New E21 Boondock Ready(5.1KwH solar system)

[TexanAviator]

Originally Posted by rubicon327

I'm curious as well, but will contend that you are doing this for capability not an ROI. The costs are still just too high. For perspective the closest system from AM Solar is $6,250 for materials only or $12,230 installed with 46 hours labor ($130/hr).
https://amsolar.com/rv-complete-solar-systems/99-trlslv

Would this system be the best bet for a 5.0 if I want to be able to run the fridge, water heater, convection microwave, and AC with a soft starter? I'm also toying with the idea of doing an induction cooktop to not need propane.

[E Ticket]

Hello TexanAviator,

That would be a stretch. To give you an Idea, I just finished a 3 day dry camping trip in Joshua Tree National park with 8 rock climbing friends. 4 people stayed inside and the rest were on tents. But all the food prep was using my E21. For all three meals, we used a 1000W microwave, 500W mini toaster, a 100W portable fridge plugged in outside a 1300W Nespresso machine and a milk frother for coffee. All the lights were on during the evenings and cell phones were charging overnight. I started out with 93% soc on my battery bank. The solar panels produced 1.8kwh on Sunday and 1.85kwh on Monday. THe lowest soc on the battery during the entire outing was 49%. We were very liberal about the use of electricity. However, my fridge and water heater was on propane.

I think you would need more than 5.1kwh battery bank and more solar panels to do what you want to do. For me, the fact that I did not have to have a generator to do the things I wanted this last trip made it worthwhile for me and for ROI. This trip, the black and grey tanks were my challenge in accommodating 8 people using the John and the sink, but not the fresh water. My new 20 gal axillary water tank, plus my truck bed 30gal bladder tank made fresh water supply a non-issue. The truck bed 30 Gal came back full.

[TexanAviator]

E Ticket,

Thank you for the response! Which of the AM solar setups do you think I should go with?

[Defenestrator]

Originally Posted by TexanAviator

Would this system be the best bet for a 5.0 if I want to be able to run the fridge, water heater, convection microwave, and AC with a soft starter? I'm also toying with the idea of doing an induction cooktop to not need propane.

Definitely not nearly enough for all that. Propane is way, way more energy-dense than batteries. To put it in perspective, if my math is right the two propane tanks on the tongue are the equivalent of about 21,000Ah of batteries. About 100x the specific energy.

The microwave, Nespresso, and toaster actually aren't all that bad to power. They need a ton of power, but only for a few minutes a day. The AMSolar setup linked would probably handle that on a cloudy day without a problem. Induction cooktop will take a larger chunk out of it depending on how long you run it, but still doable unless you're making a big pot of chili or something.

The absorption fridge built in won't work well on batteries+solar at all. It's atrociously inefficient compared to a compressor fridge (about 4-10x more power for the same cooling). That alone would empty the battery pack overnight. A compressor fridge is 5-10x better and might work OK, but combined with all that other stuff it's still going to be cutting it close at best.

Climate control is the hardest part. That 200Ah battery pack gets you 1-2hrs of air conditioner with nothing else drawing power, or maybe a few minutes when combined with all the other stuff. A standard electric resistive heater's going to be pretty similar - a couple hours tops and you're empty. A heat pump will do better, but those tend to have fairly high minimum exterior temperatures (30-40F).

The water heater falls into the same bucket as climate control - far, far more energy than you can gather via solar that fits on a travel trailer, and far more than you can store in a reasonable battery bank.

[Defenestrator]

To do without propane entirely and still have hot water and air conditioning, you'd basically have to fill every storage space on the 5.0TA with batteries - about 40 of them, weighing around 1200lbs in total. You'll also need far more solar than you can fit on the roof - probably at least double the total roof area even ignoring space eaten by vents etc.

I have 360W of solar and 500Ah of LiFePo4 batteries. It's enough battery to run the A/C for probably 2-4 hours plus assorted other needs, though the solar will replenish maybe half that on a good day. I rarely run the fridge in electric mode (sometimes on a sunny day if I'm traveling to someplace that has hookups so I don't care about running the battery down a bit. Basically, if I'm sure I have power to spare or while I'm filling with gas), and I've never bothered trying to run the electric water heater off of batteries. Same with heat - it's plenty to power the furnace fan, but not enough to run an electric heater long enough to matter.

[E Ticket]

Hello Defenestrator,

That's quite a battery bank you have. I assume you have a 12v system.

On a side note, my house lifepo4 battery bank of 96 CALB 72ah, 22.2kwh for my house are only 384lbs. That banks runs my entire home minus the 5 ton AC. But I do have a 12000btu window unit that I can run for quite awhile. Cycling on and off. So 1200lbs of lifepo4 would be 3x of what I got. And that would run a few 5.0's

[IMG][/IMG]

[E Ticket]

[IMG][/IMG]

[E Ticket]

My 5.1kwh bank is only 96 lbs or so.

[Defenestrator]

Yep, 12V.

