阅读说明：本技术 一种中深层地热能耦合太阳能的零排放供热系统 (Zero-emission heating system with middle-deep geothermal energy coupled with solar energy ) 是由 王贵玲 刘彦广 张薇 秦祥熙 石磊 于 2021-11-23 设计创作，主要内容包括：本发明涉及一种中深层地热能耦合太阳能的零排放供热系统。它解决了现有技术设计不够合理等技术问题。包括产能单元、储能单元以及用能单元,产能单元具有中深层地埋管换热装置、太阳能光热集热装置以及光伏发电系统,储能单元具有电储热锅炉,中深层地埋管换热装置通过中深层地热热泵与电储热锅炉和/或用能单元相连,太阳能光热集热装置与电储热锅炉和/或用能单元相连,光伏发电系统连接有储电设备,储电设备与电储热锅炉、中深层地热热泵以及用能单元相连。优点在于：实现复合高效的供热蓄热系统,同时通过超低能耗集中供热和获取可在生清洁电力,实现了北方集中供热整套系统的零排放。(The invention relates to a zero-emission heating system with middle-deep geothermal energy coupled with solar energy. It has solved prior art design technical problem such as reasonable inadequately. The solar energy and heat collection device is connected with the electric heat storage boiler and/or the energy utilization unit, the photovoltaic power generation system is connected with an electricity storage device, and the electricity storage device is connected with the geothermal heat storage boiler, the middle-deep buried pipe heat exchange device and the energy utilization unit. Has the advantages that: the system realizes a composite efficient heat supply and heat storage system, simultaneously realizes the zero emission of the whole system of the northern central heat supply by the ultra-low energy consumption central heat supply and the acquisition of clean electric power which can be generated in situ.)

1. A zero-emission heating system with middle-deep geothermal energy coupled with solar energy comprises a power generation unit (1), an energy storage unit (2) and an energy utilization unit (3), and is characterized in that the power generation unit (1) is provided with a middle-deep buried pipe heat exchange device (11), a solar photo-thermal heat collection device (12) and a photovoltaic power generation system (13), the energy storage unit (2) is provided with an electric heat storage boiler (21) connected with the energy utilization unit (3), the middle-deep buried pipe heat exchange device (11) is directly connected with the electric heat storage boiler (21), or the middle-deep buried pipe heat exchange device (11) is connected with the electric heat storage boiler (21) and/or the energy utilization unit (3) through a middle-deep geothermal heat pump (22), and the solar photo-thermal heat collection device (12) is connected with the electric heat storage boiler (21) and/or the energy utilization unit (3), the photovoltaic power generation system (13) is connected with an electricity storage device (23), and the electricity storage device (23) is connected with at least one of the electric heat storage boiler (21), the middle-deep geothermal heat pump (22) and the energy utilization unit (3).

2. The system for zero emission heating of the coupling of geothermal energy to solar energy in the medium and deep layers according to claim 1, wherein the energy utilization unit (3) comprises any one or a combination of a building terminal heating radiant floor (31) with a building wall capillary radiant system (32) and an electric floor heating device (33) with a building wall capillary radiant system (32).

3. The system according to claim 2, wherein the electric heat storage boiler (21) is disposed on a heat supply load side pipeline (24), one end of the heat supply load side pipeline (24) is connected in parallel with the buried pipe heat exchanger (11) and the solar thermal heat collector (12), the other end is connected to a building terminal heating radiant floor (31) of the energy utilization unit (3), and the geothermal heat pump (22) is connected to the heat supply load side pipeline (24).

4. The system according to claim 3, wherein the pipeline (24) on the heating load side is provided with a first-stage load-side water pump (25) on one side of the electric heat storage boiler (21) and a second-stage load-side water pump (26) on the other side of the electric heat storage boiler (21), and the first-stage load-side water pump (25) is connected with the second-stage load-side water pump (26) through the electric heat storage boiler (21) or the first-stage load-side water pump (25) is directly connected with the second-stage load-side water pump (26).

5. The system according to claim 3 or 4, wherein the heat exchanger (11) comprises a plurality of sequentially arranged closed circulation wells (111), and the closed circulation wells (111) are connected to the heat load side pipeline (24) through the well circulation water pump (112).

