DE102007013430B9 - Solar thermal power plant and method for operating a solar thermal power plant - Google Patents

Abstract

A solar thermal power plant, comprising a plurality of combustion line collectors (30; 34; 330; 334) each having an extension in a longitudinal direction, to which a heat transfer medium can be heated, characterized in that at least one first group (28a; 28b; 28c; 328) of Refueling collectors (30; 330) and a second group (32a; 32b; 32c; 332) of refueling collectors (34; 334) are provided, wherein the refueling collectors (30; 34; 330; 334) of each group (28a; 28b; 28c; 32a; 32b; 32c; 328; 332) are connected in series with respect to a guide direction of the heat transfer medium and have the same geographical orientation of their longitudinal direction, and that the focal line collectors (30; 330) of the first group (28a; 28b; 28c; 328) have a different longitudinal orientation than the focal line collectors (34; 334) of the second group (32a; 32b; 32c; 332).

Description

The invention relates to a solar thermal power plant, comprising a plurality of fuel line collectors each having an extension in a longitudinal direction, on which a heat transfer medium can be heated.

Furthermore, the invention relates to a method for operating a solar thermal power plant, which comprises a plurality of fuel line collectors each having an extension in a longitudinal direction, in which a heat transfer medium is fed to refiner collectors.

A solar thermal power plant, comprising a plurality of fuel line collectors each having an extension in a longitudinal direction, in which a heat transfer medium is heated, is for example from DE 101 28 562 C1 or the DE 101 52 971 C1 known.

A solar thermal power plant is further described in R. Osuna et al., Proceedings of ISES 2005 Solar World Congress, Orlando, Florida, USA, August 2005, which presents a concept for combining different power plant technologies.

The invention has for its object to improve a solar thermal power plant of the type mentioned above and a method for operating a solar thermal power plant of the type mentioned so that the efficiency of the power plant is optimized in the time average.

This object is achieved in a solar thermal power plant of the type described above according to the invention that at least a first group of fuel line collectors and a second group of fuel line collectors are provided, the fuel line collectors of each group are connected in series with respect to a guide direction of the heat transfer medium and the same geographical Have alignment of their longitudinal direction, and that the focal line collectors of the first group have a different geographical orientation of their longitudinal direction than the focal line collectors of the second group.

The power that can be generated from solar radiation at a given point in time by a fuel line collector group depends on the respective position of the sun and thus on the season and the time of day. The geographical orientation of the longitudinal direction of the fuel line collectors is crucial for their performance profile.

Refueling collectors with, for example, the north-south direction longitudinal direction received in the summer at noon, the largest solar radiation power (based on the year), in winter, however, a much lower maximum solar radiation power in the morning and afternoon. Refueling collectors with, for example, aligned in the west-east direction longitudinal direction received in summer as in winter at noon, the largest solar radiation power in the daily average in summer less and in winter more aligned with their longitudinal direction in north-south direction Brennlinienkollektoren.

By the presence of at least a first group of fuel line collectors and a second group of fuel line collectors, wherein the fuel line collectors of each group are connected in series with respect to a direction of the heat transfer medium and have the same geographic orientation of their longitudinal direction, and wherein the fuel line collectors of the first group another geographic orientation of their longitudinal direction than the focal line collectors of the second group, it is possible to carry out the heating of heat transfer medium at a given time in the first and / or the second group and optionally other groups and thereby the ability of the respective focal line collectors to receive solar radiation power to use this time.

As a result, the amount of water vapor supplied by the fuel line collectors in the course of time can be adjusted to the demand for water vapor caused by the further process control.

If, for example, fuel line collectors are used both for the evaporation of water and for overheating of the steam and the steam is then transferred to produce electrical energy in steam turbines, as steady a supply of steam turbines is necessary. This can at such times in which too little superheated steam from the fuel line collectors is available, by an additional firing or by cached amounts of energy that were previously obtained from surpluses from the fuel line collectors, guaranteed. These alternatives are each associated with high technical complexity.

In the solar thermal power plant according to the invention, the supply of superheated steam from the fuel line collectors can be stabilized. As a result, the turbines can be operated over a longer period of time with transferred from the fuel line collectors steam. There are fewer surpluses and / or deficits of superheated steam, which causes a Additional firing or caching given effort is reduced.

In a preferred embodiment, the first group and the second group are connected in parallel with respect to the guide direction of the heat transfer medium. In this combination, the amount of heat transfer medium passed through each of these groups can be adjusted to suit the particular energy intake capability of the group.

In a further preferred embodiment of the invention, the first group and the second group are connected in series with respect to the guide direction of the heat transfer medium. In this combination, when heating a given amount of the heat transfer medium, the respective capabilities of these groups of collectors for energy absorption can be used to advantage. For example, it is also possible to provide a third group whose focal-line collectors have the same geographical orientation of their longitudinal direction as that of the second group, the first group being connected in series with the second group in series and with the third group in relation to the guiding direction of the heat-transfer medium.

It is advantageous if the solar thermal power plant has a distribution device, through which at least two partial streams of the heat transfer medium for each at least one group can be generated. In this case, the relative size of the partial flows can be regulated easily.

Preferably, the solar thermal power plant has a collection device, through which the at least two partial streams can be collected to form a total flow. The further process control is less technically complicated with a remaining total current than with separately remaining partial flows.

