WO2013079087A1 - Solar thermal power plant with supercritical working fluid for converting solar energy into electrical energy and method for converting solar energy into electrical energy - Google Patents
Solar thermal power plant with supercritical working fluid for converting solar energy into electrical energy and method for converting solar energy into electrical energy Download PDFInfo
- Publication number
- WO2013079087A1 WO2013079087A1 PCT/EP2011/071177 EP2011071177W WO2013079087A1 WO 2013079087 A1 WO2013079087 A1 WO 2013079087A1 EP 2011071177 W EP2011071177 W EP 2011071177W WO 2013079087 A1 WO2013079087 A1 WO 2013079087A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- energy
- solar
- power plant
- working fluid
- thermal power
- Prior art date
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F22—STEAM GENERATION
- F22B—METHODS OF STEAM GENERATION; STEAM BOILERS
- F22B3/00—Other methods of steam generation; Steam boilers not provided for in other groups of this subclass
- F22B3/08—Other methods of steam generation; Steam boilers not provided for in other groups of this subclass at critical or supercritical pressure values
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01K—STEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
- F01K3/00—Plants characterised by the use of steam or heat accumulators, or intermediate steam heaters, therein
- F01K3/18—Plants characterised by the use of steam or heat accumulators, or intermediate steam heaters, therein having heaters
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F22—STEAM GENERATION
- F22B—METHODS OF STEAM GENERATION; STEAM BOILERS
- F22B1/00—Methods of steam generation characterised by form of heating method
- F22B1/006—Methods of steam generation characterised by form of heating method using solar heat
Definitions
- This invention relates to a solar thermal power plant for converting solar energy into electrical energy and a method for converting solar energy into electrical energy.
- Solar thermal power plants like solar power towers or parabolic trough and Linear Fresnel are expected to be able to cover a significant portion of the increasing world's demand for energy in the upcoming decades. These solar thermal power plants generate carbon dioxide-free electricity by the transformation of solar light radiation into thermal energy.
- steam is generated with the aid of the thermal energy (Steam/water cycle) .
- the steam drives a turbine which is coupled to a generator.
- the generator generates electricity which is finally supplied to a grid.
- the transport of heat from sun radiation to the water/steam- cycle of the power block is realized by means of a heat transfer fluid (HTF) .
- the heat transfer fluid is a thermo-oil or molten salt.
- the heat transfer fluid is water.
- steam can be directly produces. This concept is called Direct Steam Generation (DSG)
- This concept is based on a dual-phase flow (i.e. sub-critical water) inside solar receivers and piping systems of the solar thermal power plant. Water in liquid phase is heated up by the thermal energy which is absorbed using the solar receivers and become saturated water/steam. This saturated water/steam is heated up to super-heated steam.
- - Evaporation stage for transferring all saturated water into gas phase.
- This stage is characterized by a constant temperature process.
- This stage is done usually by a latent heat based TES (thermal energy storage ) -system .
- - Super-Heating stage (high temperature stage) for heating the saturated steam into superheated steam.
- This stage is done usually by a sensible based TES system.
- a further object of the invention is to provide a method for converting solar energy into electrical energy by using the solar thermal power plant.
- a solar thermal power plant for converting solar energy into electrical energy comprises at least one solar energy absorber unit for absorb ⁇ ing the solar energy and for converting absorbed solar energy into thermal energy of a working fluid of the solar energy absorber unit and at least one converter unit (power generation unit) for converting the thermal energy of the working fluid into the electrical energy, wherein the working fluid is a supercritical fluid.
- a method for converting solar energy into elec ⁇ trical energy by using the solar thermal power plant wherein the solar energy is converted into thermal en- ergy of the working fluid and the thermal energy of the working fluid is converted into electrical energy.
- the converter unit comprises at least one turbine.
- the work- ing fluid drives the turbine, which is coupled to at least one generator.
