Newbie Wanting to Upgrade to Lithium AND add more solar...

[Zap-Ouch!]

My goal:

Replace my lead acid battery with lithium in the range of 400 - 460ah. We plan on doing a good amount of boondocking, so I want to be able to survive on the battery power as much as possible and only rely on the generator when needed (to charge the battery on cloudy days and to run the AC, etc).
I'd like to be able to have battery power for up to 3 days at a time.
** I will be installing a Soft Start on the AC **

Things I would want to power:
Furnace, TV, Microwave, coffee machine, blow dryer, laptop computer, Starlink, Cellular wifi/modem,
space heater, dehumidifier, phone chargers, electric blanket and other misc., low draw/watt items.

My rig: 2024 Jayco Jay Feather 21MML travel trailer.

Equipped with:
30 Amp GoPower PWM Solar Controller (GP-SB-PWM-30BT)
* Lithium battery option

A single 200w panel (with the intention to add another couple of 200W panels, which is what the charge controller can handle)

WFCO Converter (WF-8560-AD)

* Lithium battery adaptability

Generator: Firman WHO3242 Dual Fuel, Inverter Generator. 3200w /4000w.

Questions:

Is a 400 - 460ah battery overkill based on the above?

Do I need a combo inverter/ charger? If so, how many watts? I was thinking in the 3000 watt range as I wanted to have room to maybe expand the system in the future.

And if I go with inverter / charger, would I no longer need our converter for battery charging?

I totally want to do the upgrade myself, as such, I would appreciate any DIY links.

Thanks in advance!

Glen

 

[DIYrich]

A single 200w panel.

That's your immediate problem. You would be lucky to get 1kWh from the panel on a good day.

 

[Zap-Ouch!]

That's your immediate problem. You would be lucky to get 1kWh from the panel on a good day.

My intention is to add another 2 200W panels. At least to start.

 

[DIYrich]

My intention is to add another 2 200W panels. At least to start.

How many kWh do you need per day?

 

[Zap-Ouch!]

How many kWh do you need per day?

So I used an online calculator on Boundless PS entitled "electrical-load-calculator". It used "amp hours" as the measurement.
Here were the results:
78.27 daily ah (12v usage) and 172.72 daily ah (120V) usage for a total of 250.81 DC losses. According to the calculation, if I used 600 watts of panels and assuming 5.83 hrs of sunlight, there would be 273.28 ah of dc gain.

I hope that's enough info to help me answer the questions in my original post. I sincerely appreciate you thoughts on this.

 

[MisterSandals]

It used "amp hours" as the measurement.

Amps and amp hours are not useful without the voltage.

78.27 daily ah (12v usage)

78Ah x 12.8V nominal = 998Wh (1kWh)

172.72 daily ah (120V) usage

172Ah x 120V = (surely you mean something else!)

172Ah x 12.8V = 2200Wh (2.2kWh)

Ising an inverter: 2.2kWh / .85 efficiency = 2.59kWh

1kWh + 2.59kWh = 3.59kWh total daily

To harvest this much solar in a 5h day:
3590Wh / 5 = 718W solar panels

 

[MisterSandals]

Things I would want to power:
Furnace, TV, Microwave, coffee machine, blow dryer, laptop computer, Starlink, Cellular wifi/modem,
space heater, dehumidifier, phone chargers, electric blanket and other misc., low draw/watt items.

I'd be mighty curious to see the power calculations on all this stuff. Most of it is pretty outrageous for a boon docking scenario without a ginormous array and battery.

I did a quick search and found : On average, the Standard Starlink square dish and hardware uses 45-75 watts.
60W x24h = 1440Wh (more than a third of your daily estimate)

Microwave 1500W x 30 min = 750Wh

Furnace, space heater and electric blanket? waaaaa?

I don't see any possible way your daily use of all these items uses only 3500Wh.

Can you post the details of the electrical-load-calculator you used? Something seems way off.

 

[Zap-Ouch!]

Amps and amp hours are not useful without the voltage.


78Ah x 12.8V nominal = 998Wh (1kWh)

172Ah x 120V = (surely you mean something else!)

172Ah x 12.8V = 2200Wh (2.2kWh)

Ising an inverter: 2.2kWh / .85 efficiency = 2.59kWh

1kWh + 2.59kWh = 3.59kWh total daily

To harvest this much solar in a 5h day:
3590Wh / 5 = 718W solar panels

Calculator: https://www.boundless-ps.com/reference/electrical-load-calculator/

Yeah, I may have entered some things incorrectly in the calculator.

Obviously, many of the items would not be running simultaneously such as the furnace, space heater, electric blanket (fine... no blanket). ;-)

Here are the electronics/appliances:

Furnace: 144w
Water pump: 84w (7amp)
Hair dryer: 1500w
Space heater: 1500w
Refrigerator (12v): 1.08 kwh per day (says 3 amps in the rv's general manual, but that seems low to me)
TV: 200w
Laptop: 50w
2 tablets, 2 iPhones that would require daily charging: ???w
Dehumidifier: 60w
Lights (LED): 125w
Tankless Water heater: 20w (?)
Coffee Maker: 1200w (10amp)

 

[MisterSandals]

the furnace, space heater, electric blanket (fine... no blanket). ;-)

I don't care, you can run A/C too and i'm good with that.

Furnace: 144w
Water pump: 84w (7amp)
Hair dryer: 1500w
Space heater: 1500w
Refrigerator (12v): 1.08 kwh per day (says 3 amps in the rv's general manual, but that seems low to me)
TV: 200w
Laptop: 50w
2 tablets, 2 iPhones that would require daily charging: ???w
Dehumidifier: 60w
Lights (LED): 125w
Tankless Water heater: 20w (?)
Coffee Maker: 1200w (10amp)

So how many hours or minutes for each of these each a day? If you're building a system, you need to figure out what its supposed to do (hopefully on the first or second try, this gets expensive getting it wrong).

 

[Zap-Ouch!]

I don't care, you can run A/C too and i'm good with that.


So how many hours or minutes for each of these each a day? If you're building a system, you need to figure out what its supposed to do (hopefully on the first or second try, this gets expensive getting it wrong).

OK, good advice. Thank you. It seems like running the AC would require a lot more money, equipment and weight compared to what a generator could offer (with an soft start on the AC). So, my thought was to just focus on all of the other appliances/electronics. So, I will figure out the estimated hrs/min. of each item. Since we have a bunch of scheduled outings this year (our first full year of rv'ing), I will monitor actual usage. I'm sure the results will be eye-opening. Sorry for the run-around, but - like most humans - I was hoping for a cookie-cutter answer, but I now realize we're dealing with a rubber yardstick - everyone's needs are different. Your input has been greatly appreciated! Have a great weekend!