Modifications to our 2017 30’ Serenity (Interior upgrades + Solar/Lithium)

[TouringDan]

Great design work and attention to detail. Thanks for sharing. If I ever had the means and the desire for a new Airstream I would probably copy some of your modifications. Of course I may copy some of them anyway when I restore our 34’ that presently is on the back burner.

Dan

[uncle_bob]

Originally Posted by wulfraat

I disconnected the 12v supply from the TV. Charging from the TV is a rounding error - opted out of that.

Hi

Ok, so in the planning thread I recommend pulling the wire and I wound up with a DC/DC. In the same thread, you proposed the DC/DC and I wound up putting one in.

In my case (with two solar panels) the charge current from the TV, the contribution of an 18A DC/DC when towing *will* make a difference. At least that's my guess.

Bob

[wulfraat]

Bob - you are correct. For most systems I would definitely recommend a DC-DC converter to delivery supplemental charging from the TV and it does make a difference.

In my system, I have so much battery capacity and so much solar, however, it didn't really matter (my TV will push out 30 amps of charging if I need it). My panels will deliver over 4kwh / over 200ah back into the batteries on their own in a given day.

Also - my other consideration was that I manage my lithium bank to 90% - IE - I don't peg the batteries at 100% and float them. unlike AGMs, Lithiums don't like that for the long run. Much of the time when traveling in the TV I actually disconnect solar and let them sit at 85-90% charge with the basic little house draws and inverter on.

Once or twice a month I'll charge the bank to 100% to balance the cells, but 600ah lets me manage the batteries more conservatively - IE between 50-90% charge most of the time, which is ideal for a long lifespan, from what all my research told me. That's another reason I went with such a large capacity system - I can bounce down to 20% SOC but I likely won't need to often.

[uncle_bob]

Hi

If we are on the road hopping between "informal" sites, the power from the TV ( 18A from the DC/DC) does help compared to our ~ 10A from the solar. How long we drive vs how long we have good sun .... who knows. Neither one will re-charge a dead 400AH bank in a day. I don't plan on running the bank to zero. Nobody should plan like that ....

Bob

[bolerama]

Great thread! Thanks for sharing. Loved your 25SS and love this one too!
Lisa

[Jaxon]

Originally Posted by wulfraat

We can run the main AC while on the road without hookups when desired. This is really our second home and we use a lot of AC ‘gear’ such as hot water kettle, electric grille, ice maker, microwave, AC, TV, computers, etc.. so its nice never to have to worry about drawing down the batteries.. we just go along our way and all is good in 600ah lithium land.

So... AC, microwave, TV, computers, etc. all on solar/battery power? What's the average draw-down time on a given warm day with AC going, computer surfing and music through the stereo?

Very nice setup, Wulfraat!

[Njg]

I’m impressed that you are able to run the AC! So 600ah is the magic number to be able to boondocks with AC? I’m starting this piecemeal and have 400w on top, VictronConnect MPPT AND BMV, planning on multiples Macy year then lithium the year after... was wondering what it would take to run the AC on batts. Nice upgrades!!!!

[wulfraat]

Originally Posted by Jaxon

So... AC, microwave, TV, computers, etc. all on solar/battery power? What's the average draw-down time on a given warm day with AC going, computer surfing and music through the stereo?

Very nice setup, Wulfraat!

Originally Posted by Njg

I’m impressed that you are able to run the AC! So 600ah is the magic number to be able to boondocks with AC? I’m starting this piecemeal and have 400w on top, VictronConnect MPPT AND BMV, planning on multiples Macy year then lithium the year after... was wondering what it would take to run the AC on batts. Nice upgrades!!!!

Not enough data collected yet to share a statically significant sample / projection.. but VRM portal is logging all of my usage online so should be some good analytics to follow.

What I can tell you is that obviously, without the AirCon running the solar array of 8 panels will supply all DC needs without dipping into battery reserve during the day. That is a given. On a sunny day my panels push >40amps DC current at their peak . Cloudy day 50% of that. Overall yield on a sunny day is an awesome 4kwh or in the range of 250 DC amp hours supplied for energy consumption needs. That’s a lot of DC power kicked out by Mother Earth!

Now comes the AirCon - good ‘ol penguin II 15k unit..

AirCon with just a couple other small loads pulls~ 1800watts on a hot day. Like right now - 90 degrees outside - image below as I sit here in the heat (outside) with 13amp of shore power available and a 6pm cloudy sky overheard.

Some theoretical basic math....

Solar yield on a sunny day - 4kwh.
Battery capacity of 600ah with 20% reserve - 5.7kwh
Total power available in a sunny day - batt+solar - 9.7kwh

Penguin II 15k chews up and spits out 1800w - call it 2k watts with some other stuff going like our Ice maker, and no cycling of the compressor (super hot day). Screen shot below as I sit on shore power limited to 13amp output, supplemented by DC power via the hybrid inverter...