- the working fluid, which is used to drive the turbine is the same working fluid, which absorbs the solar energy. There is no heat exchanger.
- This system is like the direct steam generation system with the difference that a su- percritical fluid is used.
- the supercritical fluid is any substance at a temperature and pressure above its critical point. At the critical point of the substance there is no distinction between a liquid phase and a gas phase of the substance. It can effuse like a gas and dissolve materials like a liquid. Characteristics of a supercritical fluid can vary in wide ranges. For instance, the density of supercritical fluids can be out of a range of 100 kg/m 3 - 1000 kg/m 3 . In comparison to that: Gases have a density of about 1 kg/m 3 and liquids (e.g. water) of about 1000 kg/m 3 . 3 .
- the supercritical fluid can be carbon dioxide (CO2) ⁇
- the supercritical fluid is supercritical water.
- the critical temperature of water is about 647.1° K and the critical pressure is about 22 MPa.
- Supercritical water is produced in the absorber unit and is used as working fluid of the generator unit.
- at least one solar radiation concentrating unit is installed for concentrating solar radiation in a focus of the solar radiation concentrating unit, wherein the absorber unit is located in the focus of the solar radiation concentrating unit.
- the focus of the solar radiation concentrating units is a focal line a parabolic trough collector, a Linear Fresnel collector or a power central receiver .
- the focus unit is for instance a heliostat.
- the solar radiation concentrating unit is selected from the group consisting of parabolic trough collector, Linear Fresnel collector and/or central receiver.
- the absorber unit comprises for instance at least one absorber tube for carrying the working fluid and the absorber tube is located in the focus of the solar radiation concentrating unit.
- the absorber tube solar radiation is absorbed and converted to thermal energy. This thermal energy is used to produce the supercritical fluid.
- a single stage thermal storage unit is installed for providing dispatchable thermal energy for producing supercritical fluid which can act as a working fluid.
- the single stage thermal storage unit comprises a storage material with one single stable phase in the working region. By the thermal storage unit thermal energy can be absorbed and can be delivered.
- the characteristics of a supercritical fluid can vary in a wide range.
- the figure shows an extract of a solar thermal power plant according to the invention.
- the solar thermal power plant 1 comprises at least one solar energy absorber unit 2 for absorbing the solar energy and for converting absorbed solar energy into thermal energy of a working fluid of the solar energy absorber unit and at least one converter unit 3 for converting the thermal energy of the working fluid into the electrical energy, wherein the working fluid is a supercritical fluid.
- the supercritical fluid is supercritical water.
- a solar radiation concentrating unit 4 is a parabolic through collector.
- the solar radiation concentrating unit is a Linear Fresnel collector.
- In a focal line 41 of the parabolic trough collector an absorber tube 42 of the absorber unit is arranged. With the aid of the parabolic trough collector sunlight radiation is concentrated in its focal line. With the aid of the absorber tube supercritical water is produced in the interior of the absorber tube.
- the absorber tube is a part of the complete tube assembly.
- the generator unit 3 comprises a turbine which is driven by the supercritical water. A coupling of the turbine with a generator leads to electricity .
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Sustainable Energy (AREA)
- Sustainable Development (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Engine Equipment That Uses Special Cycles (AREA)
Abstract
A solar thermal power plant for converting solar energy into electrical energy is provided. The solar thermal power plant comprises at least one solar energy absorber unit for absorbing the solar energy and for converting absorbed solar energy into thermal energy of a working fluid of the solar energy absorber unit and at least one converter unit for converting the thermal energy of the working fluid into the electrical energy, wherein the working fluid is a supercritical fluid. The supercritical fluid is preferably supercritical water. Additionally a method for converting solar energy into electrical energy by using the solar thermal power plant is provided, wherein the solar energy is converted into thermal energy of the working fluid and the thermal energy of the working fluid is converted into electrical energy.
