House batteries and free camping

suenami · Senior Member

House batteries and free camping

Xtrail51 · Senior Member

Hello. Maybe look into a bit of Solar. Great once you have it fitted.
Barb.

Gary and Kerry · Guru

You need to know exactly what you are going to use by wattage or amps.
For example, my TV is rated at 5 Amps, that means it uses 5 Amps per hour, most water pumps fitted to caravans/motorhomes are also 5 amps. Our average daily power consumption is 17 amps.
So look at everything you will using and work out your daily needs.

As Barb said have a look at solar.
We have 2 x 80W panels and 2 x 100Amp batteries fitted and the longest we have stayed out free is 18 nights and the only reason we have gone into a Cp is to have a long shower and do laundry.

Wombat 280 · Guru

I would check the computer if it's eating up the house battery in around 2 hours ,they drag bugger all amps. If everything else is on gas then it's only lights and maybe a radio so the total you have is about 80 amps (limiting it to a 50% discharge ) so you should get about a week + out of the battery bank without a recharge from the mains supply or solar panel

suenami · Senior Member

Sorry Wombat, I didn't say it right. I haven't free-camped yet. My laptop just lasts that long without plugging in.
Thanks Barb, Garry and Kerry. No-one explained much to me (they must have seen me coming hmm ). I discovered, in a cupboard above the bed, there's wiring, ready for solar.
What I'm asking is, can I plug in an ordinary 240v appliance to one of the powerpoints and use it? e.g. my toaster, elect frypan, or laptop etc. whilst on house batteries.
(Sorry to be so naive. Looking for websites that may explain it all)
cheers confuse

mike and Judy · Guru

--------------------------------------------------------------------------------
Hello Sue
no you cannot plug your 240 applainces into your batterey bank unless you have an inverter,to use them you should be in a CP,
with just two 80Amp hour betterey you would flatten them pretty quickly, the greatest users of power is heating and cooling, cooking and airconditiner,
I recommend you fit solar panels to the roof
I am surprised that you have got this far with out a loss of power allready

As with all electrical stuff the cooler it is the better it works, so make sure there is a gap underneath the solar panel for air flow when mounting them on the roof

I have four 80 watt panels to fit to the roof of the bus, and each panel puts out 5 amps when the sun is shining clear and uninterrupted on them, multiply amps by volts and you have 60 watts x2 panels, In general it will produce 70% of its rated power as it is not fixed to face north

For capacity, or amount of power on hand,, multiply both volts and amp hours to get the wattage, =12v X100 amp=1200 watts per hour battery,

So with your setup you have available 12v x 85amp x two =2040w

Dont take out more than 20% from the batteries, before charging them with a solar controller this is all automatic
if in a CP you can buy a 12v charger from any hardware place and plug it into the parks power supply which is 240volts, get one which will be rated above 7 amps
They have warning lights fitted and are really easy to use

If you have a TV which needs 75 watts, (you can see from the label on the back its power consumption, a radio that needs 10 watts, plus a speaker system as an extra that needs 30w, a computer that needs 30w, and a fridge that needs 60w then you add them all up for a total wattage of what you need and we have a total of them all =205 watts per hour

Howerver the sun doesnt always shine bright and clear, if a week went by with grey clouds,
you would be down a little on power
Another panel, or the use of a generator will be required,

Or you can reduce consumption,--------------- we are all different power users
you work it out from here.

if still in the dark let me know and I can turn on the light; at least try again

jandas fun · Guru

Hi Sue
not sure how much or what type of info you are after.
i have only free camped for the occasional night and use the 'in house battery' for lights only, as these are the only items hooked up to my 12v system.(apart from 3 way fridge which i have been told will flatten the battery quick smart).
If staying out longer you would need solar panels to recharge the in house battery or if you wish to have 240 v power you will need a generator. Think this simple answer is basically correct, the more knowledgeable will correct me no doubt.

If you turn off the power at the c/van park you are now in, you will see what is connected to your house battery.

Johnw

-- Edited by jandas fun on Friday 29th of May 2009 09:31:54 AM

Rolly · Guru

Collyn Rivers, a retired engineer I understand, has several books on matters RV including solar which are relatively easy reading.