Advantageously, the collection device is downstream of the fuel line collectors with respect to the guide direction of the heat transfer medium. This ensures that the entire heat transfer medium vaporized in the combustion line collectors can be transferred to the collection device.

Advantageously, the solar thermal power plant according to the invention has at least one recirculation device which is assigned to one or more groups. If more heat transfer medium is fed into the groups, as can be evaporated in these, can be returned by the recirculation device after passing through the groups remaining liquid heat transfer medium and transferred again into this. In this way, the dependence of the amount of steam supplied by the groups of fluctuations of the solar irradiation conditions is reduced.

Such a recirculation device can be assigned to a single group and return the leaked from this liquid heat transfer medium into it. It can also be assigned to a plurality of groups and supply the collected liquid heat transfer medium that has escaped from it to a distribution device, from which it is re-directed into individual groups.

Preferably, the geographical orientation of the longitudinal direction and / or the number of focal line collectors of the groups depending on the geographical location of the location of the solar thermal power plant. Due to the geographical location, the conditions of solar radiation at a location depending on the time of day as well as the season and thus also the performance profile of located at this location focal line collectors are defined with different geographical orientation of their longitudinal direction.

In particular, it is provided that a focal-line collector in each case has a focal region with an extension length in the longitudinal direction and an extension width transverse to the longitudinal direction, wherein the extension length is greater than the extension width. Preferably, focal line collectors are used in which the focus area is linear and in particular its extension length is at least five times greater than its extension width. Such focal line collectors are very well suited for the evaporation of heat transfer medium, which is passed through its focus area.

In a preferred embodiment, at least one focal line collector is designed as a parabolic trough collector. Parabolic trough collectors have been used in solar thermal power plants for decades. Their components could be extensively optimized during this time.

In a further preferred embodiment of the invention, at least one focal line collector is designed as a linear Fresnel collector. Fresnel panels comprise individual non-arched or slightly curved mirror strips and are therefore inexpensive to produce.

In particular, at least one tower receiver and at least one heliostat associated with the corresponding tower receiver are provided, wherein the heat transfer medium can be heated at combustion line collectors and subsequently at the at least one tower receiver.

Through the combination of focal line collectors (which form a first heating section) and a tower receiver with associated heliostat field (through which a second heating section is formed), the specific advantages of these heating sections can be combined. The heat transfer medium is evaporated, for example, to fuel line collectors and the steam is then overheated in the tower receiver. If the heat transfer medium is, for example, water, steam with a temperature of up to about 300 ° C. is generated in the fuel line collectors. The stresses occurring here due to high pressure and high temperatures are limited and it can be used on relatively inexpensive investment technique. The more expensive component of the tower receiver with the associated heliostat field on the other hand serves only to overheat the steam to temperatures up to about 600 ° C and can be significantly smaller dimensions than a tower receiver, in which the evaporation must be performed.

About the associated heliostats receives a tower receiver in the summer as in winter at noon, the largest solar radiation power and can overheat at this time, the largest amount of water vapor supplied to him. Accordingly, for the production of this water vapor provided Brennlinienkollektoren should also be able to exploit the largest solar radiation performance over the entire year at noon.

By the presence of a first group of fuel line collectors and a second group of fuel rail collectors, wherein the fuel line collectors of each group are connected in series with respect to a guide direction of the heat transfer medium and have the same geographic orientation of their longitudinal direction, and wherein the fuel line collectors of the first group have a different geographic orientation Their longitudinal direction than the focal line collectors of the second group, this requirement can be better met.

The amount of total supplied by the fuel line collectors steam can be approximated in the tower receiver at this time maximum überhitzbaren amount, so that fewer excess steam and / or -unterschüsse occur.

In the case of excess steam generated in the fuel line collectors, caching or alternative use is expensive technically and in terms of cost. It may be necessary to temporarily shut off at least parts of the fuel collector to avoid surpluses and thus to leave their potential for energy production unused. By reducing the surpluses in a solar thermal power plant according to the invention, the number of operating hours is increased in the course of the year, in which all existing fuel line collectors can be used.

The reduction of vapor defaults allows a better use of the potential of the tower receiver for energy production.

The amount of superheated steam supplied by the tower receiver is thus increased, so that the power plant can have a longer operating time in the course of a year.

If the superheated steam provided by a tower receiver is to be used, for example, in steam turbines to generate electrical energy, these are preferably dimensioned such that the tower receiver supplies more superheated steam in some time periods than can be processed in it. This excess of heat energy may then be stored in latches and provided to the turbines at times when the tower receiver provides a surplus of superheated steam. This storage is associated with energy losses.

In the solar thermal power plant according to the invention, the amount of superheated steam delivered by the tower receiver is less subject to fluctuations over time. As a result, for example, a larger proportion of this amount can be routed directly into turbines, and the energy losses associated with the intermediate storage are reduced.

Furthermore, the at least one tower receiver is advantageously preceded by a collecting device in relation to the guiding direction of the heat transfer medium. As a result, the collector collected in the collecting device can be supplied to the tower receiver.

Advantageously, the at least one tower receiver is associated with an injection device for liquid heat transfer medium. At a time when the tower receiver is capable of overheating larger amounts of vaporized heat transfer medium than can be provided by the fuel line collectors, the heat carrier medium additionally supplied in the injection device can prevent unacceptable solar energy absorbed by the tower receiver.

