Combined cycle power plant

摘要

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.

主权项

1. 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.