1200lbs is maybe on the upper side, but not that far off. That window unit's probably a bit more efficient than the RV rooftop units, and I think the duty cycle on the electric water heater tends to be pretty high. So, 400lbs for the AC, 600 for the water heater, 200 for everything else combined. That's assuming some padding for overcast days and such as well. You could probably get by with less, but you'd either need grid power or a generator to fall back on for days that aren't cool and sunny or be prepared for some hot days and cold showers. I was also going off of Battleborns, but it sounds like your setup knocks about a quarter off the weight by comparison.

That's quite the home setup! Handy for the power cutoffs, I imagine.

We lost power for 18hrs or so where I am now (Rio Vista) and I had the neighbor plugged into me for a couple hours to charge their batteries. Not much solar because we're in the shade, but the battery bank was plenty for lights, furnace fan, and misc stuff without really putting a dent in it.

[BobG]

E Ticket, I have 2 questions:



Why switch from 12v battery to 24v and then back to 12v to run 12v lights, fans, pumps, and other equipment? I probably missed something but if not, is there that much voltage loss in wiring or that much weight increase in wiring staying with 12v, to make up for loss of converting voltages.


Second question is that 12v 100Ah is $360 from Alibaba and $900+ on Amazon Battle Born.. I understand you got batteries for $600+ somewhere else.


This is quite a difference in price. Did you investigate why the difference? Maybe different battery form factor or? It is $1,000+ to $2,000+ savings buying from Alibaba.


https://www.alibaba.com/product-deta...B#shopping-ads


https://www.amazon.com/LiFePO4-Volt-...a-571575372143

[godspeed]

Love your system! Amazing. What are you doing that you require so much solar, lipo batteries and a 3000 watt inverter? Are you running your fridge on batteries as well? I have a 2018 21' and 200 watts of solar and the 1500 watt inverter from ETI which has been great for coffee, working on the road with our computers, water pump and TV/DVD use. My next upgrade will be lithium batteries. When we have 3 or 4 days of gray weather my 2X6 volt AGM batteries struggle. Thanks for sharing.

[Defenestrator]

It's really just a single conversion from 24V to 12V. The inverter etc run off of 24V directly, so no conversion there. That means the high-current stuff (inverter and charger) are 24V and it's just the misc stuff like lights and pump that are 12V.
The inverter can do up to 6000W for short bursts, which at 12V would be 500A. That's an absolutely massive amount of current.

The Alibaba batteries, from what I've heard, are... varying.. in quality. That is, instead of being 100Ah of LiFePo4 it may well be 100Ah of NMC or NCA, or even more like 20Ah of batteries labeled as 100Ah.

[E Ticket]

Originally Posted by TexanAviator

E Ticket,

Thank you for the response! Which of the AM solar setups do you think I should go with?

Hello TexanAviator,

That's hard to say. Sorry it's not the answer you are looking for. There are lots of design considerations. I started with a list of needs and followed by some wants. I compared the cost and started massaging the list and added some wants and nice to have and came up with what I have now.

The 5.0 definitely has a lot of roof real estate to work with. However, it is still a smaller than traditional 5th wheel design. I am just guessing that you can work with 160 to 200W panels depending on the respective geometries of the panels to get the most out of the space you have. A wild guess with having a roof AC and a vent on the 5.0, you might be able to squeeze in 800 to 1000 watts on the roof.

Be aware that the panels rating is not real world output. for example, expect average of 65-70% peak output from these panels, with about 85% peak of the rated output in dead of summer at perfect sun angle. For example, my 520w setup was peaked at 375w on a bright Oct day here in So Cal. I produced about 1.87kwh from these 2 panels while out in the dessert Monday.

Also, consider real world environment. For example, my Victron 300oW inverter spec'ed 3000W continuous output at 25C (77F), however, it is derated to 2200W continuous output at 40C (104F). In most RV application, the inverters are shoehorned into small spaces tucked in some not so favorable environment with air circulation challenges. Hence, my selection of the 3000W over the 2000W inverter. Furthermore, there will be times when my daughter decides to warm her muffin in the microwave while blow drying her hair. I wouldn't have to worry about over-current shutdown nuisance with my setup.

I know that I over designed my system with 5.1kwh bank and 3Kw inverter, but I like the buffer and margin in this RV application.

The other day, i set the Tstat on the E21 AC to 79F while the outside was toasty 95F during one of the SoCal October Santa Ana heat wave. My E21 was already heat soaked. The AC cycled from 11am to 5pm and kept the temperature down at setpoint. Battery started at 94% and was down to 67% by the evening. My battery contributed 1377 watt hour to the AC and the 1500 watts hour came from the panel during that same period. Total output of 2877 watt hour for the hungry AC. My Dometic 11000btu consumes about 1180 watts per hour. So, the AC run total of about 2.4 hours during the 6 hour period. Not bad for me in SoCal condition. I can not say that my system would work for the Texas summer. If I were in the beautiful state of Texas, I would have 2 more large panels above my truck bed to offset the Texas summer humidity, and would invest in a min-split for better efficiency.

Good luck.

Johnny

[godspeed]

Great advice Johnny! Thanks for sharing!