Description
Description
SOLAR THERMAL POWER PLANT WITH SUPERCRITICAL WORKING FLUID FOR CONVERTING SOLAR ENERGY INTO ELECTRICAL ENERGY AND METHOD FOR CONVERTING SOLAR ENERGY INTO ELECTRICAL ENERGY
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a solar thermal power plant for converting solar energy into electrical energy and a method for converting solar energy into electrical energy. 2. Description of the Related Art
Solar thermal power plants like solar power towers or parabolic trough and Linear Fresnel are expected to be able to cover a significant portion of the increasing world's demand for energy in the upcoming decades. These solar thermal power plants generate carbon dioxide-free electricity by the transformation of solar light radiation into thermal energy.
In a power block of the solar thermal power plant steam is generated with the aid of the thermal energy (Steam/water cycle) . The steam drives a turbine which is coupled to a generator. The generator generates electricity which is finally supplied to a grid. The transport of heat from sun radiation to the water/steam- cycle of the power block is realized by means of a heat transfer fluid (HTF) . The heat transfer fluid is a thermo-oil or molten salt. With the aid of a heat exchanger the thermal
energy is transferred to water of the water/steam cycle of the power block.
Ideally, the heat transfer fluid is water. By this, the use of the heat exchanger is not necessary. Steam can be directly produces. This concept is called Direct Steam Generation (DSG)
This concept is based on a dual-phase flow (i.e. sub-critical water) inside solar receivers and piping systems of the solar thermal power plant. Water in liquid phase is heated up by the thermal energy which is absorbed using the solar receivers and become saturated water/steam. This saturated water/steam is heated up to super-heated steam.
In the dual phase DSG concept matching a thermal energy stor¬ age (TES) system is quite a challenge. This is caused by the condensation and evaporation stage of the water that takes place at a constant temperature while it consists of a major portion of the energy. In order to get an effective TES system for that dual phase DSG concept it is necessary to split up the TES system into three stages. Each stage will be used for a different water heating stage: - Preheating stage (low temperature stage) for heating the water up to its phase changing point. This stage is done usually by a sensible based TES system.
- Evaporation stage for transferring all saturated water into gas phase. This stage is characterized by a constant temperature process. This stage is done usually by a latent heat based TES (thermal energy storage ) -system .
- Super-Heating stage (high temperature stage) for heating the saturated steam into superheated steam. This stage is done usually by a sensible based TES system. Implementing a three stages TES system makes this system very complex. Moreover such a system is not economic.
SUMMARY OF THE INVENTION It is an object of the invention to provide a solar thermal power plant for which a TES system is available, which is less complex compared to that of the state of the art.
A further object of the invention is to provide a method for converting solar energy into electrical energy by using the solar thermal power plant.
These objects are achieved by the inventions- specified in the claims .
A solar thermal power plant for converting solar energy into electrical energy is provided. The solar thermal power plant comprises at least one solar energy absorber unit for absorb¬ ing the solar energy and for converting absorbed solar energy into thermal energy of a working fluid of the solar energy absorber unit and at least one converter unit (power generation unit) for converting the thermal energy of the working fluid into the electrical energy, wherein the working fluid is a supercritical fluid.
Additionally a method for converting solar energy into elec¬ trical energy by using the solar thermal power plant is provided, wherein the solar energy is converted into thermal en-
ergy of the working fluid and the thermal energy of the working fluid is converted into electrical energy.
The converter unit comprises at least one turbine. The work- ing fluid drives the turbine, which is coupled to at least one generator. The working fluid, which is used to drive the turbine is the same working fluid, which absorbs the solar energy. There is no heat exchanger. This system is like the direct steam generation system with the difference that a su- percritical fluid is used.
The supercritical fluid is any substance at a temperature and pressure above its critical point. At the critical point of the substance there is no distinction between a liquid phase and a gas phase of the substance. It can effuse like a gas and dissolve materials like a liquid. Characteristics of a supercritical fluid can vary in wide ranges. For instance, the density of supercritical fluids can be out of a range of 100 kg/m3 - 1000 kg/m3. In comparison to that: Gases have a density of about 1 kg/m3 and liquids (e.g. water) of about 1000 kg/m3.3.
