Passive energy-saving carbon emission reduction quantification method and system for building envelope structure

Abstract

The invention belongs to the field of thermal performance comprehensive testing of building envelope structures, and particularly relates to a passive energy-saving carbon emission reduction quantification method and system for a building envelope structure. The method comprises the following steps: deploying a sensing system on a to-be-measured enclosure structure, and synchronously acquiring heat flux density, indoor and outdoor temperature difference, solar radiation intensity and wind speed data; calculating a dynamic heat transfer coefficient based on the heat flow density and the temperature difference, comparing the dynamic heat transfer coefficient with a preset reference heat transfer coefficient, and quantifying the passive energy saving amount caused by the improvement of the thermal performance of the building envelope by combining the area of the building envelope and the calculation time; and further converting the energy saving amount into carbon emission reduction amount according to the carbon emission factor. Through direct monitoring and dynamic environmental parameter correction, accurate evaluation of the actual thermal performance of the enclosure structure is realized, passive and active energy-saving contributions are effectively distinguished, the authenticity and credibility of carbon emission reduction accounting are improved, and the method is suitable for building energy efficiency evaluation and carbon emission reduction verification.

Description

Technical Field

[0001] This invention belongs to the field of comprehensive testing of the thermal performance of building envelopes, and specifically relates to a method and system for quantifying passive energy saving and carbon emission reduction of building envelopes. Background Technology

[0002] Currently, building carbon emission reduction monitoring largely relies on the statistics and inference of total building energy consumption, indirectly estimating carbon reduction effects through energy consumption reductions. However, this method cannot accurately distinguish the source of energy-saving contributions: whether it stems from passive energy savings due to improved thermal performance of the building envelope, or from improved energy efficiency of active systems such as HVAC. Therefore, existing methods struggle to independently and accurately quantify the energy-saving contribution of the building envelope itself, exhibiting a significant "attribution ambiguity" problem.

[0003] Furthermore, traditional methods typically rely on static theoretical values ​​or design conditions for calculations, failing to adequately consider the impact of dynamic environmental parameters such as solar radiation, wind speed, and temperature differences on the thermal performance of the building envelope during actual operation. This leads to discrepancies between the assessment results and actual energy-saving effects. Simultaneously, there is a lack of effective monitoring methods for performance degradation of the building envelope due to material aging, moisture absorption, and deformation during long-term use. This hinders the assurance of the long-term accuracy of carbon emission reductions, limiting its credibility in carbon accounting and trading. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a method for quantifying passive energy-saving and carbon emission reduction in building envelopes. By directly monitoring the heat flux density and temperature difference of the building envelope, and combining dynamic corrections with environmental parameters such as solar radiation and wind speed, the method achieves accurate and dynamic calculation of the actual heat transfer coefficient of the building envelope. This effectively overcomes the evaluation bias caused by traditional methods relying on design values ​​or static models, and significantly improves the accuracy and authenticity of energy saving and carbon emission reduction calculations.

[0005] The technical solution adopted by this invention to solve its technical problem is: to provide a method for quantifying passive energy-saving carbon emission reduction in building envelopes, comprising the following steps:

[0006] S1: Deploy a sensing system on the building envelope of the building to be tested;

[0007] S2: The following data are synchronously collected at a preset frequency through the sensing system: heat flux density q, indoor and outdoor temperature difference ΔT, solar radiation intensity I, and wind speed v;

[0008] S3: Calculate the dynamic heat transfer coefficient K of the building envelope based on the heat flux density q and indoor-outdoor temperature difference ΔT collected in S2. current K current The average value over a preset time period;

[0009] S4: Establish the baseline heat transfer coefficient K for the building envelope. baseline K baseline The heat transfer coefficient when the performance of the building envelope has not degraded;

[0010] S5: Based on K baseline With K current The difference, combined with the area A of the enclosure structure and the calculation time t, is calculated using the formula ΔQ=(K baseline -K current )×ΔT×A×t to calculate the passive energy saving ΔQ of the enclosure structure;

[0011] S6: Obtain the carbon emission factor EF corresponding to the passive energy saving ΔQ, using the formula...

[0012] CarbonReduction = ΔQ × EF is used to calculate the passive energy-saving carbon emission reduction of the building envelope.

