An apparatus, comprising: a drill string; and a downhole tool coupled to and conveyable with the drill string within a wellbore that extends into a subterranean formation, wherein the downhole tool comprises: an inlet in selective fluid communication with the wellbore or the subterranean formation; an inlet flow line fluidly coupled to the inlet; an outlet flow line fluidly coupled to an exterior of the downhole tool; a pumping system coupled between the inlet flow line and the outlet flow line; an energy accumulator; a turbine operable to receive a first fluid from the drill string and convert energy received via the first fluid into rotational energy; and a motor operable to: receive rotational energy from the turbine; convert at least a portion of the rotational energy received from the turbine into energy that is subsequently stored by the energy accumulator; receive and convert energy from the energy accumulator into rotational energy; and drive the pumping system to pump a second fluid from the inlet flow line to the outlet flow line by imparting, to the pumping system: rotational energy received from the turbine; and rotational energy converted from energy received from the energy accumulator. a drill string; and a downhole tool coupled to and conveyable with the drill string within a wellbore that extends into a subterranean formation, wherein the downhole tool comprises: an inlet in selective fluid communication with the wellbore or the subterranean formation; an inlet flow line fluidly coupled to the inlet; an outlet flow line fluidly coupled to an exterior of the downhole tool; a pumping system coupled between the inlet flow line and the outlet flow line; an energy accumulator; a turbine operable to receive a first fluid from the drill string and convert energy received via the first fluid into rotational energy; and a motor operable to: receive rotational energy from the turbine; convert at least a portion of the rotational energy received from the turbine into energy that is subsequently stored by the energy accumulator; receive and convert energy from the energy accumulator into rotational energy; and drive the pumping system to pump a second fluid from the inlet flow line to the outlet flow line by imparting, to the pumping system: rotational energy received from the turbine; and rotational energy converted from energy received from the energy accumulator. an inlet in selective fluid communication with the wellbore or the subterranean formation; an inlet flow line fluidly coupled to the inlet; an outlet flow line fluidly coupled to an exterior of the downhole tool; a pumping system coupled between the inlet flow line and the outlet flow line; an energy accumulator; a turbine operable to receive a first fluid from the drill string and convert energy received via the first fluid into rotational energy; and a motor operable to: receive rotational energy from the turbine; convert at least a portion of the rotational energy received from the turbine into energy that is subsequently stored by the energy accumulator; receive and convert energy from the energy accumulator into rotational energy; and drive the pumping system to pump a second fluid from the inlet flow line to the outlet flow line by imparting, to the pumping system: rotational energy received from the turbine; and rotational energy converted from energy received from the energy accumulator. receive rotational energy from the turbine; convert at least a portion of the rotational energy received from the turbine into energy that is subsequently stored by the energy accumulator; receive and convert energy from the energy accumulator into rotational energy; and drive the pumping system to pump a second fluid from the inlet flow line to the outlet flow line by imparting, to the pumping system: rotational energy received from the turbine; and rotational energy converted from energy received from the energy accumulator. rotational energy received from the turbine; and rotational energy converted from energy received from the energy accumulator.