So 9.7/2 = 4.85 hours of non-stop running of the AirCon and other items with NO cycling of the compressor. Call it florida or Texas or Haiti heat!

So that is in theory. As I gleam data from the system combined based on my usage patterns and needs I’ll most definitely provide updates as I go along.

When push comes to shove I do have a little propane-converted honda 2000i that I can crank up to supplement (via power assist function in the victron multiPlus) another 1,500 watts constant if I really want to peg the AirCon for 8+ hours straight. I don’t like running the genset because it makes noise. I like peace and quite [emoji4] but I have it if I need it in Death Valley heat.

All that being said you’d need like 20 100watt panels to keep up with an AirCon running constantly and no compressor cycling. I only have 8 panels - so some power management is still needed so you don’t wake up the next morning with no reserve left [emoji4]

[DKGA]

Great idea about the cutting board!
I have already modified ours and the wife loves it.

[slowmover]

I think I forgot to earlier add my congratulations with the Thanks button. Every time I’ve seen your screen name it’s been a reminder to get back here.

Did I miss previous spec or did you have Timeless install antilock disc brakes?

The solar electric is past “impressive”. Is it detailed in another thread?

[wulfraat]

Heya slowmover.... I am still running dexter drum brakes on my 30' unit - works fine for me.

Regarding specs - I put a build description up in post #1 in this thread... here are the various system components that came together for this system:

• 800watts of solar - Eight (8) AM Solar SP100 panels up top. Ability to tilt if needed
• Victron 150/85 MPPT controller (Smart w/BT)
• Victron 12/3000 Multi-Plus inverter/charger with 50A pass-though
  • PowerControl (ability to deal with limited generator or shore power)
  • PowerAssist (ability to dynamically supplement the capacity of shore or generator power with batts)
  • Real-time uninterrupted 120v power supply when disconnecting shore / genset power sources
• Victron Lithium batteries (600ah total - 2 X 300ah batts)
• Victron CCGX monitoring panel with wi-fi and automatic upload to VRM portal
• Victron BMV-712 battery monitor (Smart w/BT)
• Victron Digital Control Center and BMV monitoring panel
• Victron BMS
• Victron Battery Protects (2)
• Victron Lynx 1000 distributor
• Victron component networking via VE.Bus and VE.Direct communication buses. WiFi / Internet uplink to Victron VRM portal via CCGX
• AM Solar AMS control module for cold weather and other automatic system disconnects
• Inverter, battery, solar disconnects for manual manipulation / inclusion / exclusion of components from the system,
• New 120v panel and sub panels
• New 12v panel

[uncle_bob]

Originally Posted by wulfraat

Not enough data collected yet to share a statically significant sample / projection.. but VRM portal is logging all of my usage online so should be some good analytics to follow.

What I can tell you is that obviously, without the AirCon running the solar array of 8 panels will supply all DC needs without dipping into battery reserve during the day. That is a given. On a sunny day my panels push >40amps DC current at their peak . Cloudy day 50% of that. Overall yield on a sunny day is an awesome 4kwh or in the range of 250 DC amp hours supplied for energy consumption needs. That’s a lot of DC power kicked out by Mother Earth!

Now comes the AirCon - good ‘ol penguin II 15k unit..

AirCon with just a couple other small loads pulls~ 1800watts on a hot day. Like right now - 90 degrees outside - image below as I sit here in the heat (outside) with 13amp of shore power available and a 6pm cloudy sky overheard.

Some theoretical basic math....

Solar yield on a sunny day - 4kwh.
Battery capacity of 600ah with 20% reserve - 5.7kwh
Total power available in a sunny day - batt+solar - 9.7kwh

Penguin II 15k chews up and spits out 1800w - call it 2k watts with some other stuff going like our Ice maker, and no cycling of the compressor (super hot day). Screen shot below as I sit on shore power limited to 13amp output, supplemented by DC power via the hybrid inverter...

So 9.7/2 = 4.85 hours of non-stop running of the AirCon and other items with NO cycling of the compressor. Call it florida or Texas or Haiti heat!

So that is in theory. As I gleam data from the system combined based on my usage patterns and needs I’ll most definitely provide updates as I go along.

When push comes to shove I do have a little propane-converted honda 2000i that I can crank up to supplement (via power assist function in the victron multiPlus) another 1,500 watts constant if I really want to peg the AirCon for 8+ hours straight. I don’t like running the genset because it makes noise. I like peace and quite [emoji4] but I have it if I need it in Death Valley heat.

All that being said you’d need like 20 100watt panels to keep up with an AirCon running constantly and no compressor cycling. I only have 8 panels - so some power management is still needed so you don’t wake up the next morning with no reserve left [emoji4]

Hi

If we have our trailer out in the hot sun, and are on a single AC unit .... it will run for 8 to 10 hours straight. No shutdown of the compressor or fan at all. If it's really hot out and dripping humidity, it will not get the trailer below 85 degrees in mid afternoon while running that way. Unfortunately I *do* have data on this

If we move into the shade and maybe there's a bit of a breeze, indeed the single AC will do a fine job at a pretty modest duty cycle. Putting out the awnings helps as well.