6. A system for zero-emission heating by coupling geothermal energy to solar energy in a medium-deep layer according to claim 5, characterised in that at least one of the closed circulation wells (111) in a medium-deep layer is directly connected to the capillary radiant system (32) of the building wall of the energy unit (3) by means of a bypass line (113).

7. The system according to claim 3, wherein the solar photo-thermal collector (12) comprises a solar photo-thermal collector (121), the solar photo-thermal collector (121) is connected to a heat storage tank (123) through a heat collection circulating water pump (122), and the heat storage tank (123) is connected to the heat supply load side pipeline (24).

8. The system according to claim 5, wherein the electricity storage device (23) is connected with an electric heat storage boiler (21), a middle-deep geothermal heat pump (22), an electric floor heating device (33) of the energy utilization unit (3) and a middle-deep well circulating water pump (112) respectively.

9. The system according to claim 6, wherein the middle-deep closed circulation well (111) connected to the capillary radiant system (32) of the building wall is connected to the capillary radiant system (32) of the building wall through a first valve (114) and connected to the heat load side pipe (24) through a second valve (115), and the water supply pipe (241) of the heat load side pipe (24) is provided with a third valve (116) between the two water inlet ends of the middle-deep geothermal heat pump (22), and the water return pipe (242) of the heat load side pipe (24) is provided with a fourth valve (117) between the two water return ends of the middle-deep geothermal heat pump (22).

10. The system according to claim 9, wherein the building wall capillary radiation system (32) comprises a wall (323) disposed between an inner wall plastering (321) and an outer wall plastering (322), the capillary system plate (324) is disposed on a side of the wall (323) near the outer wall plastering (322), the capillary system plate (324) comprises a fixed grid (325) disposed on a side of the wall (323), a capillary network (326) is fixed on the fixed grid (325), the capillary network (326) is distributed on a side of the wall (323) and water inlets and water outlets of the capillary network (326) are respectively connected to the middle-deep closed circulation well (111).

Technical Field

The invention belongs to the technical field of renewable energy devices, and particularly relates to a zero-emission heating system with middle-deep geothermal energy coupled with solar energy.

Background

The technology of the middle-deep geothermal closed type circulating ground source heat pump is characterized in that hot water which is circulated out by a heat exchanger in a middle-deep geothermal well and geothermal heat exchange is used as a heat source to enter a high-temperature heat pump unit evaporator, and the water supply temperature required by building heating is achieved through the lifting of the high-temperature heat pump unit, so that the building is stably heated.

The solar heat collection technology is mainly a technology for converting direct radiation and scattered radiation in solar radiation into medium-low temperature hot water through photo-thermal conversion, collecting and transmitting the medium-low temperature hot water to a heat using terminal, and most of the solar heat collection technology adopts a non-light-gathering heat collection technology for hot water or heating of community residents. The solar photovoltaic power generation technology is a technology for directly converting solar light energy into electric energy. However, the intensity of solar energy is influenced by factors such as season, place and climate, and is an unstable energy form, and an auxiliary heat and electricity storage technology is generally needed.

The heat storage technology is an energy technology which stores heat energy through a phase change energy storage material or stores heat energy prepared by solar energy through an underground rock-soil body and is used for peak regulation heating requirements, so that the cost is reduced.

At present, there is also a complementary technical system form formed by integrating the intermediate-deep geothermal heat and the solar heat collecting device, for example, chinese patent document discloses a cold-heat combined supply system of intermediate-deep geothermal heat and light-heat coupling [ application number: 201811202979.5]: the combined cooling and heating system comprises: the geothermal heat taking device is used for extracting heat of underground rocks; the photothermal heat supplementing device is used for supplementing heat when the heat extracted by the geothermal heat extracting device from underground rocks is insufficient; the heating system exchanges heat with the geothermal heat taking device and is used for supplying heat to users; a cooling system exchanging heat with the geothermal heat-taking device for cooling a user.