In a preferred embodiment, the fuel line collectors of the first group with their longitudinal direction aligned in north-south direction and aligned the focal line collectors of the second group with its longitudinal direction in west-east direction. Firing line collectors with these two orientations have time histories of their energy absorption capabilities that complement each other favorably. This combination is particularly suitable for providing a tower receiver with the amount of water vapor that it is capable of overheating at a given time.

Preferably, the ratio of the number of focal line collectors of the first group and / or the second group to the total number of focal line collectors is in the range between 20% and 80%. Such a relationship is appropriate for much of the potential locations for a solar thermal power plant.

Particularly preferably, the ratio is in the range between 40% and 60%. In model calculations for operating a solar thermal power plant according to the invention with a tower receiver in Sevilla, southern Spain, a ratio to the total number of fusible link collectors of approximately 50% each has proved to be particularly advantageous for the number of fuel line collectors of the first group and the second group.

It is provided a device for generating electrical energy. In such a device, the heat energy of the superheated medium can be partially converted into electrical energy.

In particular, the device for generating electrical energy comprises at least one steam turbine and at least one generator, wherein the at least one steam turbine is connected downstream of the fuel line collectors with respect to the guide direction of the heat transfer medium. Steam turbines are extensively optimized devices for generating electrical energy from the heat energy of a steam.

In a preferred embodiment, the at least one steam turbine is connected downstream of one or more tower receivers with respect to the guide direction of the heat transfer medium. This ensures that the steam turbine heat transfer medium is supplied, which has first taken on the fuel line collectors and subsequently to the at least one tower receiver high amounts of energy.

Advantageously, an additional heating device is provided. This can ensure that the amount of superheated steam required, for example, for operating a turbine is also generated when the amount of heat transfer medium heated in the combustion line collectors and optionally the tower receiver does not suffice.

Advantageously, the additional heating device comprises a fossil firing device. This can provide superheated steam at any time.

Preferably, a solar thermal power plant according to the invention has at least one heat storage. Also heat storage contribute to the fact that the amount of superheated steam provided in the solar thermal power plant varies as little as possible in time. Heat energy present in a heat accumulator can be released, for example, at night, when due to lack of solar radiation the fuel line collectors and possibly the tower receiver deliver too little steam.

Advantageously, the at least one heat accumulator is coupled via a heat transfer medium circuit with at least one steam turbine. Then, the energy stored in it can be delivered to the heat transfer medium, which is subsequently supplied directly to the at least one turbine.

For example, water is used as the heat transfer medium. Among other things, by the high heat absorption capacity of the water, it is particularly well suited to be evaporated in fuel line collectors and then overheated in a tower receiver.

The object mentioned in the introduction is achieved according to the invention in that a heat transfer medium is supplied to at least one first group of fuel line collectors and a second group of fuel line collectors, the fuel line collectors of each group being connected in series with respect to a guide direction of the heat transfer medium and the same geographic orientation of their longitudinal direction, and wherein the focal line collectors of the first group have a different geographical orientation of their longitudinal direction than the focal line collectors of the second group. As a result, the heat transfer medium at a given time in the first and / or the second group and possibly other groups at the same time heated while the ability of the respective fuel line collectors to receive solar radiation power are used at this time.

In a preferred embodiment, heat transfer medium passes through the first group and the second group in succession. This allows a given amount of the heat transfer medium in each of these groups will absorb thermal energy according to the respective capability of the group to absorb energy. In this case, either the first group or the second group can be run through first.

In a further preferred embodiment, heat transfer medium passes through the first and the second group in parallel. As a result, one of their respective ability to absorb energy adapted amount of heat transfer medium can be passed through these groups.

In particular, it is advantageous if the mass flow densities of the at least two partial flows are adjusted in time as a function of the position of the sun. As a result, the varying amounts of solar energy that can be absorbed by the fuel line collector groups in the course of the times of the day, such as the seasons, can be taken into account when determining the quantities of the heat transfer medium conducted through them.

Preferably, the at least two partial streams are generated by a distribution device. This allows their relative size to be regulated easily.

In particular, the at least two partial flows are collected after passing through the respective fuel line collectors by a collection device to a total flow. As a result, it is possible to work with the overall flow instead of the partial flows in the further process control.

In a preferred embodiment, at least one tower receiver and at least one heliostat associated with the corresponding tower receiver are provided, and the heat transfer medium is supplied to the at least one tower receiver after passing through the focal line collectors. As a result, these two components of the power plant can each assume a task corresponding to their specific advantages in the absorption of solar energy.

Advantageously, the heat transfer medium is vaporized in the fuel line collectors and overheated in the at least one tower receiver. As a result, on the one hand the stresses of the fuel line collectors are limited by high pressure and high temperatures, on the other hand, the more expensive tower receiver can be relatively small dimensions.

Further advantages of the method according to the invention have already been explained in connection with the solar thermal power plant according to the invention.

Further advantageous embodiments have also already been explained in connection with the device according to the invention.

The following description of preferred embodiments is used in conjunction with the drawings for a more detailed explanation of the invention. Show it:

1 a first embodiment of a solar thermal power plant according to the invention in a schematic block diagram representation;

2 Examples of the course of each producible power of the following devices for receiving solar energy as a function of the time of day: a) a tower receiver with associated heliostats; b) a group of parabolic trough collectors oriented with their longitudinal direction in north-south direction; c) a group of parabolic trough collectors aligned with their longitudinal direction in west-east direction; each shown for summer and winter under the sunshine conditions of southern Seville;

3 A second embodiment of a solar thermal power plant according to the invention in a schematic block diagram representation.

