A thermodynamic apparatus, such as a Stirling engine or a Vuilleumier heat pump, has a heat exchanger in which energy is exchanged between a working fluid and an exhaust gas stream. On top of the cylinder of the thermodynamic apparatus is a dome-shaped section. By incorporating the heat exchanger within the dome, the flow paths can be simplified, the number of separate components reduced, and overall weight reduced. Flow passages for the working fluid are embedded in the dome. Channels for the exhaust gases are formed in an outer surface. The passages and the channels are helically arranged, one clockwise and one counter clockwise. The dome can be cast with a core for the casting fabricated via three-dimensional printing. In some embodiments, the dome is made of fiber-reinforced material.

A system is described which includes a Brayton cycle engine having a compressor, a turbine, a hollow rotating shaft that extends between a first end and a second end, a hollow tubing that interconnects the first end and the second end, and a heat source; a thermoacoustic Stirling cycle engine disposed within the hollow rotating shaft between the first and second ends thereof, the Stirling cycle engine including a cold side heat exchanger disposed adjacent to the compressor, a hot side heat exchanger disposed adjacent to the turbine, and a regenerator disposed between the cold and hot side heat exchangers; a first power generator disposed within the hollow tubing and located adjacent to the second end of the hollow rotating shaft; and, a second power generator disposed around the hollow rotating shaft between the first and second ends. The system can be arranged in a quad configuration having four stages.

A system for energy conversion, the system including a closed cycle engine containing a volume of working fluid, the engine comprising a first chamber defining an expansion chamber and a second chamber defining a compression chamber each separated by a piston attached to a connection member of a piston assembly, and wherein the engine comprises a heater body in thermal communication with the first chamber, and further wherein the engine comprises a cold side heat exchanger in thermal communication with the second chamber, and wherein a third chamber is defined within the piston, wherein the third chamber is in selective flow communication with the first chamber, the second chamber, or both.

In a Stirling refrigerator, a displacer has an internal space. An expander body houses the displacer so that the displacer can be reciprocated. A temperature sensor is arranged in the internal space of the displacer. A displacer rod, having an internal space, may connect to the displacer. A wiring may provide an electrical connection to the temperature sensor, the wiring arranged through the internal space of the displacer rod to outside of the expander body.

Heat from a safe high energy density fuel, such as aluminum, is used to generate electrical power. In some applications, the fuel may use seawater as an oxidizer. Additionally, the hybrid power system uses a highly efficient and silent thermoacoustic power converter (TAPC) to convert the thermal energy from the oxidation of aluminum to AC electrical energy. The AC electrical energy is converted to DC energy and stored in a battery. In situations demanding low power, the battery can provide power while the fuel combustion process is suspended.

A system for distributed utilities including electrical power and water. A generation device is provided for converting an available resource to a desired utility; the resource may be water, in which case the generator is a purifier for purifying untreated water, or, alternatively, the generator may convert a fuel to electrical power. In either case, an input sensor is provided for measuring input to the generation device, while an output sensor is provided for measuring consumption of output from the generation device. The monitoring system has a controller for concatenating measured input and consumption of output on the basis of the input and output sensors. Measured parameters are telemetered to a remote site where utility generation and use are monitored and may also be controlled. At least a portion of the electrical power capacity of the electric generation unit may power a water purification unit such as a vapor compression distillation unit, and heat output of the electric generation unit may supply heat to the water purification unit.

A Stirling engine includes: the thermosiphon that accommodates the heating medium receiving heat from a heat source; and an engine unit that has a body accommodating working gas. A heater that gives heat to the working gas by the heating medium is arranged in the body. The Stirling engine includes an engine controller that executes control for increasing an absorbed amount of thermal energy from the heating medium when at least one of the pressure and the temperature of the heating medium exceeds a predetermined value.

A thermoacoustic transducer includes a mechanical converter providing power conversion between acoustic and mechanical power and includes a diaphragm defining a compression and an expansion chamber. A thermal converter including a flow passage having a regenerator portion is thermally coupled for conversion between acoustic and thermal power. The mechanical converter is in fluid communication with the flow passage through transmission ducts completing an acoustic power loop having a volume containing a working gas. A transmission duct cross-sectional area is less than a regenerator flow area, which is less than a diaphragm surface area. The diaphragm undergoes resilient displacement causing pressure oscillations within the volume. The power loop is configured to cause one location along the loop to have anti-phase pressure oscillations to pressure oscillations in the mechanical converter.

Disclosed is an energy collector system applicable to internal combustion engines. It may include: a) a collector of thermal energy from the exhaust gases; b) a thermal tank covered by helical tubes to gain heat by the exhaust gases; c) a heat exchanger; and d) an outer element capable of converting thermal energy into mechanical energy, such as a closed Brayton cycle turbine, a Stirling engine, a Rankine turbine or an open loop air motor for converting mechanical energy (coupling the difference in rpm) into electrical energy with an electrical generator. The thermal energy collector may be composed of a heat exchanger that collects energy from the exhaust gases. The electrical energy generated may be used for driving a hybrid vehicle. The thermal tank is capable of storing energy as heat, as well.

The present invention provides a heat medium circulation structure for a micro-combined heat and power (micro-CHP) generator in which a heat medium that primarily looses heat by undergoing heat exchange with water in a hot-water tank and thus has a low temperature further performs heat exchange with low-temperature direct water supplied through a direct water line, thereby further loosing heat, in a return line heat exchanger, and then returns to a stirling engine through a heat medium return line, thereby effectively cooling a low temperature portion of the stirling engine. Thus, the heat medium circulation structure enables high electricity production efficiency. Further provided is a hot water temperature control method for a micro-CHP generator in which the consumption of hot water is detected by a flow sensor. First and second predetermined temperatures are defined to operate a stirling engine in the case of temperature droppings of hot water respectively due to natural radiation and consumption of hot water.