The scheme only uses solar energy as a supplementary heat source for heat supply, organic combination of heat supply and heat storage cannot be realized, unstable solar energy cannot be coupled with middle-deep geothermal energy through converting stable heat energy sources, high-efficiency and energy-saving heat supply is realized, and a middle-deep underground space is not used as a heat storage space, so that high-efficiency heat supply of the middle-deep geothermal energy is realized, geothermal energy is not utilized in a cascade manner, and cascade heat utilization is performed by combining a building maintenance structure.

Disclosure of Invention

The invention aims to solve the problems and provides a zero-emission heating system with middle-deep geothermal energy coupled with solar energy, aiming at realizing a high-efficiency heating and heat storage system combining a middle-deep geothermal closed cycle ground source heat pump system, a solar heat collection and heat supply system, a solar photovoltaic power generation system and a phase change heat storage system, simultaneously realizing zero emission of the whole northern central heating system and realizing the carbon neutralization target in the field of assisted heat supply by carrying out central heat supply with ultralow energy consumption and acquiring clean power which can be generated in situ.

In order to achieve the purpose, the invention adopts the following technical scheme: the energy storage unit is provided with an electric heat storage boiler connected with the energy consumption unit, the middle-deep buried pipe heat exchange device is directly connected with the electric heat storage boiler, or the middle-deep buried pipe heat exchange device is connected with the electric heat storage boiler and/or the energy consumption unit through a middle-deep geothermal heat pump, the solar photo-thermal heat collection device is connected with the electric heat storage boiler and/or the energy consumption unit, the photovoltaic power generation system is connected with an electric storage device, and the electric storage device is connected with at least one of the electric heat storage boiler, the middle-deep geothermal heat pump and the energy consumption unit.

The traditional northern centralized heating is centralized heating through coal-fired cogeneration and carbon emission amplification, and the system realizes high-efficiency heating for northern centralized heating users by fully utilizing middle-deep geothermal energy, solar energy and electric energy through an independent heat supply network system, and simultaneously utilizes phase-change materials and middle-deep underground rock-soil bodies to store solar energy through solar photothermal and photovoltaic electric heating, thereby realizing the regulation and storage combination of the centralized heating.

In the above zero-emission heating system with coupling of the intermediate-deep geothermal energy and the solar energy, the energy utilization unit includes any one or a combination of two of a building terminal heating radiation floor including a building wall capillary radiation system and an electric floor heating device including a building wall capillary radiation system).

In the above zero-emission heating system with coupling of the intermediate-deep geothermal energy and the solar energy, the electric heat storage boiler is arranged on a heating load side pipeline, one end of the heating load side pipeline is respectively connected with the intermediate-deep buried pipe heat exchange device and the solar photo-thermal heat collection device in parallel, the other end of the heating load side pipeline is connected with a building terminal heating radiation floor of the energy utilization unit, and the intermediate-deep geothermal heat pump is connected on the heating load side pipeline.

In the above-mentioned zero release heating system of middle-deep geothermal energy coupling solar energy, heat supply load side pipeline on be equipped with the load side one-level water pump that is located electric heat-retaining boiler one side and the load side second grade water pump that is located electric heat-retaining boiler opposite side, just load side one-level water pump link to each other or load side one-level water pump and load side second grade water pump directly link to each other through electric heat-retaining boiler and load side second grade water pump.

In the above zero-emission heating system with the coupling of the intermediate-deep-layer geothermal energy and the solar energy, the intermediate-deep-layer buried pipe heat exchange device comprises a plurality of intermediate-deep-layer closed circulation wells which are arranged in sequence, and the intermediate-deep-layer closed circulation wells are respectively connected with the heating load side pipeline through intermediate-deep-layer well circulating water pumps.

In the above zero emission heating system with intermediate-deep geothermal energy coupled with solar energy, at least one of the intermediate-deep closed circulation wells is directly connected with the building wall capillary radiation system of the energy utilization unit through a bypass pipeline.

In the above zero-emission heating system with coupling of the intermediate-deep geothermal energy and the solar energy, the solar photo-thermal heat collection device comprises a solar photo-thermal heat collector, the solar photo-thermal heat collector is connected with the heat storage water tank through a heat collection circulating water pump, and the heat storage water tank is connected to a heating load side pipeline.

