A compressed-air energy storage system according to embodiments of the present invention comprises a reversible mechanism to compress and expand air, one or more compressed air storage tanks, a control system, one or more heat exchangers, and, in certain embodiments of the invention, a motor-generator. The reversible air compressor-expander uses mechanical power to compress air (when it is acting as a compressor) and converts the energy stored in compressed air to mechanical power (when it is acting as an expander). In certain embodiments, the compressor-expander comprises one or more stages, each stage consisting of pressure vessel (the “pressure cell”) partially filled with water or other liquid. In some embodiments, the pressure vessel communicates with one or more cylinder devices to exchange air and liquid with the cylinder chamber(s) thereof. Suitable valving allows air to enter and leave the pressure cell and cylinder device, if present, under electronic control.

Compressed air energy storage system utilizing two-phase flow to facilitate heat exchange

An improved power plant employing a combination of compressed air storage and saturation (simultaneous heating and humidification) of compressed air is disclosed. The power plant (20A) includes a combustor (26) which provides hot gas for driving a turbine (24). The turbine (24) is used in conjunction with a generator (34) to generate electrical power. The power from the turbine (24) is accessible by a compressor system (40) during low power demand periods. The compressor system (40) is used to compress air which is stored in an air storage chamber (52). The compressed air from the air storage chamber (52) is used by the combustor (26) during high power demand periods, while the compressor system (40) is shut down, to provide compressed combustion gas to the turbine (24). To enhance the efficiency of the plant, while further lowering the capital cost of the plant, a saturator (60) is positioned between the storage chamber (52) and the combustor (26). The saturator (60) receives compressed air from the storage chamber (52) and simultaneously heats and humidifies it. The resultant heated and humidified compressed air is then conveyed to the combustor (26), typically after further heating by a recuperator (70).

Power plant utilizing compressed air energy storage and saturation.

The cumulative global capacity of organic Rankine cycle (ORC) power systems for the conversion of renewable and waste thermal energy is undergoing a rapid growth and is estimated to be approx. 2000 MWe considering only installations that went into operation after 1995. The potential for the conversion of the thermal power coming from liquid-dominated geothermal reservoirs, waste heat from primary engines or industrial processes, biomass combustion, and concentrated solar radiation into electricity is arguably enormous. ORC technology is possibly the most flexible in terms of capacity and temperature level and is currently often the only applicable technology for the conversion of external thermal energy sources. In addition, ORC power systems are suitable for the cogeneration of heating and/or cooling, another advantage in the framework of distributed power generation. Related research and development is therefore very lively. These considerations motivated the effort documented in this article, aimed at providing consistent information about the evolution, state, and future of this power conversion technology. First, basic theoretical elements on the thermodynamic cycle, working fluid, and design aspects are illustrated, together with an evaluation of the advantages and disadvantages in comparison to competing technologies. An overview of the long history of the development of ORC power systems follows, in order to place the more recent evolution into perspective. Then, a compendium of the many aspects of the state of the art is illustrated: the solutions currently adopted in commercial plants and the main-stream applications, including information about exemplary installations. A classification and terminology for ORC power plants are proposed. An outlook on the many research and development activities is provided, whereby information on new high-impact applications, such as automotive heat recovery is included. Possible directions of future developments are highlighted, ranging from efforts targeting volume-produced stationary and mobile mini-ORC systems with a power output of few kWe, up to large MWe base-load ORC plants.

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Organic Rankine Cycle Power Systems: From the Concept to Current Technology, Applications, and an Outlook to the Future

A process and system which integrates on-site heavy oil or bitumen upgrading and energy recovery for steam production with steam-assisted gravity drainage (SAGD) production of the heavy oil or bitumen. The heavy oil or bitumen produced by SAGD is flashed to remove the gas oil fraction, and the residue is solvent deasphalted to obtain deasphalted oil, which is mixed with the gas oil fraction to form a pumpable synthetic crude. The synthetic crude has an improvement of 4-5 degrees of API and lower in sulfur, nitrogen and metal compounds. The synthetic crude is not only more valuable than the heavy oil or bitumen, but also has substantial economic advantage of reducing the diluent requirement since it has lower viscosity than the heavy oil or bitumen. The asphaltenes, following an optional pelletizing and/or slurrying step, are used as a fuel for combustion in boilers near the steam injection wells for injection into the heavy oil or bitumen reservoir. This eliminates the need for natural gas or other fuel to produce steam at reservoir location and thus improves the economics of the heavy oil or bitumen production substantially. Alternatively, the asphaltenes are used as a feedstock for gasification to produce injection steam, synthesis gas. The CO2 could be used as additive with injection steam to enhance the performance of SAGD and the hydrogen could be exported to nearby processing facility. The invention upgrades the heavy oil or bitumen to a synthetic crude of improved value that can be pipelined with reduced amount of diluent, while at the same time using the asphaltene fraction of the residue for combustion to fulfill the energy requirements for generating injection steam for SAGD.