The supercritical fluid can be carbon dioxide (CO2) · In a preferred embodiment the supercritical fluid is supercritical water. The critical temperature of water is about 647.1° K and the critical pressure is about 22 MPa. Supercritical water is produced in the absorber unit and is used as working fluid of the generator unit. In a further embodiment at least one solar radiation concentrating unit is installed for concentrating solar radiation in a focus of the solar radiation concentrating unit, wherein the absorber unit is located in the focus of the solar radiation concentrating unit. The focus of the solar radiation
concentrating units is a focal line a parabolic trough collector, a Linear Fresnel collector or a power central receiver . The focus unit is for instance a heliostat. In a preferred embodiment the solar radiation concentrating unit is selected from the group consisting of parabolic trough collector, Linear Fresnel collector and/or central receiver. By this the absorber unit comprises for instance at least one absorber tube for carrying the working fluid and the absorber tube is located in the focus of the solar radiation concentrating unit. By the absorber tube solar radiation is absorbed and converted to thermal energy. This thermal energy is used to produce the supercritical fluid.
In a further embodiment a single stage thermal storage unit is installed for providing dispatchable thermal energy for producing supercritical fluid which can act as a working fluid. The single stage thermal storage unit comprises a storage material with one single stable phase in the working region. By the thermal storage unit thermal energy can be absorbed and can be delivered.
Summarizing following advantages are provided by the inven- tion:
- By using supercritical fluid as a working fluid there are no three stages necessary for the implementation of a TES system.
- The characteristics of a supercritical fluid can vary in a wide range.
BRIEF DESCRIPTION OF THE SCHEMATIC DRAWINGS
Further features and advantages of the invention are produced from the description of an exemplary embodiment with reference to the drawings. The drawings are schematic.
The figure shows an extract of a solar thermal power plant according to the invention.
With the aid of the solar thermal power plant 1 solar energy (solar radiation is converted into electrical energy. The solar thermal power plant 1 comprises at least one solar energy absorber unit 2 for absorbing the solar energy and for converting absorbed solar energy into thermal energy of a working fluid of the solar energy absorber unit and at least one converter unit 3 for converting the thermal energy of the working fluid into the electrical energy, wherein the working fluid is a supercritical fluid. The supercritical fluid is supercritical water. Additionally there is a solar radiation concentrating unit 4. The solar radiation concentrating unit is a parabolic through collector. In an alternative embodiment the solar radiation concentrating unit is a Linear Fresnel collector. In a focal line 41 of the parabolic trough collector an absorber tube 42 of the absorber unit is arranged. With the aid of the parabolic trough collector sunlight radiation is concentrated in its focal line. With the aid of the absorber tube supercritical water is produced in the interior of the absorber tube.
The absorber tube is a part of the complete tube assembly. By the tube assembly the supercritical water is piped to the generator unit (power generation unit) 3. The generator unit
3 comprises a turbine which is driven by the supercritical water. A coupling of the turbine with a generator leads to electricity .
Claims
1. Solar thermal power plant (1) for converting solar energy into electrical energy with
- at least one solar energy absorber unit (2) for absorbing the solar energy and for converting absorbed solar energy into thermal energy of a working fluid of the solar energy absorber unit and
- at least one converter unit (3) for converting the thermal energy of the working fluid into the electrical energy, wherein
- the working fluid is a supercritical fluid.
2. Solar thermal power plant according to claim 1, wherein the supercritical fluid is supercritical water.
3. Solar thermal power plant according to claim 1 or 2, wherein at least one solar radiation concentrating unit (4) is installed for concentrating solar radiation in a focus (41) of the solar radiation concentrating unit (4) , wherein the absorber unit is located in the focus of the solar radiation concentrating unit.