In the above zero-emission heating system with coupling of the intermediate-deep geothermal energy and the solar energy, the electricity storage device is respectively connected with the electric heat storage boiler, the intermediate-deep geothermal heat pump, the electric ground heating device of the energy utilization unit and the intermediate-deep well circulating water pump.

In the above-mentioned zero emission heating system of middle-deep geothermal energy coupling solar energy, the middle-deep closed circulation well that links to each other with building wall capillary radiation system in the middle-deep closed circulation well links to each other with building wall capillary radiation system through first valve respectively and connects on heat supply load side pipeline through the second valve, and the delivery pipe of heat supply load side pipeline on be equipped with the third valve that is located between two intake ends of middle-deep geothermal heat pump, and the wet return of heat supply load side pipeline on be equipped with the fourth valve that is located between two wet return ends of middle-deep geothermal heat pump.

In the above zero-emission heating system with coupling of the geothermal energy of the middle-deep layer to the solar energy, the capillary radiation system of the building wall comprises a wall body arranged between inner wall plastering and outer wall plastering, a capillary system plate is arranged on one side of the wall body close to the outer wall plastering, the capillary system plate comprises a fixed grid arranged on one side of the wall body, a capillary network is fixed on the fixed grid, the capillary network is distributed on one side of the wall body, and water inlets and water outlets of the capillary network are respectively connected with the closed circulation well of the middle-deep layer.

Compared with the prior art, the invention has the advantages that:

1. can generate energy sources to complement each other: one hundred percent of energy side utilization can be in the living energy, namely solar photovoltaic, solar photothermal and middle-deep geothermal energy are complementary, and through the coupling cascade design of the innovative photothermal geothermal system and the energy for the building, the installed capacity of the solar photovoltaic is reduced, the system configuration is optimized, the initial investment of a zero-emission system is reduced, and the system popularization range is wider.

2. And (3) cross-cycle storage and use combination: except that the phase change boiler heat storage and the solar photovoltaic power storage are adopted for peak regulation during the heating season, the medium-deep rock-soil heat storage technology is innovatively adopted, the heat balance of the medium-deep underground heat exchange is realized, the defect of unstable solar energy is overcome, and the integral operation energy efficiency of the system is high.

3. The gradient utilization of geothermal energy: the middle-deep geothermal heating adopts a middle-deep closed circulating heat pump system, hot water heated and circulated by a heat exchanger in a middle-deep geothermal well is used as a heat source, the problem of recharge is avoided, but the heat exchange capacity is limited, cascade utilization can be performed at the moment for tail end heating, part of 5-15 ℃ water enters a heat pump unit evaporator, the requirement of 45 ℃ water heating of a building floor heating system is met through the lifting of the heat pump unit, and meanwhile, part of 5-15 ℃ water is directly supplied to a wall capillary radiation system, so that the heat insulation performance of a building maintenance structure is improved by using lower temperature water, and part of outdoor cold load is borne.

Drawings

FIG. 1 is a schematic diagram of the system of the present invention;

FIG. 2 is a schematic diagram of the system heating operating condition temperature of the present invention;

FIG. 3 is a schematic structural diagram of a building wall capillary radiation system according to the present invention;

FIG. 4 is a side view of a building wall capillary radiation system of the present invention;

FIG. 5 is a schematic diagram of the temperature of the phase change boiler under the heat storage condition of the present invention;

FIG. 6 is a schematic diagram of the heat storage working condition temperature of the medium-deep rock-soil body according to the invention;

FIG. 7 is a schematic view of a medium snow melting heat supply industrial mine according to the present invention;

in the figure: the energy production unit 1, the middle-deep buried pipe heat exchange device 11, the middle-deep closed circulation well 111, the outer pipe 111a, the inner pipe 111b, the middle-deep well circulating water pump 112, the bypass pipeline 113, the first valve 114, the second valve 115, the third valve 116, the fourth valve 117, the solar photo-thermal heat collection device 12, the solar photo-thermal heat collector 121, the heat collection circulating water pump 122, the heat storage water tank 123, the photovoltaic power generation system 13, the energy storage unit 2 and the electric heat storage boiler 21, the system comprises a middle-deep geothermal heat pump 22, an electric storage device 23, a heat supply load side pipeline 24, a water supply pipe 241, a water return pipe 242, a load side primary water pump 25, a load side secondary water pump 26, an energy using unit 3, a building terminal heating radiation floor 31, a building wall capillary radiation system 32, electric floor heating equipment 33, inner wall plastering 321, outer wall plastering 322, a wall 323, a capillary system plate 324, a fixed grid 325 and a capillary network 326.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.

