherokee

Deb55 said:

@Cherokee do you have a T@B 400? I thought you couldn't use the golf cart batteries in the unvented space under the bed. Plus, I really want a roof mounted system, and maybe add an additional suitcase panel later. I just don't want extra equipment to carry and set up if I don't have to. 

I have a 320, but this video may help:

https://www.youtube.com/watch?v=By0mtx7JC2I

Denny16

@Deb55, you can install the same solar panels that nuCamp used on its current TaB400s, which is a nice 194 watt one piece panel that is adhered to the roof, and covers the worse leading down through the back closet.  A Victron BlueTab controller is mounted under the bed, and connects to the battery setup.  Total cost for this setup is around $1200-1400, and can be installed by most dealers with a service department.  Some have done the install DYI.  This is the best setup,I have seen, and we this setup on our 2018 TaB400.
cheers

Deb55

@Cherokee I'm a big TWD fan! I'd love to go with the lithium option that he's talking about, but we've hardly used our 400 yet, and don't think the current 12v AGM is ready for replacement. I think I'll just concentrate on installing solar, and see what our battery options are when we need to replace. Maybe by then the lithium batteries will be cheaper! 

Deb55

@Denny16 I think this sounds like the best approach for us at this time. I'll talk to our dealer about this when we go to have the maxxair fan installed. Good to go armed with a bit of knowledge! 

rfuss928

Maybe the simplest answer I can provide is a brief summary of our experience.
During the first full season of T@Bing we thought we would be all set for weekend camping by doubling our battery capacity.  We added a second AGM battery matching the existing year old battery to that end.  Refrigeration turns out to be the largest power user and the 150AH available was often marginal for our "weekends".  We began looking for solar options and ultimately added 136 watts of roof mounted panels and a quality PWM controller.
We have virtually ignored the batteries ever since.  The panels keep the batteries topped off constantly and we are confident in most situations we will have enough capacity and gains to camp indefinitely.  Because a few times we were a bit stressed about power after several overcast days off grid, we now carry a very compact 80 watt panel for supplement in similar situations.  Generally we stay in developed camp grounds and opt for W&E sites when available (to run the AC), but overnight frequently on long road trips and take any available site when availability is scarce.
Last year we began having battery issues and needed to replace our 7 & 8 year old batteries.  This was the first maintenance needed since installation.  I do have a battery voltage monitor and watch it like you might a fuel gauge while traveling.  I don't obsess because I've learned what to expect.  Like my car, I start paying closer attention when we're in the lower half of capacity and looking for fuel sources when in the last quarter.
Overall, solar is possibly our best modification / upgrade ever.  If for no other reason, the peace of mind provided that the batteries are not a concern. 
IMO - Your plan to add 200w on the roof and double your battery capacity is a very good starting point and may be all you will ever need.  The experience it provides will tell you what, if anything, would be needed in the future.
Have fun!

Denny16

Good points, however, the TaB300 series has a smaller battery, usually a group 24 100 amp.  Your refrig sounds like it is the older 3-way, less efficient, especially under 12vdc, than the new AC/DC.

The 2018 TaB400 has a 224 amp hour battery, so the 194 watt solar works well to keep this charged.  The TaB400 refrig is the newer 2-way, and gets better run times on 12VDC, using less amps.
cheers

Cherokee

Boondocking with solar in Death Valley Two 6v golf batteries are all we need if we re out for 4 or 5 days with solar to recharge them. Note - we do have a 3-way fridge that's most effect on propane. What we saved on not buying Lithium batteries more then payed for the premium solar system. 

Sharon_is_SAM

@Denny16, the clamshells do not have 3 way frigs.  The frig is a 12 v and is more efficient on 12 v than the 3 way on 12 v.  As I recall @rfuss928 upgraded his power to two Optima 6 volt AGMs and installed them inside the TaB.  I believe he has over 200 amp capacity.  

Denny16

Thanks, then he should be good to go, and be able to run that fridge for a week.  Solar will help to extend that range considerably, and he should get at least a 150-200 watt solar panel setup.
 I was not sure at what point the 2-way DC fridge was used in this camper, guess they went from an ice chest to the DC fridge.  
cheers

Sharon_is_SAM

The Tab clamshell is not like a TaG.  I don’t think they ever had an ice chest - always a frig.  I know of at least one owner who had a Norcold chest style frig installed.  Same that was used in the TaG up until the latest Yeti cooler placement.

Denny16

OK, getting my models mixed up from photos I have looked at. Thanks for the update.
cheers

rfuss928

Sharon_is_SAM
One of my points was that I had a year old 12v AGM and added a second matching 12V AGM with no issues.  I replaced the Optimas pictured with a pair of 12v DuraCells  with 100AH ratings each.  I like having the option of running on either or both batteries.  It came in handy managing failing batteries discovered while traveling last year.

My refrig is the original 12v only Norcold that is a reasonably efficient unit.  ~3A running  ~50% duty cycle depending...  I expect it may use less energy than the much larger unit in the 400. 
In the spirit of "keep it simple" from the OP, the system proposed by Deb55 is a straight forward upgrade that IMO, likely will work well in many situations and provide a good base to learn from and build upon if required.

Cherokee

Deb55 said:

@Cherokee I'm a big TWD fan! I'd love to go with the lithium option that he's talking about, but we've hardly used our 400 yet, and don't think the current 12v AGM is ready for replacement. I think I'll just concentrate on installing solar, and see what our battery options are when we need to replace. Maybe by then the lithium batteries will be cheaper! 

A lot of people get by with 2 6v golf cart batteries - what you save by not buying lithium, you can get a premium solar charging system and have a lot of money left over. You might try this first and see if it meets your needs - you can always drop a thousand dollars on lithium batteries later if you go for days boondocking in overcast weather.

Sharon_is_SAM

@rfuss928 - I was close!  You went with two 12 volts - not two 6 volts.  I understand your offered point to Deb.