Ah sorry, I didn't see that this was A level. The renal tubule (where the filtrate from the Bowman's capsule goes) is separated from the interstitial fluid of the kidney by a layer of cells, and there are different channels on each side. The side of the cell that's in contact with the tubule is called the tubular membrane, and the side of the cell that's in contact with the interstitial fluid is called the basolateral membrane. So channels on the basolateral membrane will move things from the cell into the interstitium and vice versa, which is effectively back into the bloodstream.
Technically, channels and ion pumps are different (channels are passive, pumps are active) so yes it just helps with facilitated diffusion.
I'm a first year medic with exams coming up soon and I'm currently revising the kidney which is where I got all this from, you won't need to know it for A level! But hopefully it'll help you understand it which is always helpful