As shown in fig. 1-2, a zero-emission heating system with middle-deep geothermal energy coupled with solar energy comprises a power generation unit 1, an energy storage unit 2 and an energy utilization unit 3, wherein the power generation unit 1 comprises a middle-deep buried pipe heat exchange device 11, a solar photothermal heat collection device 12 and a photovoltaic power generation system 13, the energy storage unit 2 comprises an electric heat storage boiler 21 connected with the energy utilization unit 3, the middle-deep buried pipe heat exchange device 11 is directly connected with the electric heat storage boiler 21, or the middle-deep buried pipe heat exchange device 11 is connected with the electric heat storage boiler 21 and/or the energy using unit 3 through the middle-deep geothermal heat pump 22, the solar photo-thermal heat collecting device 12 is connected with the electric heat storage boiler 21 and/or the energy utilization unit 3, the photovoltaic power generation system 13 is connected with an electricity storage device 23, and the electricity storage device 23 is connected to at least one of the electric heat storage boiler 21, the intermediate-deep geothermal heat pump 22, and the energy using unit 3. Preferably, the electric storage device 23 is connected with an electric heat storage boiler 21, a middle-deep geothermal heat pump 22, an electric floor heating device 33 of the energy using unit 3 and a middle-deep well circulating water pump 112.

Wherein, energy production unit 1 mainly is through middle-deep geothermal energy, solar energy production heat energy and electric energy, realizes that the energy side hundred percent can be in the application of the renewable energy to realize the zero release heat supply, energy storage unit 2 mainly is through accumulate device 23 and electric heat storage boiler 21 storage thermoelectricity, and through the mode of electrical heating or heat pump, changes the electric energy into heat energy, and include with energy unit 3: the building terminal heating radiation floor 31 is combined with a building wall capillary radiation system 32, or the building wall capillary radiation system 32 is combined with an electric floor heating device 33, or the combination of the three. Mainly comprises equipment for heating and hot water equipment of building terminals. The system efficiently realizes the thermoelectric production of the capacity unit through intelligent control and energy storage regulation, converts the thermoelectric production into the heat energy required by the terminal and realizes the supply and demand balance of an intelligent heat supply network.

Specifically, the electric heat storage boiler 21 is provided on a heat supply load side pipe 24, one end of the heat supply load side pipe 24 is connected in parallel with the intermediate-depth buried pipe heat exchanging device 11 and the solar photo-thermal heat collecting device 12, respectively, and the other end is connected to a building terminal heating radiation floor 31 of the energy using unit 3, and the intermediate-depth geothermal heat pump 22 is connected to the heat supply load side pipe 24.

The heat supply load side pipeline 24 is provided with a load side first-stage water pump 25 located on one side of the electric heat storage boiler 21 and a load side second-stage water pump 26 located on the other side of the electric heat storage boiler 21, and the load side first-stage water pump 25 is connected with the load side second-stage water pump 26 through the electric heat storage boiler 21 or the load side first-stage water pump 25 is directly connected with the load side second-stage water pump 26.

The middle-deep buried pipe heat exchanger 11 in this embodiment includes a plurality of middle-deep closed circulation wells 111 arranged in sequence, and the middle-deep closed circulation wells 111 are connected to the heat supply load side pipeline 24 through middle-deep well circulation water pumps 112, respectively.

Preferably, at least one of the closed circulation wells 111 in the deep layer is directly connected to the building wall capillary radiation system 32 of the energy using unit 3 through a bypass line 113. A part of 5-15 ℃ water in the middle-deep layer closed circulation well 111 directly enters the wall capillary radiation system 32, so that the heat insulation performance of the building maintenance structure is improved by using the water with lower temperature, and part of outdoor cold load is borne.

