We present a novel photovoltaic cell architecture based on the electric field effect that controls carrier concentration in semiconductors using screening-engineered nanostructured electrodes. The device operates in inversion mode, with a top gate that forms a depletion layer and a p-n junction, and with nanostructured electrodes that collect the photocurrent across the junction. This architecture does not require any doping process or a heterojunction, opening an alternative path to fabricate cells on hard-to-dope materials such as oxides or phosphides. As a proof of concept, we present a field effect solar cell made of Si. To demonstrate the potential of this configuration for alternative materials, we also present a field-effect solar cell made of cuprous oxide, which has a favorable band gap but that is difficult to dope. We control the behavior of the devices with the gate voltage that forms an inversion layer and hence a rectifying p-n junction.