Field upgrading of heavy oil and bitumen

A method for operating a gas turbine engine (10), including a first compressor (14), a second compressor (16), and a turbine (20), coupled together in serial flow arrangement. The method includes channeling compressed airflow (53) discharged from the first compressor through an intercooler (50) having a cooling medium flowing therethrough, operating the intercooler such that condensate is formed in the intercooler from the compressed airflow, and channeling the condensate to an inlet (26,30) of the first or second compressor to facilitate reducing an operating temperature of the gas turbine engine.

Methods and apparatus for operating gas turbine engines

A heat recovery method and system that extracts heat from the exhaust of a gas turbine unit in a waste heat, heat exchanger and transfers the heat to an intermediate fluid, which can be pressurized water The intermediate fluid in-turn transfers the heat to an organic working fluid resulting in the vaporization thereof The vaporized organic working fluid drives a series of turbines which in turn drive a generator that generates electricity

Waste heat recovery in an organic energy converter using an intermediate liquid cycle

Retrofit equipment includes an auxiliary gas turbine unit including an auxiliary compressor for compressing ambient air to produce compressed air, a solar collector that receives the compressed air for heating the same to produce heated compressed air, and an auxiliary turbine coupled to the auxiliary compressor and to an auxiliary generator for expanding the heated compressed air and driving the auxiliary compressor and auxiliary generator thereby producing power and hot exhaust gases. When solar insolation is available, a flow control selectively supplies the hot exhaust gases from the retrofit equipment to a boiler which is part of a conventional fossil fueled power plant. The boiler has heat exchanger coils containing water and receives hot exhaust gases for vaporizing water in the coils and producing steam which is supplied to a steam turbine coupled to a generator for expanding steam produced by the boiler, and driving the generator and producing power and expanded steam. A condenser condenses the expanded steam to condensate, and a pump returns the condensate to the boiler. When solar insolation is not available. e.g., during the night, the flow control supplies the boiler with hot gases from a primary gas turbine unit which includes a primary compressor that compresses ambient air to produce compressed air, and a combustor that receives the compressed air for burning fossil fuel and heating the compressed air to produce heated compressed air that is supplied to the primary turbine.

Retrofit equipment for reducing the consumption of fossil fuel by a power plant using solar insolation

An externally fired gas turbine system according to the present invention has a compressor for compressing ambient air and producing compressed air, an air heat exchanger for heating the compressed air to produce heated compressed air, a turbine for expanding the heated compressed air to produce heat depleted expanded air, and a generator connected to the turbine for generating electricity. According to the present invention, the system also includes combustible products producing apparatus for processing fuel to produce combustible products that include combustible gases and an external combustion chamber for burning the combustible products and transferring heat to the air heat exchanger and producing heat depleted combustion products. The system also includes a closed Rankine cycle steam power plant having a water heat exchanger for vaporizing water and producing steam using heat contained in the heat depleted combustion products. The power plant further includes a steam turbine for expanding the steam producing power and expanded steam, and a steam condenser for condensing the expanded steam producing condensate that is returned to the water heat exchanger.

Externally fired combined cycle gas turbine system

The cooling of a hot fluid is effected using a heat exchanger (11) adapted to receive the hot fluid and liquid coolant for cooling the hot fluid such that the liquid coolant is vaporized. A turbine (12), having an output shaft (19) connected to a fan (18), is responsive to vaporized coolant which expands in the turbine (12) for driving the fan (18) to move a mass of air, and produce vaporized coolant. A condenser (13) receives the expanded vaporized coolant and is responsive to air blown by the fan (18), for condensing the expanded vaporized coolant thereby cooling the same and producing coolant condensate which is then returned to the heat exchanger (11).

Method and apparatus for cooling hot fluids

The present invention provides a method of and apparatus for producing power from solar energy wherein a solar collector heats gas supplied to a gas turbine; compressors compress the gas, the gas being compressed and stored gas during a first period of time, with the stored compressed gas being supplied to the gas turbine during a second period of time to produce power by driving an electric generator Preferably, the first period of time is during periods of off-peak electricity, which normally occur at night The second period of time is during the day The solar collector preferably comprises tracking reflectors for focusing solar radiation and a receiver for receiving the focused solar radiation and also heating the gas The solar radiation receiver preferably comprises a rotating ceramic member Furthermore, a combustion chamber is preferably provided to heat the gas entering the gas turbine and is operated by a temperature sensing/control unit when the solar radiation received by the receiver is insufficient to heat the gas entering the gas turbine to the required temperature The electric motor used to operate the compressors preferably comprises the electric generator of the gas turbine Furthermore, heat generated during the compression of the gas and contained therein is transferred to another fluid in a heat exchanger which comprises part of waste heat converter for producing electrical power therefrom

Lucien Y. Bronicki

Papers

Waste heat recovery in an organic energy converter using an intermediate liquid cycle

Retrofit equipment for reducing the consumption of fossil fuel by a power plant using solar insolation

Externally fired combined cycle gas turbine system

Method and apparatus for cooling hot fluids

Method of and apparatus for producing power from solar energy