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US 8,739,512 B2Granted
Combined cycle power plant
AssigneeAreva Solar, Inc.
InventorDavid R. Mills
Life of this patent
Estimating the term…
Abstract
Combined cycle power plants and related methods are disclosed here. In the plants, a mediating thermal energy storage unit is used to store waste or residual thermal energy recovered from a heat engine employing a top thermodynamic cycle of the combined cycle power plant, so that the stored residual thermal energy may be used as an energy source in a bottom thermodynamic cycle of the power plant. In the combined cycle power plants described here, the heat engine employing a top cycle may comprise a Brayton cycle heat engine and the heat engine employing the bottom thermodynamic cycle may be a Rankine cycle heat engine.
Claims39
A method of generating electrical energy, the method comprising:
- employing a top thermodynamic cycle comprising the steps of:
- heating a refractory material of a receiver with a concentrated solar light beam and storing the heat in the refractory material, the refractory material being selected from the group consisting of refractory metal, ceramic, cermet, alumina, silica, magnesia, zirconia, silicon carbide, titanium carbide, tantalum carbide, chromium carbide, niobium carbide, zirconium carbide, molybdenum disilicide, calcium oxide, chromite, dolomite, magnesite, quartzite, aluminium silicate, tungsten, molybdenum, niobium, tantalum, rhenium, beryllium, and combinations thereof;
- compressing a first working fluid;
- heating the first working fluid by passing it through the heated refractory material;
- and
- expanding the first working fluid in a turbine to generate electrical energy in a first generator;
- transferring at least a portion of the thermal energy from the first working fluid after expansion to a mediating thermal storage unit by passing exhaust from the turbine through the thermal storage unit to build up a store of residual thermal energy;
- and
- transferring the stored residual thermal energy from the mediating thermal storage unit and the stored heat in the refractory material to a second working fluid at a later time for use in a bottom thermodynamic cycle to generate electrical energy in a second generator, wherein the thermal storage unit is in the form of an aggregate, a powder, a solid mass or a liquid and comprises a material selected from the group consisting of rocks, minerals, quartz, aggregates, sand, concrete, molten salts including nitrate salts, hydroxide salt, carbonate salt, sulphate salt and combinations thereof.
6 more elements
An electrical power plant comprising:
- a solar concentrator for concentrating a solar light beam;
- a receiver comprising a refractory material for receiving the concentrated solar light beam and converting the concentrated solar light beam to heat energy and storing the heat energy, the refractory material being selected from the group consisting of refractory metal, ceramic, cermet, alumina, silica, magnesia, zirconia, silicon carbide, titanium carbide, tantalum carbide, chromium carbide, niobium carbide, zirconium carbide, molybdenum disilicide, calcium oxide, chromite, dolomite, magnesite, quartzite, aluminium silicate, tungsten, molybdenum, niobium, tantalum, rhenium, beryllium, and combinations thereof;
- a first top cycle heat engine employing a top thermodynamic cycle configured to generate electrical energy, the first top cycle heat engine comprising:
- a first compressor configured to compress a first working fluid;
- a first heating stage for heating the compressed first working fluid via the refractory material;
- and
- a first turbine configured to expand the first working fluid to drive a first generator;
- a mediating thermal energy storage unit configured to store residual thermal energy recovered from the expanded first working fluid of the first top cycle heat engine by passing exhaust from the first turbine through the thermal storage unit;
- a heat exchange apparatus operable to transfer heat from the heat stored in the refractory material and the mediating thermal energy storage unit to a second working fluid;
- a first bottom cycle heat engine employing a bottom thermodynamic cycle and configured to generate electrical energy using the second working fluid heated by the stored thermal energy in the refractory material and the mediating thermal energy storage unit, wherein the thermal storage unit is in the form of an aggregate, a powder, a solid mass or a liquid and comprises a material selected from the group consisting of rocks, minerals, quartz, aggregates, sand, concrete, molten salts including nitrate salts, hydroxide salt, carbonate salt, sulphate salt and combinations thereof.
7 more elements
An electrical power plant comprising a compressor to compress a first working fluid,
- a solar concentrator to form a concentrated light beam,
- a receiver comprising a refractory material for converting solar radiation from the concentrated light beam into heat and storing the heat to effect heating of the first working fluid following its compression, the refractory material being selected from the group consisting of refractory metal, ceramic, cermet, alumina, silica, magnesia, zirconia, silicon carbide, titanium carbide, tantalum carbide, chromium carbide, niobium carbide, zirconium carbide, molybdenum disilicide, calcium oxide, chromite, dolomite, magnesite, quartzite, aluminium silicate, tungsten, molybdenum, niobium, tantalum, rhenium, beryllium, and combinations thereof,
- a first turbine coupled to a first electrical generator for generating electrical energy, wherein the first working fluid in operation expands through the first turbine to drive the first electrical generator,
- a thermal energy storage unit arranged to store residual thermal energy contained in the first working fluid following its expansion through the first turbine by passing exhaust from the first turbine through the thermal storage unit,
- a second turbine coupled to a second electrical generator and arranged to receive a second working fluid that in operation is expanded through the second turbine to drive the second generator, and
- wherein the second working fluid is in operation heated by use of stored thermal energy extracted from the thermal energy storage unit and the refractory material of the receiver, wherein the thermal storage unit is in the form of an aggregate, a powder, a solid mass or a liquid and comprises a material selected from the group consisting of rocks, minerals, quartz, aggregates, sand, concrete, molten salts including nitrate salts, hydroxide salt, carbonate salt, sulphate salt and combinations thereof.
3 more elements
Dependencies are inferred from the claim text.