Need advice regarding a small solar/ battery offgrid system setup

cubix

Looking to create a basic setup to charge up some walk talkie radios which are left on a site with no power. Is there simple reasonable cost solution that would allow me put up a panel and necessary bits to allow these be trickle charged

graememk

https://www.boards.ie/discussion/2058355743/need-advice-regarding-a-small-solar-battery-offgrid-system-setup

Solar panel, charge controller, 12 v deep cycle battery

cubix

Thanks, will this setup allow me to plug in a standard three pin plug for the radio base station. If so any particular charge controller/ 12v battery recommendations

10-10-20

https://www.boards.ie/discussion/comment/122254091#Comment_122254091

No, you'd need a full off-grid inverter and battery pack for that. Ideally look for a 12v/24v charger for the radios instead of going down the 230v AC inverter route.

10-10-20

Here's an Irish supplier:

https://mpe-online.ie/product-category/pv-solar/

Have a look at the solar charge controllers and try size it off that.

cubix

Any links to a suitable inverter/ battery pack that might suit the purposes

10-10-20

https://www.boards.ie/discussion/comment/122254122#Comment_122254122

See link above and also look at this simple controller.

https://mpe-online.ie/shop/pv-solar/pv-solar-charge-controllers/bluesolar-lcd-pwm/

cubix

Thanks,

If I choose not to connect a battery could I have just have a solar panel/ charger controller and connect the radios to this with the understanding the radios only charging when there is daylight enough to trigger a charge

Or do I need a solar panel/ battery/ charge controller and then radio

If I do need a battery would I get away with cheap 8 AMp hours type or would I have to go up to something like a 38AH

10-10-20

https://www.boards.ie/discussion/comment/122254202#Comment_122254202

Nobody does it like that, a battery is always used to store charge, otherwise you'll have very unpredictable results. You would need to size the battery based on the expected load - have a look on here as I have posted about sizing before and it will contain a link to a sizer tool.

Usually it goes: solar panels (18-24v) into solar charge controller into 12v battery, then into device charger and out to device.

The device charger could be a good quality 12v to USB charger device or something like this:

https://gleanntronics.ie/en/products/3a-6-24v-dc-usb-charger-step-down-dc-dc-buck-converter-164.html?query_id=1

cubix

No worries, will check it out. Thanks

graememk

We have one of these for pumping water,

https://solarpumpsolutions.ie/solarflo-35/

Its a 12V deep cycle lead acid battery, Pump, 12v panel, charge controller.

So for charging your radios, Do you have a site hut of some sort?

You possibly wont even need the deep cycle battery as the radios are likely to need very little, Id even try it with a normal 12v if you have one lying around.

If you can get a "car" eg a 12 v charger for the radios, you just connect that to the load output of the charge controller.

The charge controller will stop over discharge of the battery, but likely any panel you get will be more than enough to keep the radios charged.