[0013] Furthermore, the sensing system includes:

[0014] A heat flux density sensor installed on the inner surface of the building envelope; a high-precision temperature sensor group that collects the indoor and outdoor temperatures of the building envelope; a solar radiation sensor that collects the outdoor solar radiation intensity; and a wind speed sensor that collects the outdoor wind speed.

[0015] Furthermore, in step S1, the heat flux density sensor is installed in a non-heat flux abnormal area of ​​the building envelope. The non-heat flux abnormal area is the middle part of the building envelope that avoids doors and windows, air conditioner outdoor units, and building corners, and the heat flux density sensor is completely attached to the inner surface of the building envelope.

[0016] Furthermore, in step S2, the preset frequency is every 5 minutes, and the data acquisition timestamp deviation of all sensors is ≤10s, and data synchronization is achieved through GPS time calibration.

[0017] Furthermore, in step S3, the preset time period is hourly or daily; if the calculation period is the winter heating season or the summer cooling season, K current It is also necessary to make corrections based on solar radiation intensity I and wind speed v. The correction formula is as follows:

[0018] K current '=K current ×(1-k1×I+k2×v),

[0019] Where k1 is the solar radiation correction factor; k2 is the wind speed correction factor; I is the solar radiation intensity; and v is the wind speed.

[0020] Furthermore, in step S4, K baseline Obtained through direct measurement, including the following steps:

[0021] The renovation project must be completed within 7 days of completion, and the new project must be completed within 15 days of passing the final acceptance inspection, and both must be completed before the building is put into normal use.

[0022] Deploy the same sensing system as in step S1, and shut down all active temperature control devices in the building;

[0023] Data is collected synchronously at the preset frequency in step S2, and continuous monitoring is conducted for no less than 7 days.

[0024] After removing days with abnormal weather and days with sensor malfunctions within the monitoring period, the average daily K value of the remaining valid days is taken as K. baseline The characteristics of an abnormal weather day are wind speed > 8 m / s or solar radiation > 1200 W / m. 2 .

[0025] Furthermore, in step S6, the carbon emission factor EF is matched with the energy type corresponding to the passive energy saving ΔQ.

[0026] Furthermore, it also includes step S7: tracking K calculated in step S3. current The trend of change, when K changes over N consecutive calculation periods current When the increase is greater than or equal to a preset threshold, an early warning of performance degradation of the building envelope is issued, where N is an integer greater than or equal to 3.

[0027] This invention also provides a passive energy-saving and carbon emission reduction quantification system for building envelopes, characterized in that it comprises:

[0028] The data acquisition module is used to collect the heat flux density q of the building envelope, the temperature difference ΔT between the inside and outside of the building envelope, and the external environmental parameters I and v in real time.

[0029] The data transmission module is used to transmit the data collected by the data acquisition module to the remote data processing and computing module;

[0030] The data processing and calculation module is used to receive data and perform the following functions:

[0031] K-value correction calculation function: Based on heat flux density q and temperature difference ΔT, and combined with the disturbance effect of external environmental parameters on the heat transfer of the building envelope surface, the dynamic heat transfer coefficient K of the building envelope is calculated. current ;

[0032] Passive energy-saving calculation function: based on K current With reference heat transfer coefficient K baseline The difference is used to calculate the instantaneous passive energy ΔQ;

[0033] Passive carbon reduction calculation function: Converts ΔQ into passive carbon reduction (CarbonReduction);

[0034] Performance degradation warning function: used for continuous monitoring of K current It tracks the changing trends over time and issues an early warning before the performance of the building envelope degrades to the preset energy-saving target value.

[0035] Furthermore, the data acquisition module includes: a heat flux density sensor, a high-precision temperature sensor group, a solar radiation sensor, and a wind speed sensor.

[0036] The present invention has the following beneficial effects:

[0037] (1) By directly monitoring the heat flux density and temperature difference of the building envelope and combining dynamic correction of environmental parameters such as solar radiation and wind speed, this invention achieves accurate and dynamic calculation of the actual heat transfer coefficient of the building envelope, effectively overcoming the evaluation bias caused by the reliance on design values ​​or static models in traditional methods, and significantly improving the accuracy and authenticity of energy saving and carbon emission reduction calculation.

