The present disclosure relates to an apparatus and associated methods for generating energy by capturing and taking benefit of the energy generated by any quantity of air surfacing inside water. The apparatus includes a frame structure to which is rotatably mounted an upper drive wheel, a lower wheel, and a vertical fluid column container. An endless chain of gas capsule elements is mounted on the upper and lower wheels. This endless chain passes vertically up into and through the fluid column container through a seal port in the bottom of the container. As the endless chain of gas capsule elements passes vertically through the fluid in the container, fluid pressure on the elements due to the height of the column of fluid in the container produces a net buoyant force upward on the elements, causing them to rise, generating kinetic energy that turns the wheels.