Further, the solar photo-thermal heat collecting device 12 herein includes a solar photo-thermal heat collector 121, the solar photo-thermal heat collector 121 is connected to a heat storage water tank 123 through a heat collecting circulation water pump 122, and the heat storage water tank 123 is connected to the heat supply load side pipeline 24.

The middle-deep closed circulation well 111 connected to the building wall capillary radiation system 32 in the middle-deep closed circulation well 111 is connected to the building wall capillary radiation system 32 through the first valve 114 and connected to the heat supply load side pipeline 24 through the second valve 115, the water supply pipe 241 of the heat supply load side pipeline 24 is provided with the third valve 116 located between the two water inlet ends of the middle-deep geothermal heat pump 22, and the water return pipe 242 of the heat supply load side pipeline 24 is provided with the fourth valve 117 located between the two water return ends of the middle-deep geothermal heat pump 22.

As shown in fig. 3-4, the building wall capillary radiation system 32 herein comprises a wall 323 arranged between an inner wall plastering 321 and an outer wall plastering 322, the side of the wall 323 adjacent to the outer wall plastering 322 is provided with a capillary system plate 324, the capillary system plate 324 comprises a fixed grating 325 arranged on one side of the wall 323, a capillary network 326 is fixed on the fixed grating 325, the capillary network 326 is distributed on one side of the wall 323, and water inlets and water outlets of the capillary network 326 are respectively connected with the middle-deep closed circulation well 111.

In this embodiment, the working condition of the zero-emission heating system with the intermediate-deep geothermal energy coupled with the solar energy is as follows:

single heat supply working condition:

the heating single heat supply working condition of the middle-deep geothermal heat pump floor is as follows: starting the middle-deep layer closed circulation well 111, starting the middle-deep layer well circulation water pump 112, starting the middle-deep layer geothermal heat pump 22, the heat supply load side first-stage water pump 25 and the load side second-stage water pump 26, and providing hot water with the temperature of 45 ℃ for the building terminal heating radiation floor 31.

The solar photo-thermal system floor heating single heat supply working condition is as follows: the solar photo-thermal collector 121, the heat storage water tank 123 and the heat collection circulating water pump 122 are started to establish solar heat collection circulation, and the heat supply load side first-stage water pump 25 and the load side second-stage water pump 26 are started to provide hot water with the temperature of 45 ℃ for the building terminal heating radiation floor 31.

The electric heat storage boiler floor heating single heat supply working condition is as follows: the electric heating function or the heat storage and release function of the electric heat storage boiler 21 is started, and the second-stage water pump 26 on the load side is started to provide hot water with the temperature of 45 ℃ for the heating radiation floor 31 at the building terminal.

Solar photovoltaic power generation electric heating single heat supply working condition: the photovoltaic power generation system 13 is started, electric power is stored through the power storage device 23 and is directly supplied to the electric floor heating device 33 adopting the floor heating electric heating film in the building terminal room, the ground radiation electric heating mode is achieved, and the electric heating film can be laid in the main moving area as auxiliary heating due to the fact that the tail end of the electric heating device is heated by the middle-deep water floor.

The heat preservation and heat supply working condition of the middle-deep geothermal direct supply wall body is as follows: the middle-deep layer closed circulation well 111 connected with the bypass pipeline 113 is started, the middle-deep layer well circulation water pump 112 is started, the bypass pipeline 113 is directly connected with the building wall capillary radiation system 32, hot water with the temperature of 5-15 ℃ is provided for wall heat radiation, and cold load brought by maintenance of the structure is reduced.

