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What’s a better plan, 24v direct or 24v inverted to 110v? Similar to an RV set up.

BattleAxe

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I’m starting process of building an off grid camp, I plan to set up a 24volt battery bank with solar to charge/maintain and I will also have a gasoline powered 9,500KW inverter generator to run, ac units microwaves etc as needed. MY question is should I wire the camp up like an RV with some DC powered lights, exhaust fans, phone chargers etc and then wire outlets etc for 110, to run TV, microwave, AC unit etc. OR
would
Running EVERYTHING through the inverter and not having any 24v dc lights etc. not make enough difference to matter?
Will I get better performance with separating the lights, fans, chargers etc to DC and not running them through an inverter?

Example if I need 200 watts of power to run lights, fans etc. would It be better to run 24volts dc to 24 volt dc items or convert/invert that 24 volts to 120ac to run the same wattage 120ac items. How much will I lose or gain with these options?

Any help is appreciated.
 
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The dc distribution system is 12 volts.
Finding 24 volt DC stuff is a challenge.
24 volts is not as bad for voltage drop but its still a concern.
Have you considered a 48 volt system with a split phase inverter/charger?
 
There's always an efficiency loss going from DC -> AC -> DC. So you will always get better performance running DC loads directly from the battery when it makes sense. You could get 10%-20% more use out of your batteries for the DC-only loads versus running those same loads through the inverter. But the gains may be lowered slightly if you need to add a 24V->12V DC-DC buck converter to run 12VDC loads from the 24V battery.

Keep an eye out for TVs that can be run from DC directly.

In the end though, if your AC loads through the inverter are a vast majority of your power needs, the savings for a few lights/fans/etc. may not be worth the effort. It might be better to add an additional solar panel or two instead.
 
The dc distribution system is 12 volts.
Finding 24 volt DC stuff is a challenge.
24 volts is not as bad for voltage drop but its still a concern.
Have you considered a 48 volt system with a split phase inverter/charger?
Have not considered 48volts. I’ve been able to find plenty of lighting, a few fans etc that will run on 24v and figured I’d step down to 12v for things I couldn’t find in 24v.
 
Have not considered 48volts. I’ve been able to find plenty of lighting, a few fans etc that will run on 24v and figured I’d step down to 12v for things I couldn’t find in 24v.
What about split phase 120/240VAC?
You can also step down from 48 to 12 volts.
Will you have 1 building or >1 buildings.
How big and how far apart?
 
There's always an efficiency loss going from DC -> AC -> DC. So you will always get better performance running DC loads directly from the battery when it makes sense. You could get 10%-20% more use out of your batteries for the DC-only loads versus running those same loads through the inverter. But the gains may be lowered slightly if you need to add a 24V->12V DC-DC buck converter to run 12VDC loads from the 24V battery.

Keep an eye out for TVs that can be run from DC directly.

In the end though, if your AC loads through the inverter are a vast majority of your power needs, the savings for a few lights/fans/etc. may not be worth the effort. It might be better to add an additional solar panel or two instead.
Thank you!!
In my camper I typically get through most of the time just running off the battery and then (no solar) charging batteries with a small generator/inverter. Most of my time will be spent at the camp in the cooler months of the year and will not need to run the generator very much. So I guess I need to figure out the math if the juice is worth the squeeze in running a separate DC wiring set up for those items listed.
 
What about split phase 120/240VAC?
You can also step down from 48 to 12 volts.
Will you have 1 building or >1 buildings.
How big and how far apart?
Well, my electrical literacy at this point is too poor to have an proper response to that. However maybe I need to study that.
 
Another way to ask my question is why 24 volts as opposed to 12 or 48?
Well I focused in on 24 to reduce my amps as apposed to 12. But moving to a 48v system would cost that much more in batteries. So I’m trying to control costs and get by on my limited knowledge.
Thanks for your patience, I’m trying to figure all this out and I really appreciate your engagement.
 
But moving to a 48v system would cost that much more in batteries.
Not really. If you were planning a 24V 200Ah battery bank, for example, then you could instead go with a 48V 100Ah battery. It's the same total watt hours and it should cost roughly the same. But now you can use smaller charge controllers (cheaper) for a given amount of solar, and smaller wires (cheaper).
 
Power transmission over any distance is a important consideration.

10 amps at 12 volts = 120 watts
5 amps at 24 volts = 120 watts
2.5 amps at 48 volts = 120 watts
1 amp at 120 volts = 120 watts
.5 amps at 240 volts = 120 watts

This web application will let you explore how distance, current and voltage effect voltage drop.
 
Also I remember watching on of Will’s videos and him talking about 48v can get dangerous? Is that correct or is that after you get up to around 50? Something about enough volts to stop your heart or something?
 
Also I remember watching on of Will’s videos and him talking about 48v can get dangerous? Is that correct or is that after you get up to around 50? Something about enough volts to stop your heart or something?
Its more dangerous than 12 or 24 volts.
I can't really quantify how much more.
I got a tingle on my sweaty arm touching the positive busbar while my arm rested across the inverter chassis of my 24 volt system.
I treat 24 volts with more respect now.
 
MY question is should I wire the camp up like an RV with some DC powered lights, exhaust fans, phone chargers etc
For your 120VAC whether 24V or 48V how many panels (wattage) are you planning?

The efficiency of 12V devices makes no sense to me converted from 24- or 48V.

What *I* recommend is set up your 24 or 48V system for AC. Ignore DC appliance/device usage. You’re going to spend a few thousand- do it well.

Then spend $175 on 200W of panels, $65 on the little Epever charge controller, $60 on a 300W pure sine inverter, and $200 on a pair of walmartha marine deep cycle batteries. Wire 12V lights and chargers and have lights and convenience emergency small 120V/~3A even if the main system goes down.

12V is convenient and handy imho but I like independence/redundancy for lights in an emergency or whatever
 
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