Submitted: Wednesday, Jun 11, 2014 at 19:07
ThreadID: 108218 Views:2869 Replies:4 FollowUps:5
This Thread has been Archived
Ok so this is prob dumb question of the week but if I put in an inverter and extra battery in my to get 240v for some appliances eg air con microwave and recharging computer without using a generator does etc does that then mean all appliances will then need to be :240v . Presently all lights are. 12 v. Tv and fridge when connected to care. Excuse my lack of understanding but we are are trying to decide whether to get to get a generator which can be noisy and annoying or get extra solar and battery with inverter .
Back Expand Un-Read 0 Moderator

Reply By: Motherhen - Wednesday, Jun 11, 2014 at 19:28

Wednesday, Jun 11, 2014 at 19:28
The air conditioner and/or microwave would be too much for a regular solar powered battery bank. With an inverter you can run 240 v items direct, and 12 v will still continue to run 12 v items.

We have four 130 w panels and 4 110 ah batteries, and this is more than enough for 12 v fridge, pumps, computers, and small 12 v appliances. We would not consider a microwave or air conditioner from this supply.


Red desert dreaming

Lifetime Member
My Profile  My Blog  Send Message

AnswerID: 534200

Reply By: Member - John and Val - Wednesday, Jun 11, 2014 at 19:52

Wednesday, Jun 11, 2014 at 19:52
With a simple battery based system you do not have enough energy to run air con, microwave etc. You should be able to find a 12V power supply to charge your computer, although a small inverter could be used for this too.

The straight answer to your question is that you could run some gear on 240V using an inverter while running other stuff on 12V. The limiting factor is the amount of energy you require, not the available voltage. More efficient if you can run all the essentials on 12V

You might find Electricity for Camping a useful read.


J and V
"Not everything that can be counted counts, and not everything that counts can be counted."
- Albert Einstein

Lifetime Member
My Profile  My Blog  Send Message

AnswerID: 534201

Reply By: wholehog - Wednesday, Jun 11, 2014 at 20:08

Wednesday, Jun 11, 2014 at 20:08
If you have a good and good capacity solar, battery storage system and inverter, you will run most things like microwave, toaster, heater fan, but NOT an air conditioner.

The only time a generator will be annoying is if you buy a cheap POS.

When camping/travelling, time is free, spend it cooking outside, use gas or fire and enjoy where your have travelled to.

If you don't/won't invest in a good solar/battery setup, then buy a nice generator, a quality one, please.
AnswerID: 534205

Follow Up By: The Bantam - Wednesday, Jun 11, 2014 at 22:41

Wednesday, Jun 11, 2014 at 22:41
Oh please...running a toaster and heater off an inverter....that is just rediculous.

Its not too hard to buy an inverter that is capable of supplying the heavy currents that heating appliances demand....but they will flatten any battery you want to pay for pretty quick smart.

The microwave is a marginal item.....they are a high demand item , but in general they run for a short time.

The single most imporatant thing is to stop thinking like you are at home on a mans supply.

Remember a 12 volt inverter draws 20 times the current from the battery that the appliance demands.
A item that draws 7.5 amps at 240V is a trivial demand on household via an inverter from a 12 volt battery it will be drawing 150 amps..pluss conversion losses.....that is hammering any battery supply.

Forget electricity for any heating function.

As for the the home on 240V they are quick clean and convienient.....well they appear that way....truth is teven in the home there are faster and more efficient ways to do stff that people do in the microwave......away from a 240v supply they become less and less viable.

with all the great 12 volt items on the market now...there is less and less reason to have 240v supply in a caravan other than for charging the batteries or running the airconditioning....when on a mains site.

Most small TV's are 12 volt native these days as are many other items of electronics.

FollowupID: 817805

Follow Up By: wholehog - Thursday, Jun 12, 2014 at 08:05

Thursday, Jun 12, 2014 at 08:05
Bantam, Hopefully people look beyond a cheap 60 watt panel, a 420cca start battery and a small chinese inverter when using solar as the primary energy supply.

