The present disclosure relates to systems and methods useful for power production. In particular, a power production cycle utilizing CO.sub.2 as a working fluid may be combined with a second cycle wherein a compressed CO.sub.2 stream from the power production cycle, which can be heated and expanded to produce additional power and to provide additional heating to the power production cycle.

A method may include obtaining reservoir data for a geological region of interest. The method may further include obtaining turbine data regarding a supercritical carbon dioxide power (sCO2) turbine. The method may further include obtaining carbon emission data for a well coupled to the geological region of interest. The method may further include determining predicted production data and predicted carbon emission data using a machine-learning model, the reservoir data, the turbine data, and the carbon emission data. The method may further include transmitting a command to a control system based on the predicted production data and the predicted carbon emission data. The command may adjusts an amount of carbon dioxide that is distributed to an injection well and the sCO.sub.2 turbine. The command achieves a predetermined production rate at the well and a predetermined carbon footprint.

A thermodynamic system and method for performing work includes a working fluid and a fluid pump for pumping the working fluid through a cycle. A thermal input supplies heat to the working fluid. An expansion device downstream of the thermal input converts at least the heat of the working fluid to useful work. A heat exchanger downstream of the expansion device has a first portion to transfer heat from downstream said expansion device to a second portion at or upstream of said thermal input. A conversion device expands the working fluid with constant enthalpy from a higher to a lower pressure.

Systems and generating power in an organic Rankine cycle (ORC) operation to supply electrical power. In embodiments, an inlet temperature of a flow of gas from a source to an ORC unit may be determined. The source may connect to a main pipeline. The main pipeline may connect to a supply pipeline. The supply pipeline may connect to the ORC unit thereby to allow gas to flow from the source to the ORC unit. Heat from the flow of gas may cause the ORC unit to generate electrical power. The outlet temperature of the flow of the gas from the ORC unit to a return pipe may be determined. A bypass valve, positioned on a bypass pipeline connecting the supply pipeline to the return pipeline, may be adjusted to a position sufficient to maintain temperature of the flow of gas above a threshold based on the inlet and outlet temperature.

An apparatus includes first and second tanks each configured to receive and store a refrigerant under pressure. The apparatus also includes at least one generator configured to receive flows of the refrigerant between the tanks and to generate electrical power based on the flows of the refrigerant. The apparatus further includes first and second hydraulic drives associated with the first and second tanks, respectively. Each hydraulic drive includes a first piston within the associated tank, a channel fluidly coupled to the associated tank and configured to contain hydraulic fluid, and a second piston within the channel and configured to move within the channel in order to vary an amount of the hydraulic fluid within the associated tank and vary a position of the first piston within the associated tank. The channel of each hydraulic drive has a cross-sectional area that is less than a cross-sectional area of the associated tank.

The present invention provides methods and system for power generation using a high efficiency combustor in combination with a CO.sub.2 circulating fluid. The methods and systems advantageously can make use of a low pressure ratio power turbine and an economizer heat exchanger in specific embodiments. Additional low grade heat from an external source can be used to provide part of an amount of heat needed for heating the recycle CO.sub.2 circulating fluid. Fuel derived CO.sub.2 can be captured and delivered at pipeline pressure. Other impurities can be captured.

Apparatus, systems, and methods store energy by liquefying a gas such as air, for example, and then recover the energy by regasifying the liquid and combusting or otherwise reacting the gas with a fuel to drive a heat engine. The process of liquefying the gas may be powered with electric power from the grid, for example, and the heat engine may be used to generate electricity. Hence, in effect these apparatus, systems, and methods may provide for storing electric power from the grid and then subsequently delivering it back to the grid.

Apparatus, systems, and methods store energy by liquefying a gas such as air, for example, and then recover the energy by regasifying the liquid and combusting or otherwise reacting the gas with a fuel to drive a heat engine. The process of liquefying the gas may be powered with electric power from the grid, for example, and the heat engine may be used to generate electricity. Hence, in effect these apparatus, systems, and methods may provide for storing electric power from the grid and then subsequently delivering it back to the grid.

Lake Kivu contains ˜50 million tonnes (MT) dissolved biomethane. Efficient use is problematic from massive associated CO.sub.2: ˜600 MT. Conventional extraction scrubs CO.sub.2 with ˜50% overall CH.sub.4 loss, and returns ˜80% CO.sub.2 into the deep lake, preserving a catastrophe hazard threatening >2 M people. Methods and systems are disclosed coupling: (1) efficient CH.sub.4+CO.sub.2 degassing; (2) optional oxyfuel power generation and CO.sub.2 power cycle technologies; and (3) CO.sub.2 capture, processing, storage and use in a utilization hub. The invention optimally allows power production with >2× improved efficiency plus cryo-energy storage and large-scale greentech industrialization. CO.sub.2-utilizing products can include: Mg-cements/building materials, algal products/biofuels, urea, bioplastics and recycled materials, plus CO.sub.2 for greenhouse agriculture, CO.sub.2-EOR/CCS, off-grid cooling, fumigants, solvents, carbonation, packaging, ores-, biomass-, and agro-processing, cold pasteurization, frack and geothermal fluids, and inputs to produce methanol, DME, CO, syngas, formic acid, bicarbonate and other greentech chemicals, fuels, fertilizers and carbon products.

The present invention provides a method for open-loop controlling or closed-loop controlling and/or monitoring a device with an expansion engine which is supplied live steam of a working medium that is expanded to exhaust steam in the expansion engine comprising the steps: determining at least one physical parameter of the exhaust steam; determining at least one physical parameter of the live steam based on the determined at least one physical parameter of the exhaust steam; and open-loop controlling or closed-loop controlling and/or monitoring the device based on the at least one determined physical parameter of the live steam. A thermal power plant is also provided in which the method is realized.