Abstract: The present invention is directed to a control strategy for operating a plurality of prime power sources during propulsion, idling and braking and is applicable to large systems such as trucks, ships, cranes and locomotives utilizing diesel engines, gas turbine engines, other types of internal combustion engines, fuel cells or combinations of these that require substantial power and low emissions utilizing multiple power plant combinations. The present invention is directed at a general control strategy for multi power plant systems where the power systems need not be of the same type or power rating and may even use different fuels. The invention is based on a common DC bus electrical architecture so that prime power sources need not be synchronized.

Abstract: An electric generator system for producing electric power from the environmental temperature changes such as occur during a normal summer day on Earth or Mars. In a preferred embodiment a phase-change mass is provided which partially or completely freezes during the relatively cold part of a cycle and partially or completely melts during the relatively hot part of the cycle. A thermoelectric module is positioned between the phase-change mass and the environment. The temperature of the phase-change mass remains relatively constant throughout the cycle. During the hot part of the cycle heat flows from the environment through the thermoelectric module into the phase change mass generating electric power which is stored in an electric power storage device such as a capacitor or battery. During the cold part of the cycle heat flows from the phase change mass back through the module and out to the environment also generating electric power that also is similarly stored.