His opinions are generally well respected on most RV fora.

http://www.caravanandmotorhomebooks.com/

suenami · Senior Member

Thanks everyone. Mike explained it pretty well. Like Jandas fun I'd only use lights. Rolly, I've read a bit from Collyn Rivers in the CMCA Mag and on their website. It's my ability to absorb and retain that is failing.
In all probability, and limited mobility, I'll stay with c/parks and rent assistance.Though I will venture out when I head north to outback Qld.

Have been stuck on Central Coast NSW waiting for water tank repairs - three weeks now - everyone is so busy and the traffic here terrifies me. Budgewoi is pretty on Lake Munmorah so no complaints - but give me 'the wide brown land' anytime..
Cheers,
Sue smile

Where To Next · Veteran Member

Dont take out more than 20% from the batteries, before charging them with a solar controller this is all automatic
if in a CP you can buy a 12v charger from any hardware place and plug it into the parks power supply which is 240volts, get one which will be rated above 7 amps

Hi Mike,

Can you further explain this paragraph for me ?

I am currently educating myself with the setup I am going to need in my transit van, and the rest of you reply above made sense to me, but I got lost with this paragraph.

I already have 240 volt setup in my van, I only have to get the input plug moved from the inside to the outside of the vehicle.

Getting my head around the house battery setup for free camping is quite the challenge. I am exploring all options with the goal of having the most simple setup possible to run a 60l Trailblazer as my freezer, a 38l Engel as my fridge, and a small microwave for maybe 20 minutes a day heating a meal or two. I am in the process of working out the number of house batteries I will need, whether an inverter is necessary, or whether I am better to run everything on 12 volt and only use mains power when at caravan parks (which would be only one or two days a week maximum).

Thank you,

Julie :)

-- Edited by Where To Next on Saturday 20th of April 2013 11:18:14 PM

-- Edited by Where To Next on Saturday 20th of April 2013 11:35:44 PM

beiffe · Guru

The percentage of usable power is calculated from the power rating stamped on the battery. eg with a 100AH battery you can use 20AH if you only have 20% to safely use.

There are different types of batteries so the 20% is for the cranking style wet cell batteries (the ones used in a car to start the engine) Not really the ones to have for house batteries.

If you have AGM's or GELS or similar then you can use about 50% of their rated power.

There are other batteries that give much greater power availability but are not widely used even though they are easier to use and give more power at a higher voltage for a longer time.

The rated available power is to stop the battery being depleted past a point where it can be safely bought back to 100% regularly. The more you take it past its rated available power level the shorter its life expectancy.

Most of the older style batteries should be returned to 100% withing 24 hours or there will be a loss of performance. In the RV lifestyle this is not possible so we accept a shorted life.

To get an AGM or similar battery to full takes days and many people assume that when the solar goes off boost it is full when it is really about 80 to 85% full. For a battery to be full there should be no charge being out in from the charging source.
If you in fact have deep cycle batteries you should be able to use about 50% so 40AH if your batteries are new and fully charged.

As batteries age their capacity drops and therefore the 50% value drops as well so you progressively get less available power. This is why you often hear people say "my batteries have been working well for 2 years or so but now seem to be failing" this is because the available power has been deceasing until the available power is not enough to deliver the AH's required. If you charge your batteries to 80% then you have 50% of that 80%. eg 80AH = full so 80% =64AH therefore you have 32AH available.

I hope this is the info you were seeking

Regards
Brian

Grams · Guru

Sue I am like you, this information got lost on me....somewhere on the first paragraph, I'm good with electronic things, but doing the battery, solar thing has lost me.

I am so lucky our van came with solar panels, in house batteries, even has 12V plugs inside and out. We are set up for free camping, but I don't think we will be using it for longer than 2-3 days at a time. Small town caravan parks and rent assistance sound good for the most part of our long term camping.

Good luck on getting your tank fixed, what a pain.

Pam · Guru

Suenami hasn't been on since 2009. Its amazing that these old threads surface isn't it.