dcdc charger? is it needed for 12v solar setup


New Member
hi, got myself a 2021 ranger has a canopy on the back and want to put the tub to good use for the few maybe 4 trips away every year
probably just runnng a fridge and a dual usb for charging phones / tablets

my query is is a dcdc charger important , would a 150w solar panel and a big agm do alright to keep the fridge ticking along or is the dcdc important just to arrive at camp with batterys at 100% ready for the fridge to be working with the lid being lifted frequently when the bevvies are on,

first time im building a setup. shes just a tourer spec van hauler



Well-Known Member
Use the search tab!

There are many threads on here to do with either dual battery systems or independent battery systems to run accessories.

How you do it is up to you.

I like dual battery because it gives you the ability to start your vehicle if your main starter fails & charge your AUX while your mobile.

But as mentioned there are many ways to set up a system to just run accessories like a fridge


Well-Known Member
Ctek do an awesome (but not cheap) dual battery setup with a DC-DC charger and MPPT solar controller built in.


Well-Known Member
To answer your question, the fridge (depending on size and whether used just as a fridge or as a fridge/freezer - both not specified) will draw 4 to 5 (or maybe more) amps per hour so your 150w solar panel will just keep up (maybe a fraction more) in good weather in the optimum position AND for only about 7-8 hours of sunlight. The rest of the time, the battery is discharging.
A good DCDC will pump in the recommended 10% of your AGM battery’s capacity every hour so a few hour’s drive between camps will replenish what your battery lost overnight.
Go to a lithium and your DCDC can pump in 33% of your battery’s capacity if your alternator and wiring are up to it.


Active Member
Do yourself a favour and build a setup with both alternator and solar inputs. Or at least plan for both when the pennies appear.

Eventually you'll face a situation where you're overnighting on the way to a more distant location or just experiencing garbage weather so solar doesn't do the trick. A week of intermittent rain in Tassie saw everyone in camp struggling and lots of vehicles idling to charge batteries.

I'm a big believer in dcdc and if you go lithium you'll need one.