The present disclosure relates to a method for storing excess energy from at least one energy producing source, as thermal energy, using an existing geologic formation. First and second storage zones formed in a geologic region may be used to store high temperature and medium high temperature brine. When excess energy is available from the energy producing source, a quantity of the medium high temperature brine is withdrawn and heated using the energy supplied by the energy source to form a first new quantity of high temperature brine, which is then injected back into the first storage zone. This forces a quantity of medium high temperature brine present in the first storage zone into the second storage zone, to maintain a desired quantity of high temperature brine in the first storage zone and a desired quantity of medium high temperature brine in the second storage zone.

A method for producing work is disclosed. The method includes increasing the pressure of a working fluid including carbon dioxide from a first pressure at least equal to a triple point pressure to a second pressure above the triple point pressure. The method also includes heating the working fluid, extracting mechanical work by expanding a first portion of the heated working fluid to a third pressure, supplying a second portion of the heated working fluid as a motive fluid to an ejector, increasing the pressure of the expanded working fluid by supplying the expanded working fluid to the ejector to combine with the motive fluid and form an output fluid at the fourth pressure, the fourth pressure at least equal to the triple point pressure of the working fluid. The method also includes refrigerating the output fluid to condense a vapor phase into a liquid phase.

A turbomachine (105) configured to compress supercritical carbon dioxide is shown. The turbomachine comprises, in fluid flow series, an inlet (201), an inducerless radial impeller (202) having a plurality of blades, and a fully vaneless diffuser (203). The radius of the inlet (r.sub.0) is from 25 to 50 percent of the radius of the impeller (r.sub.2).

This invention refers to an installation for the generation of mechanical energy using a Combined Power Cycle which comprises, at least; means to implement a closed or semi-closed regenerative constituent Brayton cycle which uses water as thermal fluid, means to implement at least one Rankine cycle, the constituent basic Rankine cycle, interconnected with the regenerative constituent Brayton cycle, and a heat pump (UAX) which makes up a closed circuit that regenerates the regenerative constituent Brayton cycle;
as well as the procedure for generating energy through the use of the cited installation.

The present disclosure relates to heat exchanger for a power generation system and related methods that use supercritical fluids, and in particular to a heat exchanger configured to minimize axial forces during operation.

The present invention provides a composition, such as a refrigerant composition comprising 1, 1-difluoroethene (vinylidene fluoride, R-1132a); trifluoromethane (R-23); and one or more compound selected from hexafluoroethane (R-116), ethane (R-170) and carbon dioxide (R-744, CO.sub.2).

The present disclosure relates to systems and methods for power production utilizing a recirculating working fluid. In particular, a portion of the recirculating working fluid can be separated from the main stream of recirculating working fluid as a bypass stream that can be compressed for adding heat to the system.

According to some embodiments, a supercritical waste heat recovery system comprises a first heat exchanger operable to introduce waste heat into a primary loop working fluid; a first turboexpander operable to expand the primary loop working fluid to produce electricity and/or mechanical work; a second heat exchanger operable to reject heat from the primary loop working fluid and introduce heat into a secondary loop working fluid; a third heat exchanger operable to reject additional heat from the primary loop working fluid; a first compressor operable to increase pressure of the primary loop working fluid; a second turboexpander operable to expand the secondary loop working fluid to produce electricity and/or mechanical work; a fourth heat exchanger operable to reject heat from the secondary loop working fluid; and a second compressor operable to increase pressure of the secondary loop working fluid.

A rotary liquid piston compressor and a power generation system including a first fluid loop. The first fluid loop includes a pump that circulates a liquid. A second fluid loop that generates power by circulating a supercritical fluid. The second fluid loop includes a turbine that rotates and powers a generator as the supercritical fluid flows through the turbine. A rotary liquid piston compressor fluidly coupled to the first fluid loop and the second fluid loop. The rotary liquid piston compressor exchanges pressure between the liquid circulating in the first fluid loop and the supercritical fluid circulating in the second fluid loop.

Gas turbine engines are described. The gas turbine engines include a compressor section, a combustor section, a turbine section, a nozzle section, wherein the compressor section, the combustor section, the turbine section, and the nozzle section define a core flow path that expels through the nozzle section, and a waste heat recovery system. The waste heat recovery system includes a heat recovery heat exchanger arranged at the nozzle section, wherein the heat recovery heat exchanger is arranged within the nozzle section such that the heat recovery heat exchanger occupies less than an entire area of an exhaust area of the nozzle section and a heat rejection heat exchanger arranged to reduce a temperature of a working fluid of the waste heat recovery system.