No, because this kit is designed to charge a 12V battery. Technically, it’s possible to change solar panel connections to enable the kit to work in 24V mode; however, a qualified, knowledgeable individual should only do this.
Yes, it is recommended for better performance. Dust and dirt should first be swept off the panel surface using a soft brush. When the sweeping is complete, use a wet cloth to wipe the panel surface to remove remaining dirt and grime.
Renogy
Owner manual PDF of Renogy RNG-KIT-STCS100D-NC 100W Solar Panel Suitcase .