An imaging sensor, comprising: a pixel array comprising groups of pixels, each pixel (PV1, PV2, PV3, PV4) of the pixel array containing a photodiode (D1, D2, D3, D4), the photodiodes being isolated from one another by full thickness deep trench isolations; mode selection circuitry configured to control which groups of pixels of the pixel array operate in an imaging mode and which groups of pixels of the pixel array operate in an energy harvesting mode; and switch circuitry (105, 151) configured to selectively connect different groups of photodiodes in rows operating in the energy harvesting mode into forward biased series configurations between a voltage output line (VOUT) and a ground line, and/or into forward biased parallel configurations between the voltage output line and the ground line; wherein the mode selection circuitry comprises, for each first pixel of a given pixel group (100a1-100mn), an imaging selection transistor coupling an anode of the photodiode of that pixel to ground when in the imaging mode and an energy harvesting selection transistor coupling a cathode of the photodiode of that pixel to ground when in the energy harvesting mode; and wherein the mode selection circuitry comprises, for each pixel (PV2, PV3, PV4) of the given pixel group other than the first pixel of the given pixel group, an imaging selection transistor (MN19, MN21, MN23) coupling an anode of the photodiode of that pixel to ground when in the imaging mode and an energy harvesting selection transistor (MN5, MN9, MN13) coupling a cathode of the photodiode of that pixel to the switch circuitry for that pixel when in the energy harvesting mode; wherein the switch circuitry comprises, for each pixel (PV1, PV2, PV3) of the given pixel group (100a1-100mn) except a last pixel of the given pixel group: a transmission gate (160, 161, 162) selectively coupling the anode of the photodiode of that pixel to the energy harvesting selection transistor of a next pixel of the given pixel group; and a selection transistor (MN18, MN20, MN22) selectively coupling the energy harvesting selection transistor (MN5, MN9, MN13) of the next pixel of the given pixel group to ground when the transmission gate is not coupling the anode of the photodiode of that pixel to the energy harvesting selection transistor of the next pixel of the given pixel group. a pixel array comprising groups of pixels, each pixel (PV1, PV2, PV3, PV4) of the pixel array containing a photodiode (D1, D2, D3, D4), the photodiodes being isolated from one another by full thickness deep trench isolations; mode selection circuitry configured to control which groups of pixels of the pixel array operate in an imaging mode and which groups of pixels of the pixel array operate in an energy harvesting mode; and switch circuitry (105, 151) configured to selectively connect different groups of photodiodes in rows operating in the energy harvesting mode into forward biased series configurations between a voltage output line (VOUT) and a ground line, and/or into forward biased parallel configurations between the voltage output line and the ground line; wherein the mode selection circuitry comprises, for each first pixel of a given pixel group (100a1-100mn), an imaging selection transistor coupling an anode of the photodiode of that pixel to ground when in the imaging mode and an energy harvesting selection transistor coupling a cathode of the photodiode of that pixel to ground when in the energy harvesting mode; and wherein the mode selection circuitry comprises, for each pixel (PV2, PV3, PV4) of the given pixel group other than the first pixel of the given pixel group, an imaging selection transistor (MN19, MN21, MN23) coupling an anode of the photodiode of that pixel to ground when in the imaging mode and an energy harvesting selection transistor (MN5, MN9, MN13) coupling a cathode of the photodiode of that pixel to the switch circuitry for that pixel when in the energy harvesting mode; wherein the switch circuitry comprises, for each pixel (PV1, PV2, PV3) of the given pixel group (100a1-100mn) except a last pixel of the given pixel group: a transmission gate (160, 161, 162) selectively coupling the anode of the photodiode of that pixel to the energy harvesting selection transistor of a next pixel of the given pixel group; and a selection transistor (MN18, MN20, MN22) selectively coupling the energy harvesting selection transistor (MN5, MN9, MN13) of the next pixel of the given pixel group to ground when the transmission gate is not coupling the anode of the photodiode of that pixel to the energy harvesting selection transistor of the next pixel of the given pixel group. a transmission gate (160, 161, 162) selectively coupling the anode of the photodiode of that pixel to the energy harvesting selection transistor of a next pixel of the given pixel group; and a selection transistor (MN18, MN20, MN22) selectively coupling the energy harvesting selection transistor (MN5, MN9, MN13) of the next pixel of the given pixel group to ground when the transmission gate is not coupling the anode of the photodiode of that pixel to the energy harvesting selection transistor of the next pixel of the given pixel group.