Snow melting and heat supply working conditions:

as shown in fig. 7: the middle-deep closed circulation well 111 is composed of concentric sleeve structure, the outer pipe 111a is fixed in the drilling well of 2000 meters underground by the cement by the petroleum steel pipe, the inner pipe 111b is the high temperature resistant modified PE pipe, the bottom of the inner pipe 111b is the screen pipe, which plays the role of supporting the inner pipe and circulating medium, the circulating water enters from the annular space area of the outer pipe 111a, is pumped to the ground from the bottom of the inner pipe 111b by the water pump, and is connected with the capillary radiation system 32 of the building wall, in the northern area, the temperature of the shallow layer of 100 meters of rock soil is about 10 ℃, the temperature of the middle-deep layer of 2000 meters is at least 60 ℃, so the temperature of the water supply and return of the middle-deep closed circulation well 111 can be as high as 60 ℃ instantly when starting and running after intermittence, which can melt snow fast, and increase the indoor temperature, improve the slow temperature rise characteristic of the radiation system, can run under the working condition of 15 ℃ water supply after stable heat supply, and can also keep the outer wall from being adhered by ice and snow, meanwhile, partial indoor heat load is borne, so that ice and snow on the outer wall of the building in an extremely cold area are prevented from being generated, and the snow can be melted at a lower temperature, so that the indoor heat load requirement is reduced.

Compound heat supply working condition:

as shown in the attached figure 2, according to the load change ratio, the middle-deep-layer buried pipe heat exchange device 11 and the direct supply system are preferentially started to serve as basic heat supply sources, the middle-deep-layer geothermal heat pump 22 single heat supply working condition and the middle-deep-layer geothermal direct supply wall heat preservation and heat supply working condition are operated at the moment, the middle-deep-layer geothermal heat supply heat load cannot meet the peak load, the solar thermal heat collection device 12 is started to carry out combined heat supply, the solar thermal system heat supply working condition is compositely operated at the moment, for extremely cold weather, the electric heat storage boiler 21 is started to carry out electric heating or heat storage and release to carry out heat supply, meanwhile, the electric heating is started, the middle-deep-layer geothermal heat pump composite solar thermal energy and electric heat storage boiler heat supply system heat supply working condition is operated at the moment, and the electric heating single heat supply working condition is assisted. The composite system switches the heat source system according to the optimal heat supply energy efficiency of the system as a control target, so that the energy consumption of the system is reduced, and the stability of the system is improved.

Energy storage working condition:

the heat storage working condition of the phase-change boiler is as follows:

as shown in fig. 5, during intermittent heating in a non-heating season or a heating season, the solar photo-thermal collector 121 and the photovoltaic power generation system 13 may be turned on, the solar photo-thermal collector may produce hot water, and the photovoltaic power generation system may produce hot water by the electric heat storage boiler 21, so that the heat energy converted from solar energy is stored in the boiler phase-change heat storage material.

The heat storage working condition of the medium-deep rock-soil body is as follows:

as shown in fig. 6, during the intermittent heating off period in the non-heating season or the heating season, the solar thermal collector 121 and the photovoltaic power generation system 13 can be opened, the solar thermal collector can prepare hot water, the photovoltaic power generation system can prepare hot water with a temperature higher than 50 ℃ through the electric heat storage boiler 21 for power generation, and simultaneously the middle and deep well circulating water pump 112 is opened to circulate the hot water with a temperature higher than 50 ℃ prepared by the solar thermal photovoltaic in the middle and deep closed circulating well 111, so that solar energy is stored in the underground middle and deep rock mass in a photo-thermal and photo-electric manner, the average temperature of the upper half part of the rock mass is increased, and the heat supply working condition efficiency of the geothermal well is favorably improved. The electric power of a water pump for driving the water system to circulate comes from the solar photovoltaic system, so that the heat storage does not generate energy consumption.

The solar photovoltaic power storage working condition is as follows:

the photovoltaic power generation system 13 is started, and the electric power is stored through the electric power storage device 23, so that the electric power can be stably transmitted to the intermediate-deep geothermal heat pump 22, the electric heat storage boiler 21 and the electric floor heating device 33 when the heat supply network system is required.

The heat stored can be used as a peak-shaving heat source, so that the overall operation energy consumption is further reduced. For a well group of a plurality of medium-deep closed geothermal wells, part of wells can be used as heat storage wells and part of wells can be used as heat supply wells, the wells are flexibly configured during operation, and the overall operation efficiency is improved.

