A fuel cell includes a membrane electrode assembly (MEA), at least one separator plate disposed on a first side of the MEA, and at least one separator plate disposed on a second side of the MEA. The separator plate on the first side of the MEA may form a first group of channels for conducting a first reactant. The separator plate disposed on the second side of the MEA may form a second group of channels for conducting a second reactant. The first group of channels include a first set and a second set of channels alternatively positioned. Each of the first set of channels is positioned adjacent to a channel of the second set. Each of the two sets of channels includes an input controlled by an input valve and an output controlled by an output valve. The first group of channels forms an interdigitated flow field by closing the input valve of one of the two sets of channels and closing the output valve of the other of the two sets of channels, and forms a conventional flow field by opening both the input valve and the output valve.