A renewable energy device includes a wheel rotatably mounted on a base to spin about an axis of rotation and having a plurality of hollow, barbell-shaped fluid subassemblies fixed symmetrically about the axis. The fluid subassemblies each have a longitudinal axis radiating away from the axis of rotation, a hollow outer end defining a circular, ring-shaped, outer travel path when rotated about the axis of rotation, a hollow inner end defining a circular, ring-shaped, travel path disposed within the outer travel path when rotated about the axis of rotation, a hollow conduit fluidically connecting the outer and inner ends to define an interior cavity, and a room-temperature-boiling-point fluid disposed in the interior cavity. Inner and outer thermal variance subassemblies cover approximately half of respective ones of the inner and outer travel paths on at least one side of the wheel.