The invention provides a cogeneration system capable of adjusting a heat-to-electric power ratio not only in an increasing direction, but also in a decreasing direction. The cogeneration system includes: a power generation device configured to supply electric power; a first heat exchanger configured to exchange heat between exhaust of the power generation device and water, so as to lower a temperature of the exhaust and obtain steam from the water; a reformer configured to generate a reformed gas by the steam reacting with a fuel; a second heat exchanger configured to cool the reformed gas generated by the reformer by heat exchanging; a reformed gas supply device configured to supply the reformed gas cooled by the second heat exchanger to the power generation device; a distributor configured to supply the steam to at least one of the reformer and a heat utilization device; and a control device configure to adjust a heat-to-electric power ratio by changing a supply destination of the steam in the distributor.

Systems and methods are disclosed that can include operating a first rig component at a first location, capturing waste energy from the first rig component at the first location, and redirecting the waste energy to another rig component, another location, or a combination thereof. A method of operating a drilling rig can include operations of determining a power usage profile for a rig based on a digital rig plan; predicting waste energy to be generated during execution of the digital rig plan; and modifying the power usage profile for the rig and the digital rig plan based on the predicted waste energy.

Systems and methods are disclosed that can include operating a first rig component at a first location, capturing waste energy from the first rig component at the first location, and redirecting the waste energy to another rig component, another location, or a combination thereof. A method of operating a drilling rig can include operations of determining a power usage profile for a rig based on a digital rig plan; predicting waste energy to be generated during execution of the digital rig plan; and modifying the power usage profile for the rig and the digital rig plan based on the predicted waste energy.

The invention relates generally to methods and apparatus for integration of renewable and conventional energy to enhance electric reliability and reduce fuel consumption and emissions via thermal energy storage.

The invention relates generally to methods and apparatus for integration of renewable and conventional energy to enhance electric reliability and reduce fuel consumption and emissions via thermal energy storage.

Techniques for utilizing excess heat generated by an oven to generate electricity are provided. In one example, an oven can comprise a coolant pathway positioned adjacent to a hollow space within the oven, wherein the hollow space can contain heat. The oven can also comprise a chamber in fluid communication with the coolant pathway. The oven can further comprise a turbine in fluid communication with the chamber and an outlet. Moreover, the oven can comprise a generator connected to the turbine, wherein rotation of the turbine can power the generator.

Aircraft power plants including combustion engines, and associated methods for recuperating waste heat from such aircraft power plants are described. A method includes transferring the heat rejected by the internal combustion engine to supercritical CO.sub.2 (sCO.sub.2) used as a working fluid in a heat engine. The heat engine converts at least some the heat transferred to the sCO.sub.2 to mechanical energy to perform useful work onboard the aircraft.

Aircraft power plants including combustion engines, and associated methods for recuperating waste heat from such aircraft power plants are described. A method includes transferring the heat rejected by the internal combustion engine to supercritical CO.sub.2 (sCO.sub.2) used as a working fluid in a heat engine. The heat engine converts at least some the heat transferred to the sCO.sub.2 to mechanical energy to perform useful work onboard the aircraft.

A method for operating a heat recovery system for the utilization of waste heat of a heat engine of the heat recovery system may include discharging a carrier fluid via the heat engine, feeding the carrier fluid to an evaporator of a cyclic process of the heat recovery system, vaporizing a working fluid of the cyclic process via the evaporator and the waste heat, feeding the working fluid to an expansion engine of the cyclic process after vaporizing the working fluid, determining at least one carrier state variable of the carrier fluid at the evaporator, and setting at least one operating parameter of the heat recovery system based on the at least one determined carrier state variable.

A method for operating a heat recovery system for the utilization of waste heat of a heat engine of the heat recovery system may include discharging a carrier fluid via the heat engine, feeding the carrier fluid to an evaporator of a cyclic process of the heat recovery system, vaporizing a working fluid of the cyclic process via the evaporator and the waste heat, feeding the working fluid to an expansion engine of the cyclic process after vaporizing the working fluid, determining at least one carrier state variable of the carrier fluid at the evaporator, and setting at least one operating parameter of the heat recovery system based on the at least one determined carrier state variable.