Installation for storing thermal energy
View Patent ↗An installation for storing thermal energy is provided. The storage is carried out by the compression and relaxation of a working gas, wherein pump and compressor can be driven by, for example, electric motors which temporarily absorb excess power generated in the power grid. The generated thermal energy is temporarily stored in a cold accumulator and a heat accumulator. According to the invention, a vapor circuit is provided to connect to the heat accumulator and the cold accumulator for discharging the installation, by which a turbine for generating electrical energy can be driven by a generator. Said circuit is implemented by means of another conduit system distinct from the circuit for charging the installation. Advantageously, thermal energy generated from overcapacities in the power grid can thus be reconverted with high yield into electrical energy via a vapor circuit.
1. An installation for storing thermal energy, said installation comprising:
a charging circuit for a working gas, wherein, in the charging circuit, the following are connected to one another in the stated sequence by a first circuit for the working gas:
a first thermal fluid energy machine,
a heat accumulator comprising a length, and
a second thermal fluid energy machine,
wherein, as viewed in a throughflow direction of the working gas from the first thermal fluid energy machine to the second thermal fluid energy machine, the first thermal fluid energy machine is a work machine and the second thermal fluid energy machine is a prime mover,
wherein the heat accumulator is connected, via a second circuit, into a discharging circuit for steam as working medium, wherein, in the discharging circuit, the following units are connected to one another in the stated sequence by the second circuit:
a pump,
the heat accumulator, and
a third thermal fluid energy machine as a prime mover,
wherein the working medium passes through the heat accumulator for the whole length of the heat accumulator; and
an auxiliary heat accumulator connected between a fifth thermal fluid energy machine and a sixth thermal fluid energy machine by an auxiliary circuit, wherein the auxiliary circuit from the fifth thermal fluid energy machine to the auxiliary heat accumulator and from the auxiliary heat accumulator to the sixth thermal fluid energy machine is discrete from the first circuit and the second circuit, and wherein the fifth thermal fluid energy machine is a work machine and the sixth thermal fluid energy machine is a prime mover.
2. The installation as claimed in claim 1 , wherein
the heat accumulator is traversed by flow in opposite directions in the charging circuit and in the discharging circuit.
3. The installation as claimed in claim 1 , wherein
the heat accumulator comprises a storage medium and a first duct system disposed in the storage medium and connected to the first circuit and has an independent second duct system disposed in the storage medium and connected to the second circuit.
4. The installation as claimed in claim 3 , wherein
the first duct system and the second duct system are formed by pipes running parallel, wherein each pipe belonging to the first duct system runs adjacent to at least one pipe of the second duct system.
5. The installation as claimed in claim 1 , wherein
the third thermal fluid energy machine is of at least two-stage construction with a high-pressure turbine and a low-pressure turbine.
6. The installation as claimed in claim 5 , further comprising
a first closable bypass line connected in parallel with the high-pressure turbine in the second circuit.
7. The installation as claimed in claim 1 , further comprising
a cold accumulator connected into the first circuit downstream of the second thermal fluid energy machine as viewed in the throughflow direction of the charging circuit.
8. The installation as claimed in claim 7 , wherein
the cold accumulator is also connected into the second circuit downstream of the third thermal fluid energy machine as viewed in the throughflow direction of the discharging circuit.
9. The installation as claimed in claim 1 , wherein
the auxiliary heat accumulator is also connected into the first circuit so that the first circuit is configured to guide the working gas from the auxiliary heat accumulator to upstream of the first thermal fluid energy machine then to the heat accumulator then to the second thermal fluid energy machine.
10. The installation as claimed in claim 1 , wherein
the auxiliary heat accumulator is also connected into the second circuit so that the second circuit is configured to guide the working medium from the auxiliary heat accumulator then to the heat accumulator then to the third thermal fluid energy machine.
11. The installation as claimed in claim 5 , further comprising
a second closable bypass line connected into the second circuit in parallel with respect to the heat accumulator.
12. The installation as claimed in claim 1 , wherein the third thermal fluid energy machine is a steam turbine.
13. An installation for storing thermal energy, said installation comprising:
a charging circuit that fluidically connects a first flow of working gas to a first work machine, a heat accumulator comprising a storage medium, and a second prime mover in the stated sequence, wherein the storage medium is in thermal communication with the first flow of working gas when the first flow of working gas passes through the storage medium;
a discharging circuit that fluidically connects a working medium to a pump, the heat accumulator, and a third prime mover in the stated sequence, wherein the storage medium is in thermal communication with the working medium when the working medium passes through the storage medium; and
an auxiliary charging circuit that fluidically connects an auxiliary flow of working gas to a fifth work machine, an auxiliary heat accumulator, and a sixth prime mover in the stated sequence, wherein the auxiliary flow of working gas is discrete from the first flow of working gas and from the working medium.
14. The installation as claimed in claim 13 , wherein:
the auxiliary heat accumulator is connected into the charging circuit so that the charging circuit is configured to guide the first flow of working gas from the auxiliary heat accumulator to the first work machine then to the heat accumulator then to the second prime mover,
wherein the auxiliary heat accumulator comprises an auxiliary storage medium, and
wherein the auxiliary storage medium is in thermal communication with the auxiliary flow of working gas when the auxiliary flow of working gas passes through the auxiliary storage medium.
15. The installation as claimed in claim 13 , wherein the charging circuit and the auxiliary charging circuit share a line through the auxiliary heat accumulator and are discrete from each other elsewhere.
16. The installation as claimed in claim 13 , wherein the charging circuit and the auxiliary charging circuit are fully discrete from each other.
17. The installation as claimed in claim 13 , wherein the storage medium comprises a solid material.
18. An installation for storing thermal energy, said installation comprising
a charging circuit for a working gas, wherein, in the charging circuit, the following are connected to one another in the stated sequence by a first circuit for the working gas:
a first thermal fluid energy machine,
a heat accumulator comprising a solid heat storage medium, a length from a first side to an opposite side of the solid heat storage medium, a first duct system comprising a first pipe oriented parallel to the length and connected to the first circuit, and a second duct system comprising a second pipe oriented parallel to the length, and
a second thermal fluid energy machine,
wherein, as viewed in a throughflow direction of the working gas from the first thermal fluid energy machine to the second thermal fluid energy machine, the first thermal fluid energy machine is a work machine and the second thermal fluid energy machine is a prime mover,
wherein the second duct system of the heat accumulator is connected, via a second circuit, into a discharging circuit for steam as working medium, wherein, in the discharging circuit, the following units are connected to one another in the stated sequence by the second circuit:
a pump,
the heat accumulator, and
a third thermal fluid energy machine as a prime mover,
wherein the working medium passes through the heat accumulator for the whole length of the heat accumulator, and
wherein the working gas flows through the first duct system in the solid heat storage medium in a first direction and the working medium flows through the second duct system in the solid heat storage medium in an opposite direction, effective to create homogenous heating in a cross-sectional area of the solid heat storage medium perpendicular to the length, and effective to create a cold-hot front which travels along the length in opposite directions during charging and discharging respectively.