Help! I have two brand new 30a 12 v. solar panels; mono crystali

[Humberto]

Help! I have two brand new 30a 12 v. solar panels; mono crystaline each with a 20 v. output at high noon. I want to power a 12 v. 1.8 a air pump and an 18 w. 12 v. water pump. So I used an adjustable buck converter to step down the DC current to 12 v. and my pump does not even budge. I replaced the buck with a three prong 12 v. voltage converter, still no movement. However this might shine some light on the problem. I used first a 22v. battery to calibrate the buck, and it lit up as I adjusted the set screw to achieve 12 v. When I did the same test using my solar panels, there was no light on or current equal to 12 v. coming from the buck converter. I' m using solar cables and connectors. What did I miss?.

 

[Skalabala]

Solar panels needs a battery bank for buffering. They are not good for direct load.
Just get a solar charge controller and four 7.2ah 12v batteries and you will be good.
These items are not expensive at all.

 

[Humberto]

Thanks, I already bought a 35 am hr deep cycle battery.

 

[Humberto]

Can a 48 v. Bike battery be trickle charged with a 100 w. 18v. Solar panel, and does that also require a step up transformer or voltage regulator?. I found a flexible solar panel on sale, that could be fashioned into a back or front wheel cover. I won't buy it until I get the OK to proceed with a parts list. Thanks for your input.

 

[veloman]

Can a 48 v. Bike battery be trickle charged with a 100 w. 18v. Solar panel, and does that also require a step up transformer or voltage regulator?. I found a flexible solar panel on sale, that could be fashioned into a back or front wheel cover. I won't buy it until I get the OK to proceed with a parts list. Thanks for your input.

Yes that will work, with a step up convertor. That's how I use one of my panels - 17v DC open circuit - 58.5v DC output via convertor. The closer the two voltages, the better efficiency, in general.