4. Solar thermal power plant according to claim 3, wherein the solar radiation concentrating unit (4) is selected from the group consisting of parabolic trough collector, Linear Fresnel collector and/or central receiver.
5. Solar thermal power plant according to one of the claims 1 to 4, wherein the absorber unit (2) comprises at least one absorber tube (42) for carrying the working fluid and the absorber tube is located in the focus (41) of the solar radiation concentrating unit (4) .
6. Solar thermal power plant according to one of the claims 1 to 5, wherein a single stage thermal storage unit is installed for providing dispatchable thermal energy for producing supercritical fluid which can act as a working fluid.
7. Method for converting solar energy into electrical energy by using the solar thermal power plant according to claim 1 to 6, wherein the solar energy is converted into thermal en¬ ergy of the working fluid and the thermal energy of the work- ing fluid is converted into electrical energy.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| PCT/EP2011/071177 WO2013079087A1 (en) | 2011-11-28 | 2011-11-28 | Solar thermal power plant with supercritical working fluid for converting solar energy into electrical energy and method for converting solar energy into electrical energy |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| PCT/EP2011/071177 WO2013079087A1 (en) | 2011-11-28 | 2011-11-28 | Solar thermal power plant with supercritical working fluid for converting solar energy into electrical energy and method for converting solar energy into electrical energy |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| WO2013079087A1 true WO2013079087A1 (en) | 2013-06-06 |
Family
ID=45099071
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| PCT/EP2011/071177 WO2013079087A1 (en) | 2011-11-28 | 2011-11-28 | Solar thermal power plant with supercritical working fluid for converting solar energy into electrical energy and method for converting solar energy into electrical energy |
Country Status (1)
| Country | Link |
|---|---|
| WO (1) | WO2013079087A1 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2529001A (en) * | 2014-08-03 | 2016-02-10 | Stephen Desmond Lewis | Reduced cost solar generator |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE4121460A1 (en) * | 1991-06-28 | 1993-01-14 | Deutsche Forsch Luft Raumfahrt | HEAT STORAGE SYSTEM WITH COMBINED HEAT STORAGE |
| DE10008123A1 (en) * | 1999-02-22 | 2001-08-23 | Frank Eckert | ORC energy conversion apparatus useful for generating electricity comprises one or more solar collectors employing an organic heat-transfer medium |
| DE10039989A1 (en) * | 2000-08-16 | 2002-03-14 | Rainer Rittmann | Non-conventional energy source power generation method using heat e.g. solar energy, involves heating coolant for expansion to rise in riser pipe and making liquid fall in falling tube to drive turbine |
| EP2131105A1 (en) * | 2008-06-05 | 2009-12-09 | L'Air Liquide Société Anonyme pour l'Etude et l'Exploitation des Procédés Georges Claude | Process to convert low grade heat source into power using a two-phase fluid expander |
| WO2009147651A2 (en) * | 2008-06-06 | 2009-12-10 | Xelos S.R.L. | A solar energy generator |
| US20100083658A1 (en) * | 2005-09-21 | 2010-04-08 | Solartrec Inc. | Heat engine improvements |
-
2011
- 2011-11-28 WO PCT/EP2011/071177 patent/WO2013079087A1/en active Application Filing
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE4121460A1 (en) * | 1991-06-28 | 1993-01-14 | Deutsche Forsch Luft Raumfahrt | HEAT STORAGE SYSTEM WITH COMBINED HEAT STORAGE |
| DE10008123A1 (en) * | 1999-02-22 | 2001-08-23 | Frank Eckert | ORC energy conversion apparatus useful for generating electricity comprises one or more solar collectors employing an organic heat-transfer medium |
| DE10039989A1 (en) * | 2000-08-16 | 2002-03-14 | Rainer Rittmann | Non-conventional energy source power generation method using heat e.g. solar energy, involves heating coolant for expansion to rise in riser pipe and making liquid fall in falling tube to drive turbine |