[0038] (2) By establishing a benchmark heat transfer coefficient for the building envelope and comparing it with the current heat transfer coefficient monitored in real time, this invention can directly and independently quantify the passive energy saving brought about by the improvement of the building envelope's own performance, completely separating the contribution of "passive energy saving" from "active energy saving" such as HVAC, and solving the core problem of unclear attribution of building energy saving for a long time.

[0039] (3) The system of this application has long-term tracking and intelligent analysis capabilities, which can monitor the decay trend of thermal performance of the building envelope in real time and issue an early warning before the performance drops to a preset threshold, thereby providing a basis for building operation and maintenance, ensuring the continuity and reliability of energy saving and carbon emission reduction effects, and extending the effective service life of the building envelope. Attached Figure Description

[0040] To more clearly illustrate the technical solutions in the embodiments of this specification, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this specification. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0041] Figure 1 A flowchart illustrating a method and system for dynamic evaluation and optimization of building thermal performance based on digital twins, provided as an embodiment of this specification;

[0042] Figure 2 This is a schematic diagram illustrating the process of constructing an initial digital twin of a building based on a building information model, as provided in the embodiments of this specification. Detailed Implementation

[0043] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0044] The terms "first," "second," "third," etc., in the description, claims, and accompanying drawings are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to such processes, methods, products, or apparatus.

[0045] In the following description, terms such as “inner,” “outer,” “upper,” “lower,” “left,” and “right” are used only to facilitate the description of the embodiments and to simplify the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this specification.

[0046] All data involved in this application is information and data authorized by the user or fully authorized by all parties, and the collection of relevant data complies with the relevant laws, regulations and standards of the relevant countries and regions.

[0047] Example 1: This example uses the exterior wall envelope of an office building as an example to illustrate a method for quantifying passive energy conservation and carbon emission reduction in building envelopes, such as... Figure 1 As shown, it includes the following steps:

[0048] S1: Sensor System Deployment; Install a heat flux density sensor in the central area of ​​the inner surface of the building's exterior wall envelope (avoiding areas with abnormal heat flow such as windows and air conditioning units), ensuring complete contact with the wall surface without gaps. Arrange high-precision temperature sensor arrays on both the inner and outer sides of the envelope to simultaneously measure indoor and outdoor air temperatures. Install solar radiation and wind speed sensors on the building roof or in an open area facing south to collect outdoor environmental parameters.

[0049] S2: Data Synchronization Acquisition; All sensors synchronously acquire data such as heat flux density q, indoor and outdoor temperature difference ΔT, solar radiation intensity I, and wind speed v every 5 minutes via the built-in GPS time synchronization module, with timestamp deviation controlled within 10 seconds.

[0050] S3: Dynamic heat transfer coefficient Kcurrent calculate

[0051] Using an hourly calculation period, calculate the average K within that period based on the collected q and ΔT data. current Value. If it is the winter heating season or the summer cooling season, K needs to be adjusted. current Environmental modifications are performed using the following formula:

[0052] K current '=K current ×(1-k1×I+k2×v)

[0053] Where k1 is 0.0002 (W / m 2 ) -1 k2 is taken as 0.05s / m, I is the solar radiation intensity, and v is the wind speed.

[0054] S4: Baseline heat transfer coefficient K baseline Establishment: This building is a renovation project. Starting three days after the renovation is completed, all active temperature control devices will be turned off, and the same sensor system will be used for continuous monitoring for seven days. Data from one day with abnormal weather conditions (wind speed exceeding 8 m / s) will be excluded, and the average of the remaining six days' daily K values ​​will be taken as K. baseline The result was 0.45 W / (m²·K).

[0055] S5: Passive energy saving ΔQ calculation; the calculation time t is set to 1 month (720 hours), and the area A of the building envelope is 200m². 2 The average monthly ΔT is 15°C, and the current K current It is 0.48W / (m 2 ·K). Then:

[0056] ΔQ=(0.45-0.48)×15×200×720=-129,600kJ

[0057] Negative values ​​indicate a slight decrease in performance and should be addressed in conjunction with an early warning mechanism.

[0058] S6: Passive carbon emission reduction calculation; Assuming the building uses natural gas for heating, the corresponding carbon emission factor EF is 0.22 kgCO2 / kWh. After converting ΔQ to kWh, calculate the carbon emission reduction:

[0059] CarbonReduction = ΔQ × EF. In practical applications, EF needs to be matched according to the energy type.

