Solar panel question

Wizard

Hi guys.
Thinking of adding solar to my camper. I would ideally like to charge 2 x 110 leisure batteries and also keep the vehicle battery topped up.
What size panel would I need and would a dual battery controller do if I had the leisure batteries connected ?
Thanks a mil in advance guys.

Wizard

Wizard wrote: »

What size panel would I need

Impossible to say without knowing the power demand requirements and the window of opportunity for charging.
If I was to throw arbitrary figures about I'd say.
50Wp for a battery maintainer.
100Wp - 150Wp for a touring supply with power on demand capabilities.
300Wp + for a touring supply with an electric fridge onboard.

Obviously system parasitic loads, expected appliance loads, appliance efficiency, climate at time of use, average depth of discharge, age and condition of battery, installation losses, etc.. Are factors to be considered.

If you want power on demand on the fringes of Spring and Autumn then tilting mounts are a must.

Wizard wrote: »

and would a dual battery controller do if I had the leisure batteries connected ?

Two connected batteries = one battery. So if the intention is to just charge the habitation battery then a normal solar controller is required.
There's nothing special about dual battery controllers, they're just dual shottky protected outputs, with a regulation point compensating for the diode losses.
If you want to split charge the engine battery I'd use a low quiescent voltage sensing relay based split charger.

I don't know any dual battery chargers that are suitable for flooded batteries. The highest I've seen has a 14.4v max regulation threshold.

Wizard

Sir Liamalot wrote: »

Impossible to say without knowing the power demand requirements and the window of opportunity for charging.
If I was to throw arbitrary figures about I'd say.
50Wp for a battery maintainer.
100Wp - 150Wp for a touring supply with power on demand capabilities.
300Wp + for a touring supply with and electric fridge onboard.

Obviously system parasitic loads, expected appliance loads, appliance efficiency, climate at time of use, average depth of discharge, age and condition of battery, installation losses, etc.. Are factors to be considered.

If you want power on demand on the fringes of Spring and Autumn then tilting mounts are a must.




Two connected batteries = one battery. So if the intention is to just charge the habitation battery then a normal solar controller is required.
There's nothing special about dual battery controllers, they're just dual shottky protected outputs, with a regulation point compensating for the diode losses.
If you want to split charge the engine battery I'd use a low quiescent voltage sensing relay based split charger.

I don't know any dual battery chargers that are suitable for flooded batteries. The highest I've seen has a 14.4v max regulation threshold.

Thanks a million for your reply. I was looking at a 100w kit that included a dual battery regulator. I was hoping to connect it up with 1 output to 2 110ah batteries and the other to the vehicle battery.
Don't plan on living off grid but was hoping to have the option of several days without hookup .
Have fridge and TV and lights. Nothing else to power .

crabbypaddy

Wizard wrote: »

Thanks a million for your reply. I was looking at a 100w kit that included a dual battery regulator. I was hoping to connect it up with 1 output to 2 110ah batteries and the other to the vehicle battery.
Don't plan on living off grid but was hoping to have the option of several days without hookup .
Have fridge and TV and lights. Nothing else to power .

Is the fridge on gas?
Are the lights led, flourescent or halogen - check how many watts total.
Any heating?
How many watts is the tv, is it running direct from the 12v or via an inverter, is it hooked up to a satellite box - check how many watts if so.