A first embodiment of a solar thermal power plant according to the invention, which in 1 shown in schematic block diagram representation and there with 10 is designated comprises a focal line collector section 12 in which a liquid heat transfer medium is vaporized, a Turmreceiverabschnitt 14 , in which vaporous heat transfer medium can be overheated, and a turbine section 16 , in which superheated heat transfer medium for generating electrical energy can be used.

The focal line collector section 12 includes a distribution device 18 , a first focal line collector field 20 with first groups 28a . 28b . 28c of fuel line collectors 30 , a second focal line collector field 22 with second groups 32a . 32b . 32c of fuel line collectors 34 , a collection device 24 and a container 26 , The fuel line collectors 30 . 34 each group 28a . 28b . 28c . 32a . 32b . 32c are connected in series with respect to a guide direction of the heat transfer medium and have the same geographical orientation of their longitudinal direction. Exemplary are in 1 seven refueling collectors each 30 . 34 in each group 28a . 28b . 28c . 32a . 32b . 32c shown.

The fuel line collectors 30 the first groups 28a . 28b . 28c have a different geographical orientation in their longitudinal direction than the Focal line collectors 34 the second groups 32a . 32b . 32c , The former are oriented in north-south direction, the latter in west-east direction. The groups 28a . 28b . 28c . 32a . 32b . 32c are connected in parallel with respect to the guide direction of the heat transfer medium.

A focal line collector field 20 . 22 For example, you can have more than 50 groups 28a . 28b . 28c . 32a . 32b . 32c include.

Through the fuel line collectors 30 . 34 Solar radiation is bundled into a focus area. This focus area is linear and has an extension length in the longitudinal direction and an extension width transverse to the longitudinal direction, wherein the extension length is greater than the extension width.

The fuel line collectors 30 . 34 are in particular designed as parabolic trough collectors or linear Fresnel collectors.

The distribution device 18 has an entrance 36 , a number of first outputs 38a . 38b . 38c that is the number of first groups 28a . 28b . 28c corresponds, and a number of second outputs 40a . 40b . 40c that is the number of second groups 32a . 32b . 32c corresponds, on. The entrance 36 the distribution device 18 is with a supply line 42 connected with a pump 44 is provided. Every first exit 38a . 38b . 38c is at a first group 28a . 28b . 28c of the focal line collector field 20 coupled. Every second exit 40a . 40b . 40c is to a second group 32a . 32b . 32c of the focal line collector field 22 coupled.

From the supply line 42 supplied liquid heat transfer medium with a section guide direction 46 is in the distribution device 18 into first partial streams 48a . 48b . 48c whose number is the number of first groups 28a . 28b . 28c corresponds, and second part streams 50a . 50b . 50c whose number is the number of second groups 32a . 32b . 32c corresponds, divisible. The first partial flows 48a . 48b . 48c are about the first outputs 38a . 38b . 38c into the first groups 28a . 28b . 28c of the focal line collector field 20 conductive and have a section guide direction there 52 on. The second partial streams 50a . 50b . 50c are over the second outputs 40a . 40b . 40c into the second groups 32a . 32b . 32c of the focal line collector field 22 conductive and have a section guide direction there 54 on.

In the groups 28a . 28b . 28c . 32a . 32b . 32c is liquid heat transfer medium through from the fuel line collectors 30 and 34 concentrated solar radiation at least partially vaporizable.

The collection device 24 has a first entrance 56 , a second entrance 58 and an exit 60 on. The first groups 28a . 28b . 28c lead into a line 62 that with the first entrance 56 the collection device 24 is connected and over which the first partial flows 48a . 48b . 48c into the collection device 24 are transferable. The second groups 32a . 32b . 32c lead into a line 64 that with the second entrance 58 the collection device 24 is connected and about the second part streams 50a . 50b . 50c into the collection device 24 are transferable, so that the heat transfer medium of the partial streams 48a . 48b . 48c . 50a . 50b . 50c in the collection device 24 to a total flow 66 is collectable.

From the exit 60 the collection device 24 leads a line 68 to an entrance 70 of the container 26 , The container 26 also has a first exit 72 and a second exit 74 on. The first exit 72 is with a lead 76 connected with a pump 78 is provided and to one in the supply line 42 arranged merge 80 leads. The one with a section guide direction 82 in the container 26 guided total current 66 may contain a mixture of liquid and vaporized heat transfer medium. The administration 76 , the pump 78 and the merge 80 form a recirculation device 83 through which in the container 26 from the total stream 66 separated liquid heat transfer medium with a section guide direction 84 back into the supply line 42 and thus back into the focal line collector section 12 can be transferred.

The tower receiver section 14 of in 1 illustrated power plant 10 includes a tower receiver 86 and a heliostat field 88 with a plurality of heliostats 90 of which in 1 schematically four are shown. The tower receiver 86 has a focus area 92 on, in the heliostats 90 Solar radiation is bundled. About one with the second exit 74 of the container 26 connected line 94 is vaporized heat transfer medium with a section guide direction 96 through the focus area 92 conductive and overheatable.