The beneficial effect of this embodiment lies in:

can generate energy sources to complement each other: the solar photovoltaic, solar thermal and middle-deep geothermal energy can be used as the renewable energy sources in hundreds of percent at the energy source side, and the solar photovoltaic installed capacity is reduced, the system configuration is optimized, the initial investment of a zero-emission system is reduced, and the system popularization range is wider through the innovative coupling cascade design of the photo-thermal geothermal system and the building energy.

And (3) cross-cycle storage and use combination: the method is characterized in that phase change boiler heat storage and solar photovoltaic electricity storage are adopted for peak regulation during a heating season, namely, intermediate-deep geothermal energy is fully utilized as a basic heat source, auxiliary solar energy is utilized as a peak regulation measure, meanwhile, solar energy is utilized for storing energy for underground rock-soil bodies and the phase change boiler during a non-heating season or an intermittent heating period of the heating season, a multi-energy complementary system peak regulation and energy storage technology is utilized, the heat exchange capability of an intermediate-deep closed geothermal well is greatly enhanced, an intermediate-deep rock-soil body heat storage technology is innovatively adopted, namely, hot water from solar photovoltaic photo-thermal preparation is reversely stored into the intermediate-deep rock-soil bodies during the non-heating season or the intermittent heating period of the heating season, the average temperature of the rock-soil bodies around an intermediate-deep buried pipe is increased, and the efficiency of intermediate-deep geothermal heat pump heat supply and direct heat supply working conditions is greatly improved. The heat balance of the underground heat exchange of the middle-deep layer is realized, the defect of unstable solar energy is overcome, and the integral operation energy efficiency of the system is high.

The gradient utilization of geothermal energy: the traditional middle-deep geothermal heating is a hydrothermal type, but is not a closed heat exchange, and faces a recharging problem, the middle-deep geothermal heating in the invention adopts a middle-deep closed circulating heat pump system, hot water heated and circulated by a heat exchanger in a middle-deep geothermal well is used as a heat source, the recharging problem is avoided, but the heat exchange capacity is limited, at the moment, cascade utilization can be carried out, according to the depth of 200-2000 meters, the circulating water temperature is between 5 and 15 ℃, if the heat pump system is used for tail end heating, at least 45 ℃ water is required to enter a floor heating system, part of 5-15 ℃ water enters a heat pump unit evaporator, the requirement of 45 ℃ water heating of the floor heating system of a building is met through the improvement of the heat pump unit, meanwhile, part of 5-15 ℃ water is directly supplied into a capillary radiation system of a wall body, as shown in figures 3-4, so that the heat preservation performance of a building maintenance structure is improved by using lower temperature water, and bears part of outdoor cold load.

The specific embodiments described herein are merely illustrative of the spirit of the invention. Various modifications or additions may be made to the described embodiments or alternatives may be employed by those skilled in the art without departing from the spirit or ambit of the invention as defined in the appended claims.

Although the energy generating unit 1, the middle-deep buried pipe heat exchanging device 11, the middle-deep closed circulation well 111, the outer pipe 111a, the inner pipe 111b, the middle-deep well circulating water pump 112, the bypass pipeline 113, the first valve 114, the second valve 115, the third valve 116, the fourth valve 117, the solar photo-thermal heat collecting device 12, the solar photo-thermal heat collector 121, the heat collecting circulating water pump 122, the heat storage water tank 123, the photovoltaic power generation system 13, the energy storage unit 2, the electric heat storage boiler 21, the middle-deep geothermal heat pump 22, the electricity storage device 23, the heat supply load side pipeline 24, the water supply pipe 241, the water return pipe 242, the load side primary water pump 25, the load side secondary water pump 26, the energy using unit 3, the building terminal heating radiation floor 31, the building wall capillary radiation system 32, the electric device 33, the inner wall plastering 321, the outer wall 322, the wall 323, the floor heating system plastering plate 324, the floor heating system plastering plate 323, the floor heating system plastering plate 324, the floor heating system, Fixed grid 325, capillary network 326, etc., but does not exclude the possibility of using other terms. These terms are used merely to more conveniently describe and explain the nature of the present invention; they are to be construed as being without limitation to any additional limitations that may be imposed by the spirit of the present invention.