I think your last sentence starts to show some sense ..
"with all the great 12 volt items on the market now...there is less and less reason to have 240v supply in a caravan other than for charging the batteries or running the airconditioning....when on a mains site."

Back to the toaster and heater......You may need to get out and see whats available and useable in a quality solar/storage setup these days.

FollowupID: 817818

Follow Up By: The Bantam - Thursday, Jun 12, 2014 at 20:44

Thursday, Jun 12, 2014 at 20:44
No matter what size battery or inverter you have running or what technology you use a toaster or room heater off 12 volts is rediculous.

Even heating using 240v from a grid connected supply is inefficient, wastefull and gutless.

moving heating with electricity from a 240V grid connect situation to running off batteries moves it from being marginally viable to being rediculous.

Electricity simply can not compete with burning something for outright thermal capacity and most importantly for energy storage density.

Go do the out the size battery bank you would have to carry just to compare with a single disposable butane can...then move that up to a 9Kg gass cylinder.

most people we have post here have barely enough battery capacity to keep up with their fridges.,

a battery that would happliy run a 40 litre fridge for three days would be flattened ( dead flat) in less than 30 minutes running a typical 2400 watt heater.

then think about the expense in inverters and chargers required to support such a load for more than a hour or two.....rediculous when compared to producing the same heating or greater heating capacity from gas.

I have a couple of those $20 butane stoves......They are cheap and nasty compared to good quality gas equipment...but they make my electric stove in our house look gutless.

Please people don't even think about heating anything from a 12 volt is a very expensive fools erand.

FollowupID: 817853

Reply By: ozwildlifecarer - Thursday, Jun 12, 2014 at 07:33

Thursday, Jun 12, 2014 at 07:33
Thanx everyone. I didn't want to run everything on 240v. Was just told by another camper they had 2 batteries with an inverter and extra solar and they used to run their 240 v appliances eg aircon microwave. Yep hate microwave but came in van. Also hate aircond but told will need it for cooling and heat up nth . Just trying to work out best way to run them. I need to use my computer and know the normal inverter you buy for car drains even car battery so concerned about it draining my caravan battery. I have a mac book air and finding a charger for that has been difficult . A suggestion on that would be good too.
AnswerID: 534224

Follow Up By: wholehog - Thursday, Jun 12, 2014 at 08:13

Thursday, Jun 12, 2014 at 08:13
ozwildlifecarer, 2 batteries isn't going to give you much duration, you'll kill them too easily on large capacity appliances.

I hardly use the microwave, we mostly cook outside on gas or a fire. I only use our air cond in really hot weather and I have a 240v external supply.

The good setups you will see on vans like Bushtracker, Kedron, where they may have 4+solar panels, 4+ batteries, a large inverter and quality wiring to support the intended function.

The inverter in my 4wd, its use is different, just for charging small items and running small items.

Go out and enjoy with what you have.. :o)
FollowupID: 817819

Follow Up By: Member - KBAD - Saturday, Jun 14, 2014 at 14:31

Saturday, Jun 14, 2014 at 14:31
Can i recommend Colynn Rivers books very helpful. The larger the appliance the more energy it will demand the shorter the capacity of the battery bank to supply it. For your Mac book finding a reliable 12 volt charger is next to impossible, two ways out for these get a modified wave inverter and charge your mac book up with that with the machine switched off, or get a pure sine wave inverter and run the commuter as you would normally that is operating it while charge is running in. I run a 300 watt modified wave inverter in the vehicle just to charge computers and cameras, and as i charge over things up at the same time in the van i have a larger 1000 watt pure sine wave inverter in there (but I am careful how long i run that one). If i want the air con or other large appliance then outcomes the generator.
Hope that helps
FollowupID: 817932

Sponsored Links