Aspects of the invention provided herein include heat engine systems, methods for generating electricity, and methods for starting a turbo pump. In some configurations, the heat engine system contains a start pump and a turbo pump disposed in series along a working fluid circuit and configured to circulate a working fluid within the working fluid circuit. The start pump may have a pump portion coupled to a motor-driven portion and the turbo pump may have a pump portion coupled to a drive turbine. In one configuration, the pump portion of the start pump is fluidly coupled to the working fluid circuit downstream of and in series with the pump portion of the turbo pump. In another configuration, the pump portion of the start pump is fluidly coupled to the working fluid circuit upstream of and in series with the pump portion of the turbo pump.

A dispatchable storage combined cycle power plant comprises a topping cycle that combusts fuel to generate electricity and produce hot exhaust gases, a steam power system, a heat source other than the topping cycle, and a thermal energy storage system. Heat from the heat source, from the thermal energy storage system, or from the heat source and the thermal energy storage system is used to generate steam in the steam power system. Heat from the topping cycle may be used in series with or in parallel with the thermal energy storage system and/or the heat source to generate the steam, and additionally to super heat the steam.

The present invention relates to a system for eliminating the presence of droplets in a first medium of a heat exchanger. The heat exchanger has an inlet port and an outlet port for the first medium as well as an inlet port and an outlet port for a second medium. The system comprises (a) a device for regulating the flow of the first medium into the heat exchanger, (b) a first temperature sensor array for measuring the temperature of the first medium exiting the heat exchanger, and (c) a controller for regulating flow of the first medium into the heat exchanger. The system further comprises a second temperature sensor array for measuring the temperature of the second medium entering the heat exchanger. The controller regulates the flow of the first medium into the heat exchanger based on data received from the first temperature sensor array and second temperature sensor array.

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.

An energy storage plant includes a casing for the storage of a working fluid other than atmospheric air, in a gaseous phase and in equilibrium of pressure with the atmosphere; a tank for the storage of said working fluid in a liquid or supercritical phase with a temperature close to the critical temperature; wherein said critical temperature is close to the ambient temperature. The plant is configured to carry out a closed thermodynamic cyclic transformation, first in one direction in a charge configuration and then in the opposite direction in a discharge configuration, between said casing and said tank; wherein in the charge configuration the plant stores heat and pressure and in the discharge configuration generates energy.

A duct intersection comprising a first duct portion and a second duct portion extending laterally from a side of the first duct portion. At least one flow modifier is mounted inside one of the first and second duct portions. The flow modifier is a contoured duct liner and/or the flow modifier includes at least one turning vane. The duct intersection may also include a transition portion extending between the first and second duct portions, wherein the transition portion has a length extending along a side of the first duct portion and a depth extending away from the side of the first duct portion, wherein the length is greater than a diameter of the second duct portion.

Systems and processes provide for a thermal process to transform sludge (and a variety of other natural waste materials) into electricity. Dewatered sludge and other materials containing a high amount of latent energy are dried into a powdered biofuel using a drying gas produced in the system. The drying gas is recirculated and is heated by the biofuel produced in the system, waste heat (from turbines or internal combustion engines), gas (including natural gas or digester gas) and/or oil. The biofuel is combusted in a boiler system that utilizes a burner operable to burn biofuel and produce heat utilized in a series of heat exchangers that heat the recirculating drying air and steam that powers the turbines for electricity production.

The present disclosure provides pumped thermal energy storage systems that can be used to store electrical energy. A pumped thermal energy storage system of the present disclosure can store energy by operating as a heat pump or refrigerator, whereby network input can be used to transfer heat from the cold side to the hot side. A working fluid of the system is capable of efficient heat exchange with heat storage fluids on a hot side of the system and on a cold side of the system. The system can extract energy by operating as a heat engine transferring heat from the hot side to the cold side, which can result in network output. Systems of the present disclosure can employ solar heating for improved storage efficiency.

An energy storage plant includes a casing for the storage of a working fluid other than atmospheric air, in a gaseous phase and in equilibrium of pressure with the atmosphere; a tank for the storage of said working fluid in a liquid or supercritical phase with a temperature close to the critical temperature; wherein said critical temperature is close to the ambient temperature. The plant is configured to carry out a closed thermodynamic cyclic transformation, first in one direction in a charge configuration and then in the opposite direction in a discharge configuration, between said casing and said tank; wherein in the charge configuration the plant stores heat and pressure and in the discharge configuration generates energy.

Systems and processes provide for a thermal process to transform sludge (and a variety of other natural waste materials) into electricity. Dewatered sludge and other materials containing a high amount of latent energy are dried into a powdered biofuel using a drying gas produced in the system. The drying gas is recirculated and is heated by the biofuel produced in the system, waste heat (from turbines or internal combustion engines), gas (including natural gas or digester gas) and/or oil. The biofuel is combusted in a boiler system that utilizes a burner operable to burn biofuel and produce heat utilized in a series of heat exchangers that heat the recirculating drying air and steam that powers the turbines for electricity production.