The turbine section 16 of the power plant 10 includes a turbine 98 with a generator 100 and a capacitor 102 , In the tower receiver 86 superheated heat transfer medium is the turbine 98 over a line 104 be supplied, where a portion of its heat energy can be used to generate electrical energy. Through the turbine 98 Guided heat transfer medium is via a line 106 the capacitor 102 supplied, in which further heat energy from the heat transfer medium can be discharged. The capacitor 102 is with the feed pipe 42 connected so that in the power plant 10 a closed heat transfer medium circuit is present.

The method according to the invention for operating a solar thermal power plant according to the invention functions as follows:
Via the supply line 42 becomes liquid heat transfer medium in the fuel line collector section 12 directed. It gets into the distribution device 18 transferred and there in first part streams 48a . 48b . 48c and second part streams 50a . 50b . 50c divided.

The first partial flows 48a . 48b . 48c become the first groups 28a . 28b . 28c of the focal line collector field 20 where it has a north-south oriented portion guide direction 52 exhibit.

The second partial streams 50a . 50b . 50c become the second groups 32a . 32b . 32c of the focal line collector field 22 where it has a section oriented in the west-east direction 54 exhibit.

The partial flows 48a . 48b . 48c . 50a . 50b . 50c take while passing through the respective Brennlinienkollektorfeldes 20 . 22 Heat energy from solar radiation on them from the fuel line collectors 30 and 34 bundled is supplied. The energy supply causes at least partial evaporation of the heat transfer medium. The amount of energy absorbed depends on the orientation of the longitudinal direction of the fuel line collectors 30 and 34 in north-south direction or in west-east direction.

After passing through the focal line collector fields 20 . 22 becomes the heat transfer medium of the partial flows 48a . 48b . 48c . 50a . 50b . 50c in the collection device 24 to a total flow 66 collected, with a section guide direction 82 in the container 26 is directed. A liquid present here part of the heat transfer medium can in a recirculation in containers 26 separated and in the recirculation device 83 over the line 74 back to the distribution device 18 leading supply line 42 be fed. By such a method, the dependence of the groups 28a . 28b . 28c . 32a . 32b . 32c reduced amount of vapor from variations in solar irradiation conditions.

The heat transfer medium in vapor form enters the tower receiver section 14 of the power plant 10 guided. It goes through the focus area 92 of the tower receiver 86 and absorbs heat energy from solar radiation from the heliostats 90 in the focus area 92 is bundled. As a result, the heat transfer medium is overheated.

After passing through the tower receiver section 14 is the heat transfer medium in the turbine section 16 directed. In the turbine 98 By steam release, heat energy is released by the generator 100 can be converted into electrical energy.

Subsequently, the heat transfer medium when passing through the capacitor 102 withdrawn further heat energy. Then it is again in the supply line 42 fed. Thus, the heat transfer medium circuit is closed.

Thus, in the operation of a solar thermal power plant according to the invention by the described inventive method liquid heat transfer medium first partial flows 48a . 48b . 48c in fuel line collectors 30 vaporized with aligned in the north-south direction longitudinal direction and liquid heat transfer medium second streams 50a . 50b . 50c in fuel line collectors 34 vaporized with aligned in the west-east direction longitudinal direction. The following are the first partial flows 48a . 48b . 48c and the second part streams 50a . 50b . 50c to a total flow 66 collected in a tower receiver 86 is overheated.

In such a method, a larger proportion of the total solar energy that can be absorbed by the various components of the solar thermal power plant can be used than in a method in which all the fuel line collectors have the same orientation of their longitudinal direction. Furthermore, the time course of the power generated in the solar thermal power plant is stabilized.

The advantages of the solar thermal power plant according to the invention result from the course of the respective producible power of the components in which a heating of heat transfer medium by solar radiation occurs, depending on the time of day during the summer and during the winter. These courses are in 2 Assuming the solar irradiation conditions of the southern Spanish Seville in each case for a tower receiver with associated heliostats, a group of aligned with their longitudinal direction in north-south direction parabolic trough collectors and a group of oriented with their longitudinal direction in the west-east direction parabolic trough collectors.

A tower receiver with associated heliostats can record most of the solar energy at lunchtime. This applies to the summer during a course 212 as for the winter in a course 214 , wherein the producible power in winter over the throughout the day is lower. If a tower receiver is to be used for overheating of heat transfer medium, which has already been evaporated in other components of a solar thermal power plant, it is advantageous if these other components also absorb most of the solar energy in the summer and in the winter around noon and thus at this time also provide the largest amount of vaporized heat transfer medium available.

A group of parabolic trough collectors aligned with their longitudinal direction in north-south direction shows a course in summer 218 the output that is consistently high from midmorning through noon to the afternoon. The history 220 in winter has two maxima with relatively low values in the morning and afternoon. At lunchtime hardly any solar energy can be absorbed.

In a solar thermal power plant, only such a group of parabolic trough collectors oriented with their longitudinal direction in the north-south direction can be used to vaporize heat transfer medium, which is then transferred to a tower receiver for overheating. In this case, depending on the relative sizing of the two devices, the group provides either significantly more or significantly less vaporized heat transfer medium during most of a winter day than can be overheated by the tower receiver at any one time.

Even in the event that heat transfer medium in a group of aligned with their longitudinal direction in the north-south direction parabolic trough collectors both vaporized and overheated, and then be used to generate electricity in a turbine, resulting in steam surplus and / or steam deficits, as the Turbine must be supplied as constantly as possible with superheated steam.

