2005 Roadtrek - no solar & no generator

[Fernando Damasceno]

Hello

I am looking for advice to run my appliances from a battery bank, charged by the vehicle alternator upgraded to 225A.
The RV is a Roadtrek, and there is no generator, and I don't want to use solar at this time.

The appliances would be:
- Induction cooktop 120V 1800W / Microwave
- AC pump heat
- LED lights / computer
- water pumps
I would like to be boondocking for 3 days.

What would be the size of the battery bank? Size of Inverter? wire gauge from alternator to the inverter?

Thank you!

[mkguitar]

Hi,

Welcome to the forums

You have set quite a challenge for yourself and this could be expensive.

Some who have experience can offer opinions

I too have an older RV and 5~7 days off grid are available to us- propane does the heavy energy ( fridge, water heater, furnace, 2 burner cook top)- our limiting factors seem to be fresh water, laundry or boredom- not energy

I have a genny but have never used camping- the only 120VAC devices we have are the microwave and air conditioning- we try to go where we don;t need ac!

our 12 volt dc requirements are low and a small solar panel I set out and kick to follow the sun tops up the single group 27 battery through the day


using Ohm's Law to calculate current draw, you cooktop alone requires 15 amp supply...using an large inverter to supply AC from a DC battery shows that more than 150 amp load will be placed on the battery ( plus whatever is wasted in the conversion process)-




cheers, Mike

[Fernando Damasceno]

Thank your for sharing your experience.

[booster]

Originally Posted by Fernando Damasceno

Thank your for sharing your experience.

I think you need to total up what your expected uses would be. It could vary a huge amount be how long they run, especially trying to heat with electricity. No propane in the unit? Propane for heat, hot water, and cooking could save a whole lot of money in batteries and equipment.


What model Roadtrek is it?


If you want to run all the stuff you listed, may guess is that you could be in to spending in the $10-20K range. I doubt that a 2205amp alternator would be able to keep up with all without an early failure because of lots of run time at high outputs. A second one would be needed.

[Fernando Damasceno]

Hi - Thanks for your answer. You are correct, Thermal energy via electricity, is not good for cars. So, I will pursuit the cooking, hotwater wit propane, and the alternator to all others electrical loads.
The RV is a 2005 RoadTrek Popular 190.

[themexicandoctor]

Excellent answers.

[ikanode]

You also need to get the specs for your air conditioner for it's start up amp draw. Your inverter may shutdown on AC startup even if the inverter is capable of handling the AC running load. So you need to match the inverter's surge rating with the AC's, plus the steady state ratings of both.

Consider an EasyStart added to your AC, it dramatically lowers the AC start up amp draw.

You will need to limit the number of items you run at the same time. Especially big loads like the microwave and AC.

[Macodiva]

Originally Posted by mkguitar

Hi,

Welcome to the forums

You have set quite a challenge for yourself and this could be expensive.

Some who have experience can offer opinions

I too have an older RV and 5~7 days off grid are available to us- propane does the heavy energy ( fridge, water heater, furnace, 2 burner cook top)- our limiting factors seem to be fresh water, laundry or boredom- not energy

I have a genny but have never used camping- the only 120VAC devices we have are the microwave and air conditioning- we try to go where we don;t need ac!

our 12 volt dc requirements are low and a small solar panel I set out and kick to follow the sun tops up the single group 27 battery through the day


using Ohm's Law to calculate current draw, you cooktop alone requires 15 amp supply...using an large inverter to supply AC from a DC battery shows that more than 150 amp load will be placed on the battery ( plus whatever is wasted in the conversion process)-




cheers, Mike

I have been wondering about a solar suitcase. So i can park in the shade & stick it out to get a little top up power. Totally no idea about solar & so many of the discussions here get me more confused lol! So my simple & possibly daft question is, what do you need & how do you get the power from the solar to your battery? I'd assume you just plug in something somewhere?
Thanks

[andrewtschneider]

Originally Posted by Fernando Damasceno

Hello

I am looking for advice to run my appliances from a battery bank, charged by the vehicle alternator upgraded to 225A.
The RV is a Roadtrek, and there is no generator, and I don't want to use solar at this time.

The appliances would be:
- Induction cooktop 120V 1800W / Microwave
- AC pump heat
- LED lights / computer
- water pumps
I would like to be boondocking for 3 days.

What would be the size of the battery bank? Size of Inverter? wire gauge from alternator to the inverter?

Thank you!

I strongly suggest you consider solar as part of your total solution. I installed a Renogy DCC50S 12V 50A DC-DC ON-BOARD BATTERY CHARGER WITH MPPT in my van. It can charge both the van and house batteries from solar and it allows me to an option to use any type of battery. I also recommend an Victron BMV-712 battery monitor. It will allow you to see what is going in and coming out of the battery. Monitoring it teaches you how to 'live within your means'. Much as I hate to say it, Propane is incredibly efficient and is a better for cooking, hot water, and heat. Induction cooking looks sweet, if you have a large battery bank. We never use A/C or our generator. But it is nice to have the option. Good luck.

[Luv2Go]

Adding A/C to the mix adds a ton to the inverter sizing and the battery usage. To give you an idea, I have a 3KW pure sine wave inverter and 320A/H of LFP batteries (that can be drained to almost 0% and not lose significant life). Running the A/C for two hours straight drains the batteries to 20%. This is the standard Dometic A/C that the '05 and '06 Roadtreks have. Upon further review it looks like you are using the A/C for heat and you'll use the furnace for that, good decision.

Without the A/C now all you have is the Microwave as a big user. That takes relatively little energy, though it takes a lot of power. I was able to run the microwave (the Samsung Toaster Microwave that comes with the '06) with a cheap Pure Sine wave 2000W inverter, just barely. You can probably get away with two 6V golf cart batteries (our 210 came with them, not sure about your 190), though you'll have to increase the size of the cables to whatever the inverter manufacturer recommends (usually 2/0 for runs of up to 5'). Remember to increase the size of the cable between the batteries too.

If you nix the microwave usage you'll probably find that the original battery/batteries you have in your Roadtrek will work well since you have changed lighting to LED. The computer can be powered by a relatively small inverter, the one that came with our Roadtrek (a 650W modified sine wave) worked for our computers, though I prefer and now use a pure sine wave.

Note to boondock for three days you may find you'll need more than the two golf cart batteries. Calculating your usage as suggested in earlier posts will give you an idea. There are many RV energy usage calculators on the net, here's one example.

The BMV712 is a great monitor, if you don't like the price there are cheaper ones available like the Thornwave PowerMon or the new 5S that comes with a 500A shunt, both are cheaper than the Victron (I have and like both). They have no built in display, so are less trouble to install but also need the phone app to use because of that.

Also lead acid batteries should not routinely be discharged 100%. The amount varies by who you believe but it's in the 50% to 80% range. This must be taken into account when you size batteries. There's a lot more to learn about care and feeding of lead acid batteries, do an internet search and you'll find lots of opinions and methods, some of which directly contradict each other.

[Luv2Go]

Originally Posted by Macodiva

I have been wondering about a solar suitcase. So i can park in the shade & stick it out to get a little top up power. Totally no idea about solar & so many of the discussions here get me more confused lol! So my simple & possibly daft question is, what do you need & how do you get the power from the solar to your battery? I'd assume you just plug in something somewhere?
Thanks

If you don't get any response you may want to start a new thread with your question. This thread is dealing with a different topic, the OP does not want solar at this time.

[Fernando Damasceno]

Thanks you for your recommendation. I appreciate it.

[Fernando Damasceno]

Thanks you for your recommendation. I appreciate the idea of Solar combination.