A method for improving the efficiency of a Rankine cycle by reducing cold end loss, comprising: for a Rankine cycle with a reheat-cycle, reducing temperature of reheat steam or removing a reheat steam system, and for a Rankine cycle with regenerative steam extraction-heat, reducing temperature of main steam and increasing humidity of main steam.

To produce power using the cold in a stored fluid in a cold condensed state (for example, LNG or liquid air), the fluid is initially pumped, heated, and expanded to generate a first amount of power and form initially expanded fluid, which is then re-condensed, re-pumped, re-heated, and re-expanded to generate a second amount of power, where the initially expanded fluid is re-condensed against the pumped fluid from the initial pumping. The technique can be used to store excess energy in the cold condensed fluid using excess energy generation capacity for subsequent recovery when energy is either deficient or otherwise more expense to generate.

A waste heat recovery system for an engine system includes a first charge air cooler in communication with a working fluid path of the waste heat recovery system. The first charge air cooler includes a first waste heat recovery core and a first cooling fluid core. The first waste heat recovery core includes a first working fluid inlet configured to receive a working fluid from the working fluid path. The first working fluid conduit is coupled to the first working fluid inlet and a first working fluid outlet. The first cooling fluid core includes a first cooling fluid inlet in fluid communication with a cooling fluid source and a first cooling fluid conduit fluidly coupled to the first cooling fluid inlet and a first cooling fluid outlet. The first cooling fluid conduit is configured to direct cooling fluid from the first cooling fluid inlet to the first cooling fluid outlet.

Aspects of the present disclosure include a system for turbo-compression cooling. The system may be aboard a marine vessel. The system includes a power cycle and a cooling cycle. The power cycle includes a first working fluid, a waste heat boiler configured to evaporate the working fluid, a turbine, and a condenser. The condenser condenses the working fluid to a saturated or subcooled liquid. The cooling cycle includes a second working fluid, a first compressor configured to increase the pressure of the second working fluid, a condenser configured to condense the second working fluid to a saturated or subcooled liquid after exiting the first compressor, an expansion valve, and an evaporator. The turbine and first compressor are coupled one to the other. The waste heat boiler receives waste heat from engine jacket water and lubricating oil from a ship service generator. The evaporator cools water in a shipboard cooling loop.

An energy generation system for converting combustible fluid from a nontraditional combustible fluid source to useable energy. The energy generation system including a fluid storage system including a compressor and at least one storage tank, the compressor configured to pressurize a combustible fluid from a combustible fluid source for storage in the one or more storage tanks; and an energy recovery system configured to receive the combustible fluid from the at least one storage tank, the energy recovery system including: a turboexpander configured to depressurize the combustible fluid received from the at least one storage tank; a motor-generator configured to input the combustible fluid as depressurized by the turboexpander, and generate electrical energy from the combustible fluid; and an organic Rankine cycle (ORC) system configured to generate electrical energy based on a temperature differential between the combustible fluid input to the motor-generator and a waste heat produced by the motor-generator.

An integrated internal combustion engine and waste heat recovery system including an internal combustion engine, a system of exhaust gas conduits, a first heat exchanger in fluid communication with the exhaust gas conduits, a second heat exchanger in fluid communication with the exhaust gas conduits downstream of the first exchanger, a selective catalytic reduction unit positioned between the first and second heat exchangers, a waste heat recover system (WHR) and a mechanical connection. The WHR system includes a system of working fluid conduits in fluid communication with the first and second heat exchangers, an expander, a condenser, and a pump. The mechanical connection connects the internal combustion engine and the expander. The heat exchangers are configured to facilitate thermal communication between the working fluid and exhaust gas conduits. The working fluid and exhaust gas conduits include bypass conduits around the heat exchangers.

A combined heat and power system, or an energy system, is provided. A four-stroke opposed-piston engine provides efficient power from a generator set or genset. A heat exchange system is provided within the energy system to provide efficient waste heat recovery as the engine is operated.

Systems and methods are provided for the recovery mechanical power from heat energy sources using a common working fluid comprising, in some embodiments, an organic refrigerant flowing through multiple heat exchangers and expanders. The distribution of heat energy from the source may be portioned, distributed, and communicated to each of the heat exchangers so as to permit utilization of up to all available heat energy. In some embodiments, the system utilizes up to and including all of the available heat energy from the source. The expanders may be operatively coupled to one or more generators that convert the mechanical energy of the expansion process into electrical energy, or the mechanical energy may be communicated to other devices to perform work.

An optimized mechanical expander or fluid expansion device with a delayed opening timing is disclosed. In the optimized design, rotors in the expander alternatingly rotate sequentially through an intake position in which the transport volume is open to the housing inlet, a closed position in which the transport volume is closed to the housing outlet, and a discharge position in which the transport volume is open to the housing outlet. During rotation, a first opening forms between the housing and each rotor. After further rotation, a second opening is formed that is located between the first opening and a back end of the rotor. In one aspect, the mechanical expander has an opening profile including an initial opening phase in which the opening between the rotor and outlet forms at a lesser rate than during a subsequent secondary opening phase.

A system for warming an engine. The system includes an engine coolant system that directs warm engine coolant to the engine to heat the engine. A heat pump system warms the engine coolant.