Pull into a campsite after the trailer has gotten nice and toasty on the road. It takes a single AC a *long* time to get it down from near 100 degrees into the 70's. Turn on both units and it gets the trailer cooled down quite quickly. Oddly enough, you just might be able to run both AC units on a 30A plug. I ...errr .... also have data on this

How much it takes to "run AC" is very much a "that depends" sort of thing.

====

One *very* cute thing to do with the Victron Multi is to use the 13A of shore power you do have and let it make up the rest. That way you can pretty much go on forever and ever running the AC with a pretty modest system.

Bob

[wulfraat]

Heya Bob - I assume that when you state "run for 8-10 hours" that is with a small generator and the multi-plus working in assist mode to supplement the remaining power need with battery power?

With 600amp hours of batteries and 800w of solar at full output I could not run for the AC for 8 straight hours at a 100% duty cycle. AC on a hot day will draw 1800 watts...... that's about 80amps draw from the batteries if solar is pumping out full capacity.

[uncle_bob]

Originally Posted by wulfraat

Heya Bob - I assume that when you state "run for 8-10 hours" that is with a small generator and the multi-plus working in assist mode to supplement the remaining power need with battery power?

With 600amp hours of batteries and 800w of solar at full output I could not run for the AC for 8 straight hours at a 100% duty cycle. AC on a hot day will draw 1800 watts...... that's about 80amps draw from the batteries if solar is pumping out full capacity.

Hi

The "test condition" was a 30A plug in the Colonial Airstream lot . It was an insanely hot day in New Jersey when we took delivery. The single AC simply could not keep up. It thundered along running full time to about an hour before sunset. This was (obviously) long before I had the 400AH of Lithiums and the Multi.

What it *did* teach me (right up front) was the value of shade in a campsite. A bit further down the road and in the shade ( and with the ability to put out awnings) the same single AC did a very adequate job.

So is my test case "real world?" .... maybe not. There certainly are parking lots that you could be at on the gulf coast that make the test case look pretty trivial. Some of them supply shore power ....

Bob

[wulfraat]

Ah got it. Agree on shade if you have shore power not so good for solar

My fix is to camp high at 7 or 8,000 feet. Takes the edge off summer heat

[uncle_bob]

Originally Posted by wulfraat

Ah got it. Agree on shade if you have shore power not so good for solar

My fix is to camp high at 7 or 8,000 feet. Takes the edge off summer heat

Hi

Very few parts of the Jersey Shore make it to 8,000 feet

( for reference - the highest point east of the Mississippi is 6,684' ) It's rare to find a campground above 4,000' out here.

Bob

[JennyJakeNH]

Originally Posted by wulfraat

Heya slowmover.... I am still running dexter drum brakes on my 30' unit - works fine for me.

Regarding specs - I put a build description up in post #1 in this thread... here are the various system components that came together for this system:

• 800watts of solar - Eight (8) AM Solar SP100 panels up top. Ability to tilt if needed
• Victron 150/85 MPPT controller (Smart w/BT)
• Victron 12/3000 Multi-Plus inverter/charger with 50A pass-though
  • PowerControl (ability to deal with limited generator or shore power)
  • PowerAssist (ability to dynamically supplement the capacity of shore or generator power with batts)
  • Real-time uninterrupted 120v power supply when disconnecting shore / genset power sources
• Victron Lithium batteries (600ah total - 2 X 300ah batts)
• Victron CCGX monitoring panel with wi-fi and automatic upload to VRM portal
• Victron BMV-712 battery monitor (Smart w/BT)
• Victron Digital Control Center and BMV monitoring panel
• Victron BMS
• Victron Battery Protects (2)
• Victron Lynx 1000 distributor
• Victron component networking via VE.Bus and VE.Direct communication buses. WiFi / Internet uplink to Victron VRM portal via CCGX
• AM Solar AMS control module for cold weather and other automatic system disconnects
• Inverter, battery, solar disconnects for manual manipulation / inclusion / exclusion of components from the system,
• New 120v panel and sub panels
• New 12v panel

Hi Wulfraat - Great upgrades and great pics.

We are getting ready to do a series of similar upgrades to a 2019 30 FC Bunk. You pics and detailed bill of materials is awesome. Do you also happen to have a picture or two of the solar combiner box and the entry into the fridge vent? We've read Lewster's descriptions of similar installs in a few other posts, but actually seeing such an exact match to what we want to do would be a huge help.

Thanks in advance!

[wulfraat]

Unfortunately not. The photos I have of street side roofline just managed to cut it out of the frame! Doh!