A turbine for solar thermal power generation and a Brayton cycle are disclosed. The turbine includes a blade which has a cooling working medium inlet and a cooling working medium jet orifice. The blade is provided as a cavity with hollow interior; the cooling working medium inlet is located inside the blade; the cooling working medium jet orifice is provided on the blade surface on which is provided a spectral conversion coating; the spectral conversion coating converts heat on the blade surface into conversion characteristic band radiation which is radiation energy adjacent to cooling working medium characteristic band radiation of a cooling working medium. The turbine adopts a characteristic spectral coating and a jet cooling to enhance the cooling effect for a turbine blade and to improve the system efficiency of the Brayton cycle.

According to the present invention, part of carbon dioxide heated by a heater is supplied to a dry gas seal portion of a compressor so that a device for pressurizing and heating a seal gas is not additionally required, configuration can be simplified and cost can be reduced. In addition, a seal gas flow path includes a low-temperature seal gas flow path and a high-temperature seal gas flow path so that, in an initial driving mode, carbon dioxide heated by a high-temperature portion of the heater is used as a seal gas and in a turbine-driving mode, carbon dioxide heated by a low-temperature portion of the heater is used as a seal gas and thus a more efficient operation can be performed.

A geo-energy production system and method extracts thermal energy from a reservoir formation, and stores either thermal waste heat or excess heat in a storage zone of the reservoir formation. A compressed fluid injection injects an unheated, compressed working fluid into the storage zone. A fluid injection well injects a working fluid laden with thermal waste heat or excess heat into the storage zone. The storage zone is located below a caprock layer and above a native brine zone of the reservoir formation and is partially circumscribed by a hot brine storage zone. The compressed working fluid assists with a withdrawal of pressurized brine residing below and/or to the sides of the storage zone. A compressed CO.sub.2, N.sub.2, or air production well helps to remove compressed working fluid from the storage zone for use in power production.

Systems and methods are provided to cool a heat producing component in an electrical machine system. The electrical machine includes a supercritical carbon dioxide (SCO.sub.2) wherein the SCO.sub.2 is a working medium of a heat exchanger that is arranged in the electrical machine system to cool a fluid that cools the heat producing component and/or wherein the SCO.sub.2 directly cools at the heat producing component.

A near-adiabatic engine has four stages in a cycle: a means of near adiabatically expanding the working fluid during the downstroke (expansion stroke); a means of cooling the working fluid at Bottom Dead Center (BDC); a means of near adiabatically compressing that cooled fluid from the lower pressure/temperature level at BDC to the higher level at Top Dead Center (TDC); and finally, a means of passing that working fluid back into the high pressure/temperature source in a balanced condition with minimal resistance to that flow.

A combined power generation system performing pressure difference power generation includes a pressure difference power generation facility generating electricity by using a pressure change of natural gas; a gas turbine power generation facility including a compressor, a combustor, a turbine, and a generator; and a heating unit to heat the natural gas discharged from the pressure difference power generation facility. A first bypass channel enables the natural gas to bypass the pressure difference power generation facility, and a second bypass channel enables the natural gas to bypass the heating unit. The heated natural gas is heated to a high temperature and then introduced into the combustor of the gas turbine power generation facility. Since the natural gas to be used in the gas turbine power generation facility is preliminarily heated while passing through the preceding power generation facility, the generation efficiency of the gas turbine power generation efficiency is improved.

Heat engines employing fluid bearing assemblies hermetically sealed with a closed flowpath for a working fluid are generally disclosed. For example, the heat engine includes a rotating drivetrain and a fluid bearing assembly. The rotating drivetrain includes a compressor section, an expander section, and a heat exchanger. The compressor section and expander section together define at least in part a closed flowpath for the flow of a working fluid. The heat exchanger is thermally coupled to the closed flowpath for adding heat to the working fluid. The fluid bearing assembly is configured to utilize the working fluid to support the rotating drivetrain. Further, the fluid bearing assembly is hermetically sealed with the closed flowpath.

The present invention relates to systems and methods for controlling a power production plant and optionally providing a one or more product streams for an end use thereof. Control of a power production plant specifically can include executing one or more functions effective for adjusting a heat profile of a heat exchange unit (HEU) operating with a plurality of streams passing therethrough. This can include implementing a control function that alters a flow of one or more of the plurality of streams by adding flow to or withdrawing flow one or more of the plurality of streams at an intermediate temperature range within the HEU at a point that is positioned between a first end and a second end of the HEU.

A system method of geothermal energy recovery includes injecting carbon dioxide into a geothermal reservoir through an injection well, extracting a working fluid including previously injected carbon dioxide and hydrocarbons entrained in a flow of the carbon dioxide within the reservoir from an extraction well, separating components of the heated working fluid based on chemical composition, selectively mixing the separated components according to the current conditions of the extracted working fluid to produce an output modified working fluid that having a chemical composition that is optimized for energy recovery efficiency, and expanding the modified working fluid to generate mechanical or electrical energy.

In some embodiments the disclosure is directed to a closed-loop piston engine system using a recirculating carbon dioxide (CO.sub.2) system with supercritical carbon dioxide (scCO.sub.2) as a working fluid. The closed-loop piston engine system may include a scCO.sub.2 injector; a superheating nozzle region; a first valve; a second valve; a piston moving in the cylinder and coupled with a crankshaft, the piston being driven toward a centerline of the crankshaft during a power stroke using a connecting rod and causing the crankshaft to rotate thereby causing one power stroke per crankshaft rotation and thereby producing two power strokes for every single power stroke that a similar engine would produce if run as a hydrocarbon fuel powered internal combustion engine. The recirculating CO.sub.2 system recirculates the used carbon dioxide and there are no carbon dioxide emissions from the system.