The history 224 the power generated in the summer of a group of parabolic trough collectors oriented with their longitudinal direction in the west-east direction likewise has a maximum around noon. In the morning and afternoon, however, the values are low, so that on average less solar energy can be absorbed over the entire course of the day than from a group of parabolic trough collectors oriented with their longitudinal direction in the north-south direction. On the other hand, the course is 226 the group of aligned with their longitudinal direction in west-east direction parabolic trough collectors in the winter over the course 224 barely changed in summer, with only slightly lower values throughout the day.

In a solar thermal power plant according to the invention are the two focal line collector groups whose power profiles in 2 are shown, based on a guide direction of the heat transfer medium together before. Depending on the time of day and the season, the heat transfer medium can be successively divided into two groups, in only one of the two groups or in both groups in parallel, divided into sub-streams in any proportions, evaporated and possibly also superheated. Subsequently, it can be routed to a tower receiver or to a steam turbine. This allows a more even over the changes of the times of the day and the seasons performance of the power plant and over the course of a year, a higher efficiency than the operation of a solar thermal power plant in which all fuel line collectors have the same orientation of their longitudinal direction.

In a solar thermal power plant according to the invention, it is possible, for example, to respond to the seasonal fluctuations in solar radiation by virtue of the proportion of heat transfer medium which has been conducted through the group of focal line collectors aligned with its longitudinal direction in the west-east direction at the tower receiver or the steam turbine total amount of heat transfer medium in winter compared to the summer is significantly increased.

A proportion of the group of aligned with their longitudinal direction in the north-south direction Brennlinienkollektoren and the group of aligned with their longitudinal direction in east-west direction Brennlinienkollektoren of 50% of the total number of Brennlinienkollektoren has been in model calculations for operating a power plant according to the invention Sevillian Seville proved to be preferred.

In 3 is a second with 310 designated embodiment of a solar thermal power plant according to the invention shown.

The solar thermal power plant 310 again comprises, in the order defined by a guide direction of a heat transfer medium, a focal line collector section 312 , a tower receiver section 314 and a turbine section 316 ,

The focal line collector section 312 includes a distribution device 318 , a first focal line collector field 320 with a first group 328 of fuel line collectors 330 , a second focal line collector field 322 with a second group 332 of fuel line collectors 334 and a collection device 324 ,

Exemplary are in each focal line collector group 328 . 332 six fuel line collectors 330 . 334 illustrated, which are connected in series with respect to the guide direction of the heat transfer medium and have the same geographical orientation of their longitudinal direction.

The fuel line collectors 330 the first group 328 are aligned with their longitudinal direction in north-south direction, the fuel line collectors 334 the second group 332 in west-east direction.

The first group 328 and the second group 332 are arranged parallel with respect to the guide direction of the heat transfer medium.

The distribution device 318 has one with a supply line 342 connected input 336 , a first exit 338 and a second exit 340 on. About the first exit 338 is a first partial flow 348 the heat transfer medium via a line 349 in the fuel line collector field 320 feasible, via the second exit 340 a second partial flow 350 over a line 351 in the fuel line collector field 322 ,

In the focal line collector fields 320 . 322 is the respective partial flow 348 . 350 into the respective group 328 . 332 be conducted. There, heat transfer medium can be at least partially evaporated. After passing through the respective group 328 . 332 can it in a respective water separator 412 . 414 be directed. Liquid present heat transfer medium is separable here and via a respective line 416 . 418 with one pump each 420 . 422 to one in each group 328 . 332 in front of the first fuel line collector 330 . 334 arranged merge 424 . 426 feasible. In such recirculation devices 425 . 427 , as for example from the German patent DE 101 52 968 C1 are known, in contrast to the recirculation device shown in the first embodiment, each by a group 328 . 332 guided heat transfer medium recirculated.

About a line 362 is vaporized heat transfer medium of the first partial flow 348 of water separator 412 to a first entrance 356 the collection device 324 conductive, and via a wire 364 is vaporized heat transfer medium of the second partial flow 350 of water separator 414 a second entrance 358 the collection device 324 fed. In the collection device 324 is vaporized heat transfer medium of the two partial streams 348 . 350 to a total flow 366 collectable.

The tower receiver section 314 The power plant includes a tower receiver 386 and one in 2 unillustrated heliostat field. The tower receiver 386 has a focus area 392 and an injection device 428 on. Heat transfer medium is from an outlet 360 the collection device 324 over a line 361 in this order through the focus area 392 , through the injector 428 and again through the focus area 392 be conducted. When going through the focus area 392 is it overheatable?

The turbine section 316 of the power plant comprises a turbine distribution device 430 , three with a generator 400 provided turbines 398a . 398b . 398c , a capacitor 402 , a first heat storage 432 , a second heat storage 434 and a container 436 , Furthermore, the turbine section comprises 316 an injection distribution device 458 and a storage distribution device 460 ,

The turbine distribution device 430 has an entrance 438 , a first exit 440 and a second exit 442 on. In the tower receiver 386 superheated heat transfer medium is through the entrance 438 into the turbine distribution device 430 be conducted.