[E Ticket]

Originally Posted by BobG

E Ticket, I have 2 questions:



Why switch from 12v battery to 24v and then back to 12v to run 12v lights, fans, pumps, and other equipment? I probably missed something but if not, is there that much voltage loss in wiring or that much weight increase in wiring staying with 12v, to make up for loss of converting voltages.


Second question is that 12v 100Ah is $360 from Alibaba and $900+ on Amazon Battle Born.. I understand you got batteries for $600+ somewhere else.


This is quite a difference in price. Did you investigate why the difference? Maybe different battery form factor or? It is $1,000+ to $2,000+ savings buying from Alibaba.


https://www.alibaba.com/product-deta...B#shopping-ads


https://www.amazon.com/LiFePO4-Volt-...a-571575372143

HI BobG,

looked like your question was addressed. But adding to that. It was my original intention to have a 48V system for even better efficiency. But unfortunately, many of the 48V inverter has more home features than I need. So I stepped down to the 24V inverter. I could easy have gone to the 12V bank, as my individual lithium cell can be rearrange to any bank voltage. I already have 34V solar panels that i wanted to hook up in series on my E21 roof. Although the Victron MPPT is 98% efficient ( as stated), Logically for me, that stepping down the 68V solar to the 12V was a large step-down in my head and that 68V to 24V made more sense for me. But that's not the major considering. It was the large current flow from the bank that was my consideration like the other gentleman mentioned. 3000W/12V is 250A vs 3000W/24 is only 125A.

As for my battery selection, I have had good personal experience with this brand of battery. I bought 16, 3.2V 100Ah paying $115ea plus $200 for shipping. My setup is equivalent to 4 x 12V 100Ah batteries. So I am paying $510 for one equivalent 12V, 100Ah battery. These are rated for 3000 cycles (0 to 100%) with 80% or greater capacity after that.

I also like the form factor of my battery as they are 5.5"L x 1.6"W X 12"H. I can minimize and optimize battery foot print as they are easily arranged. since the E21 dinette bench storage height is about 13 or 14" height, it's perfect for going high instead of wide as in the battle born form factor.

Good luck with which ever battery choice you select.

[rubicon327]

Originally Posted by Defenestrator

Climate control is the hardest part. That 200Ah battery pack gets you 1-2hrs of air conditioner with nothing else drawing power, or maybe a few minutes when combined with all the other stuff. A standard electric resistive heater's going to be pretty similar - a couple hours tops and you're empty. A heat pump will do better, but those tend to have fairly high minimum exterior temperatures (30-40F).

I’m excited when others mention heat pumps because I’m already outfitted with the Fujitsu 9RL2 that would draw only 580W or so in economy mode (cooling). It can run in heating mode down to 15F but I’m sure capacity is reduced. The best test I ran was at about 23F outdoors at start and 19F by the end as sun had gone down. Over a two hour period the trailer was heated from ~25F up to 60F. I found this quite impressive given that the unit is rated nominal 10,000 BTUH at 47F outdoor temperature. The furnace is still the primary heat source.

[rubicon327]

Originally Posted by E Ticket

My Dometic 11000btu consumes about 1180 watts per hour. So, the AC run total of about 2.4 hours during the 6 hour period. Not bad for me in SoCal condition. I can not say that my system would work for the Texas summer. If I were in the beautiful state of Texas, I would have 2 more large panels above my truck bed to offset the Texas summer humidity, and would invest in a mini-split for better efficiency.

Johnny: If my 9,000 BTU Fujitsu 9RL2 mini-split draws 580W in economy cooling mode compared to your Dometic 11K BTU rooftop at 1180W then would it essentially be a doubling of the possible run time? I know actual output and cycle time would affect this.

[E Ticket]

Hi Rubicon327,

Your Fujitsu is certainly very efficient over any RV AC. Drawing only 580 watts is amazing for an AC system. I understand that there are inverter type mini-splits that can have SEER rating as high as 30 SEER or more. Accounting for conversion lost and efficiency consideration, i would multiply the 580W by factor of 1.2 for calculations. So expect to draw 696wh coming from your battery to power the Fujitsu. With the example of my system of 5.1kwh bank, I would allocate 85% SOC for use and leave 15% SOC for safety and battery longevity. So .85 x 5.1kwh = 4335wh. You can then run your Fujitsu for 6.2 hours at 100% duty cycle (4335Wh/696Wh) or 12.4 hours for 50% duty cycles. But that's just an estimate. Real world situation will vary.

[TexanAviator]

E Ticket, are these mini splits ever done from the factory?

[Brian B-P]

Originally Posted by TexanAviator

... are these mini splits ever done from the factory?

I'm pretty sure that the Escape factory has never installed an air conditioner other than their standard offering, and although none of us can speak for them, I would be very surprised if they would seriously consider installing any unit which does not mount in the standard 14x14 ceiling opening.

Split A/C systems are used in other types of vehicles, such as truck cabs and heavy equipment, but they're specifically built for use in vehicles.

I like the residential mini-split idea, and Dave (rubicon327) has done most of work of sorting out Escape installations, but it's still a do-it-yourself project rather than a factory customization or commercially provided upgrade.