| US20100083658A1 (en) * | 2005-09-21 | 2010-04-08 | Solartrec Inc. | Heat engine improvements |
| EP2131105A1 (en) * | 2008-06-05 | 2009-12-09 | L'Air Liquide Société Anonyme pour l'Etude et l'Exploitation des Procédés Georges Claude | Process to convert low grade heat source into power using a two-phase fluid expander |
| WO2009147651A2 (en) * | 2008-06-06 | 2009-12-10 | Xelos S.R.L. | A solar energy generator |
Non-Patent Citations (1)
| Title |
|---|
| MULLER M ET AL: "KREISPROZESSSCHALTUNGEN FUR PARABOLRINNEN-SOLARKRAFTWERKE MIT DIREKTER DAMPFERZEUGUNG IM SOLARFELD", BWK BRENNSTOFF WARME KRAFT, SPRINGER VDI VERLAG, DUSSELDORF, DE, vol. 44, no. 10, 1 October 1992 (1992-10-01), pages 463 - 468, XP000540018, ISSN: 1618-193X * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2529001A (en) * | 2014-08-03 | 2016-02-10 | Stephen Desmond Lewis | Reduced cost solar generator |
| GB2529001B (en) * | 2014-08-03 | 2020-12-16 | Desmond Lewis Stephen | Reduced cost solar generator |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Wang et al. | Integration between supercritical CO2 Brayton cycles and molten salt solar power towers: A review and a comprehensive comparison of different cycle layouts | |
| US8039984B2 (en) | System for converting solar radiation into electricity | |
| US8365720B2 (en) | Solar concentration plant for the production of superheated steam | |
| US7171812B2 (en) | Electric generation facility and method employing solar technology | |
| US20120240577A1 (en) | Thermal generation systems | |
| CN103352814B (en) | Parabolic groove type composite power generation system with solar heat collector and chemical heat pump being combined together | |
| Pitz-Paal | Solar energy–concentrating solar power | |
| AU2010313242A1 (en) | Dual fluid circuit system for generating a vaporous working fluid using solar energy | |
| CN104832229A (en) | Britten-organic Rankine type solar thermal power generation method and device | |
| CN204691835U (en) | A kind of Boulez pauses-organic Rankine type solar energy thermal-power-generating device | |
| CN101852193A (en) | Concentrating solar power generation system | |
| Poullikkas et al. | Optimum sizing of steam turbines for concentrated solar power plants | |
| Krothapalli et al. | Concentrated solar thermal power | |
| JP2016217223A (en) | Solar thermal gas turbine power generation system | |
| CN102661259B (en) | Integrated solar thermal power generation system | |
| Han et al. | Performance enhancement of a solar trough power plant by integrating tower collectors | |
| US20130312413A1 (en) | Steam rankine cycle solar plant and method for operating such plants | |
| US20140216032A1 (en) | Solar direct steam generation power plant combined with heat storage unit | |
| CN201661433U (en) | Condensing solar power generation system | |
| WO2020029422A1 (en) | Disk type solar photothermal gradient utilization system | |
| WO2013079087A1 (en) | Solar thermal power plant with supercritical working fluid for converting solar energy into electrical energy and method for converting solar energy into electrical energy | |
| US20110162361A1 (en) | Method of superheating team | |
| CN107218185A (en) | A kind of disc type solar energy live (open) steam heat generating system based on classification accumulation of heat | |
| Abbas et al. | A quest to the cheapest method for electricity generation in Concentrating Solar Power plants | |
| CN202472105U (en) | Light field heat collection system for tower type solar energy thermal power plant |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| 121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 11791512 Country of ref document: EP Kind code of ref document: A1 |
|
| NENP | Non-entry into the national phase |
Ref country code: DE |
|
| 122 | Ep: pct application non-entry in european phase |
Ref document number: 11791512 Country of ref document: EP Kind code of ref document: A1 |