Through the first exit 440 can it in this order over a line 444 with a shut-off device 446 in the first turbine 398a , via a wire 448 from the first turbine 398a in the second turbine 398b and over a line 450 from the second turbine 398b in the third turbine 398c be guided. From the third turbine 398c leaked heat transfer medium is to the condenser 402 be conducted. With the help of a pump 452 is it next from the condenser 402 to the container 436 feasible.

The between the second turbine 398b and the third turbine 398c running line 450 is via a branching device 454 with one to the container 436 leading line 455 connected. Through the line 455 can the container 436 Are supplied heat transfer medium, which has more heat energy than that from the condenser 402 supplied.

Through the second exit 442 the turbine distribution device 430 can overheated heat transfer medium via a pipe 457 in this order through the first heat storage 432 , the second heat storage 434 and a heat exchanger 456 in the container 436 be guided. In the heat stores 432 . 434 each heat energy from the heat transfer medium is dissipated. Advantageously, the first heat storage 432 a solid storage, the second heat storage 434 a latent heat storage.

The injection distribution device 458 has an entrance 462 , a first exit 464 and a second exit 466 on. Liquid heat transfer medium is through one with a pump 468 provided wire 467 from the container 436 over the heat exchanger 456 to the entrance 462 be conducted. In the heat exchanger 456 can be current with the current of the second heat storage 434 to the container 436 Crossed guided heat transfer medium.

By one with a pump 470 provided wire 471 can heat transfer medium from the first output 464 the injection distribution device 458 to the injection device 428 of the tower receiver 386 be transferred. When the from the collection device 324 in the tower receiver 386 transferred amount of heat transfer medium is not large enough to those of the tower receiver 386 Using solar-powered solar energy to overheat it can be done by using the injector 428 be supplied additional heat transfer medium.

The storage distribution device 460 has an entrance 472 , a first exit 474 and a second exit 476 on. From the second exit 466 the injection distribution device 458 can heat transfer medium via a pipe 473 to the entrance 472 the storage distribution device 460 be guided.

From the first exit 474 the storage distribution device 460 is liquid heat transfer medium of the supply line 342 and thus again the fuel line collector section 312 of the power plant 310 fed. This again is a closed heat transfer medium circuit.

From the second exit 476 the storage distribution device 460 is liquid heat transfer medium via a pipe 478 the second heat storage 434 fed. If this is, for example, a latent heat storage, the heat transfer medium can be at least partially evaporated in it. Subsequently, it is in a water separator 480 transferable. In the water separator 480 separated liquid heat transfer medium can by means of a pump 482 one in the line 478 arranged merge 484 be supplied, so that it is the second heat storage 434 can go through again.

Evaporated heat transfer medium is from the water separator 480 over a line 483 through the first heat storage 432 be conducted. For example, if this is a solid reservoir, it can overheat there. Below it can be over a shut-off device 486 to one in between the first turbine 398a and the second turbine 398b running line 448 arranged merge 488 be guided. In this way can in the in the heat storage 432 . 434 stored heat energy for operation of the turbines 398 used when at the time from the tower receiver 386 available amount of superheated steam is insufficient.

Claims (32)

