Running fridge/freezer using solar

G'day,

We run a 60 lt trailblazer fridge and 2 fluro's on a 120 amp deep cycle battery and have a 128 watt solar panel with a regulator and worked well until it was cloudy for a few days in a row.
We now have it connected to the car so now the battery will be fully charged when we arrive at the camp site.

We have a 39 litre Autfridge that we use as a freezer. We have 2 by 70 watt panels supplying a second battery. This set-up keeps thingss going very well when it's sunny 90% of the day and the temperature doesn't get above about 30C.

The second battery is also wired up like yours through a Redarc isolator that switches the car's alternator output from the cranking battery to the fridge battery once the cranking batt is full.

On a recent trip from Perth to Darwin via The Plibara and The Kimberley, the freezer was OK until it got way up in the tropics, It then struggled a bit. Whilst it didn't defrost, it was working hard and we had to keep an eye on the battery charge state etc,,,

We even had to go for a drive once in a while to keep the second battery up to scratch.

When we git back in the southern half of WA, it all ran like clockwork and the 2 panels were well up to the job.

Bilbo

Hi Vicki

These things vary depending on where you are and how many average hours of sunlight you get per day.

In Melbourne its around 5hrs and as per above posts you need to have in excess of 100w of solar panels to go for a few days before battery needs a boost.

Robin Miller

Hi,
Set-up we used recently on the Canning Stock Route.

Nissan Patrol, dual battery(105Ah) 1 x 64 W UniSolar mounted flat on the roof rack , 1 x 80W Kyocera hinged and folding back from the other panel. Steca 15A Solar regulator. Running 1 x 40 Litre Engel as fridge, 1 x 21 Litre Engel as freezer, 12v Flojet pump.

Normal charging of the second battery while driving (Bi 80 regulator) and fold the 80W panel open while camped.

We were out for just over 2 weeks and spent a couple of days at a time camped. The set-up worked great with the battery maintaining charge and not dropping the load (via the solar reg) at any time.

I also use a Stecca Solar Regulator, and find them invaluable because of the available information is shown on a large LCD screen, so there is no guess work when placing a panel in the best position to get maximum Amps going to the battery.

My fridge/freezer runs at 8 Amps, (~2.8 AH)
I use ~200 Watt Solar system with 200+ AH AGM DC battery system.
Never have run out of power at any time, so I would suggest that's the maximum you will need.

Look at the Sharp Mono-crystalline 123 Watt panels specs as a starter.

Remember the numbers stated by manufacturers are the MAMIMUM numbers available on a perfect day, with perfect conditions, something that is not always available when camping, so a bit larger battery capacity is insurance.

Also some types of panels will start hours earlier to charge the battery than others.

The Solar regulator mentioned is the equivalent of a 3 stage battery charger in principal, not a on/off or basic regulator.

Maybe I would invest in a second battery if you are to be camping for long periods.