Abstract: This invention relates to a mechanical energy storage system, incorporating upper and lower reservoirs supported in a rigid frame. Metal balls are initially stored in the upper reservoir, a form of storage with potential energy that can be converted to kinetic energy. The balls are selectively released from the upper reservoir. The balls are then guided by a plurality of ramps, and said balls are then deposited in the lower reservoir. The invention further relates to renewable energy, such as solar energy, as a means of returning the balls from the lower to the upper reservoir. A further object is that the invention will continue to operate during those periods of time when solar energy is unavailable, without relying on backup power from battery packs or from power coming directly from a utility company.

Abstract: A portable conveyor system comprises an extensible and retractable boom assembly mounted on a transportable stationary support. The boom assembly comprises a plurality of longitudinally spaced rungs defining a series of supporting surfaces for a primary load carrier of the type described in applicant's co-pending U.S. patent application Ser. No. 75,410, now U.S. Pat. No. 4,793,437. The improvements described herein include a vertically adjustable hitch mounted forwardly on a frame of the primary load carrier. The hitch is adapted for attachment to the end of the cable of a winch assembly to move the endless tracks of the carrier in full contact along the supporting surfaces of the rungs. Other improvements include modified boom and overhead bracket assemblies, a resilient suspension system for the primary load carrier and a platform assembly attachable to either end of the boom assembly to alternately function as a loading or unloading platform.