Solar thermal power plant comprising a plurality of fuel line collectors ( 30 ; 34 ; 330 ; 334 ) each having an extension in a longitudinal direction, to which a heat transfer medium can be heated, characterized in that at least one first group ( 28a ; 28b ; 28c ; 328 ) of fuel line collectors ( 30 ; 330 ) and a second group ( 32a ; 32b ; 32c ; 332 ) of fuel line collectors ( 34 ; 334 ) are provided, wherein the fuel line collectors ( 30 ; 34 ; 330 ; 334 ) of each group ( 28a ; 28b ; 28c ; 32a ; 32b ; 32c ; 328 ; 332 ) are connected in series with respect to a guide direction of the heat transfer medium and have the same geographical orientation of their longitudinal direction, and that the fuel line collectors ( 30 ; 330 ) of the first group ( 28a ; 28b ; 28c ; 328 ) have a different longitudinal orientation than the focal line collectors ( 34 ; 334 ) of the second group ( 32a ; 32b ; 32c ; 332 ). Solar thermal power plant according to claim 1, characterized in that the first group ( 28a ; 28b ; 28c ; 328 ) and the second group ( 32a ; 32b ; 32c ; 332 ) are connected in parallel with respect to the guide direction of the heat transfer medium. Solar thermal power plant according to claim 1, characterized in that the first group ( 28a ; 28b ; 28c ; 328 ) and the second group ( 32a ; 32b ; 32c ; 332 ) are connected in series with respect to the guide direction of the heat transfer medium. Solar thermal power plant according to one of the preceding claims, characterized by a distribution device ( 18 ; 318 ), through which at least two partial streams ( 48 ; 50 ; 348 ; 350 ) of the heat transfer medium for at least one group ( 28a ; 28b ; 28c ; 32a ; 32b ; 32c ; 328 ; 332 ) are producible. Solar thermal power plant according to claim 4, characterized by a collecting device ( 24 ; 324 ) through which the at least two partial streams ( 48 ; 50 ; 348 ; 350 ) to a total flow ( 66 ; 366 ) are collectable. Solar thermal power plant according to claim 5, characterized in that the collecting device ( 24 ; 324 ) based on the guide direction of the heat transfer medium the fuel line collectors ( 30 ; 34 ; 330 ; 334 ) is connected downstream. Solar thermal power plant according to one of the preceding claims, characterized by at least one recirculation device ( 83 ; 425 ; 427 ) containing one or more groups ( 28a ; 28b ; 28c ; 32a ; 32b ; 32c ; 328 ; 332 ) assigned. Solar thermal power plant according to one of the preceding claims, characterized in that the geographic orientation of the longitudinal direction and / or the number of fuel line collectors ( 30 ; 34 ; 330 ; 334 ) of the groups ( 28a ; 28b ; 28c ; 32a ; 32b ; 32c ; 328 ; 332 ) depends on the geographical location of the location of the solar thermal power plant. Solar thermal power plant according to one of the preceding claims, characterized in that a focal line collector ( 30 ; 34 ; 330 ; 334 ) each having a focus area with an extension length in the longitudinal direction and an extension width transverse to the longitudinal direction, wherein the extension length is greater than the extension width. Solar thermal power plant according to one of the preceding claims, characterized in that at least one focal line collector ( 30 ; 34 ; 330 ; 334 ) is designed as a parabolic trough collector. Solar thermal power plant according to one of the preceding claims, characterized in that at least one focal line collector ( 30 ; 34 ; 330 ; 334 ) is designed as a linear Fresnel collector. Solar thermal power plant according to one of the preceding claims, characterized by at least one tower receiver ( 86 ; 386 ) and at least one corresponding tower receiver ( 86 ; 386 ) associated heliostats ( 90 ), wherein the heat transfer medium at the fuel line collectors ( 30 ; 34 ; 330 ; 334 ) and subsequently to the at least one tower receiver ( 86 ; 386 ) is heated. Solar thermal power plant according to claim 12, characterized in that the at least one tower receiver ( 86 ; 386 ) based on the guide direction of the heat transfer medium, a collection device ( 24 ; 324 ) is connected upstream. Solar thermal power plant according to claim 12 or 13, characterized in that the at least one tower receiver ( 86 ; 386 ) an injection device ( 428 ) is assigned for liquid heat transfer medium. Solar thermal power plant according to one of the preceding claims, characterized in that the fuel line collectors ( 30 ; 330 ) of the first group ( 28a ; 28b ; 28c ; 328 ) are aligned with their longitudinal direction in the north-south direction and the fuel line collectors ( 34 ; 334 ) of the second group ( 32a ; 32b ; 32c ; 332 ) are aligned with their longitudinal direction in the west-east direction. Solar thermal power plant according to one of the preceding claims, characterized in that the ratio of the number of fuel line collectors ( 30 ; 330 ) of the first group ( 28a ; 28b ; 28c ; 328 ) and / or the second group ( 32a ; 32b ; 32c ; 332 ) to the total number of fuel line collectors ( 30 ; 34 ; 330 ; 334 ) ranges between 20% and 80%. Solar thermal power plant according to claim 16, characterized in that the ratio is in the range between 40% and 60%. Solar thermal power plant according to one of the preceding claims, characterized by a device for generating electrical energy, which at least one steam turbine ( 98 ; 398 ) and at least one generator ( 100 ; 400 ), wherein the at least one steam turbine ( 98 ; 398 ) based on the guide direction of the heat transfer medium the fuel line collectors ( 30 ; 34 ; 330 ; 334 ) is connected downstream. Solar thermal power plant according to claim 18, characterized in that the at least one steam turbine ( 98 ; 398 ) based on the direction of the heat transfer medium one or more tower receivers ( 86 ; 386 ) is connected downstream. Solar thermal power plant according to one of the preceding claims, characterized by an additional heating device. Solar thermal power plant according to claim 20, characterized in that the additional heating device comprises a fossil burner device. Solar thermal power plant according to one of the preceding claims, characterized by at least one heat storage ( 432 ; 434 ). Solar thermal power plant according to claim 22, characterized in that the at least one heat storage ( 432 ; 434 ) via a heat transfer medium circuit with at least one steam turbine ( 98 ; 398 ) is coupled. Solar thermal power plant according to one of the preceding claims, characterized in that water is used as the heat transfer medium. A method for operating a solar thermal power plant comprising a plurality of fuel line collectors each having an extension in a longitudinal direction, wherein at least a first group of fuel line collectors and a second group of fuel line collectors are provided, the fuel line collectors of each group connected in series with respect to a guide direction of a heat transfer medium are and have the same geographical orientation of their longitudinal direction, and the focal line collectors of the first group have a different geographical orientation of their longitudinal direction than the focal line collectors of the second group, in which the heat transfer medium is supplied to the at least two groups of fuel line collectors. A method according to claim 25, characterized in that heat transfer medium passes through the first group and the second group successively. A method according to claim 25, characterized in that heat transfer medium passes through the first group and the second group in parallel. A method according to claim 27, characterized in that the mass flow densities of the at least two partial streams are adjusted in time as a function of the position of the sun. A method according to claim 27 or 28, characterized in that the at least two partial streams are generated by a distribution device. Method according to one of claims 27 to 29, characterized in that the at least two partial flows are collected after passing through the respective fuel line collectors by a collection device to a total flow. Method according to one of claims 25 to 30, characterized in that the solar thermal power plant comprises at least one tower receiver and at least one associated with the corresponding tower receiver heliostats and that the heat transfer medium is fed to the at least one tower receiver after passing through the fuel line collectors. A method according to claim 31, characterized in that the heat transfer medium in the fuel line collectors is evaporated and overheated in the at least one tower receiver.

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