Solvent deasphalting apparatus includes a separator that receives two inputs, a heavy hydrocarbon feed and a solvent feed; and the apparatus produces two outputs, an asphaltene/solvent stream and a deasphalted oil/solvent stream. A solvent recovery unit of the apparatus receives the two output streams and produces mainly a substantially solvent-free deasphalted oil product stream, a substantially solvent-free asphaltene product stream, and a recovered solvent stream which is returned to a solvent drum. A pump pumps a substantially constant volume of solvent from the solvent drum into a by-pass line connecting the pump to the solvent drum, and into a connection line connecting the pump to the separator. The amount of solvent flow in the connection line is functionally related to the level of heavy hydrocarbon feed so that solvent in excess of that flowing into the connection line and spills back to the solvent drum through the by-pass line. Finally, a power generator generates power in response to the flow of solvent in the by-pass line. The power generator includes a vaporizer for vaporizing solvent in the by-pass line, an organic vapor turbine responsive to vaporized solvent for expanding the vaporized solvent and producing expanded vaporized solvent, and generating power, a condenser for condensing the expanded vaporized solvent and producing condensed solvent, and a pump for returning the condensed solvent to the drum.