[0060] S7: Performance degradation warning; continuous system monitoring K current The threshold is set to K for three consecutive months. current An increase exceeding 5% triggers an alert. In this embodiment, K currentThe value increased from 0.45 to 0.48, an increase of 6.7%, and the system automatically issued a maintenance prompt.

[0061] Example 2: As Figure 2 As shown, a passive energy-saving carbon emission reduction quantification system for building envelope includes:

[0062] The data acquisition module is used to collect the heat flux density q of the building envelope, the temperature difference ΔT between the inside and outside of the building envelope, and the external environmental parameters I and v in real time.

[0063] The data transmission module is used to transmit the data collected by the data acquisition module to the remote data processing and computing module;

[0064] The data processing and calculation module is used to receive data and perform the following functions:

[0065] K-value correction calculation function: Based on heat flux density q and temperature difference ΔT, and combined with the disturbance effect of external environmental parameters on the heat transfer of the building envelope surface, the dynamic heat transfer coefficient K of the building envelope is calculated. current ;

[0066] Passive energy-saving calculation function: based on K current With reference heat transfer coefficient K baseline The difference is used to calculate the instantaneous passive energy ΔQ;

[0067] Passive carbon reduction calculation function: Converts ΔQ into passive carbon reduction (CarbonReduction);

[0068] Performance degradation warning function: used for continuous monitoring of K current It tracks the changing trends over time and issues an early warning before the performance of the building envelope degrades to the preset energy-saving target value.

[0069] Furthermore, the data acquisition module includes a heat flux density sensor, a high-precision temperature sensor group, a solar radiation sensor, and a wind speed sensor, which are responsible for collecting the thermal and environmental parameters of the building envelope in real time.

[0070] This invention achieves accurate, dynamic, and traceable quantitative assessment of passive energy-saving carbon emission reductions in buildings by directly monitoring the thermal performance of the building envelope, combined with environmental parameter correction and benchmark model comparison. The system possesses good engineering applicability and data reliability, making it suitable for verifying energy-saving effects and calculating carbon emission reductions in both new and renovated buildings.

[0071] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for quantifying passive energy-saving carbon emission reduction in building envelopes, characterized in that, Includes the following steps: S1: Deploy a sensing system on the building envelope of the building to be tested; S2: The following data are synchronously collected at a preset frequency through the sensing system: heat flux density q, indoor and outdoor temperature difference ΔT, solar radiation intensity I, and wind speed v; S3: Calculate the dynamic heat transfer coefficient K of the building envelope based on the heat flux density q and indoor-outdoor temperature difference ΔT collected in S2. current K current The average value over a preset time period; S4: Establish the baseline heat transfer coefficient K for the building envelope. baseline K baseline The heat transfer coefficient when the performance of the building envelope has not degraded; S5: Based on K baseline With K current The difference, combined with the area A of the enclosure structure and the calculation time t, is calculated using the formula ΔQ=(K baseline -K current )×ΔT×A×t to calculate the passive energy saving ΔQ of the enclosure structure; S6: Obtain the carbon emission factor EF corresponding to the passive energy saving ΔQ, using the formula... CarbonReduction = ΔQ × EF is used to calculate the passive energy-saving carbon emission reduction of the building envelope.

2. The method for quantifying passive energy-saving carbon emission reduction in building envelopes according to claim 1, characterized in that, The sensing system includes: A heat flux density sensor installed on the inner surface of the building envelope, a high-precision temperature sensor group that collects the indoor and outdoor temperatures of the building envelope, a solar radiation sensor that collects the outdoor solar radiation intensity, and a wind speed sensor that collects the outdoor wind speed.

3. The method for quantifying passive energy-saving carbon emission reduction in building envelopes according to claim 1, characterized in that, In step S1, the heat flux density sensor is installed in the non-heat flux abnormal area of ​​the building envelope. The non-heat flux abnormal area is the middle part of the building envelope that avoids doors, windows, air conditioner outdoor units, and building corners, and the heat flux density sensor is completely attached to the inner surface of the building envelope.

4. The method for quantifying passive energy-saving carbon emission reduction in building envelopes according to claim 1, characterized in that, In step S2, the preset frequency is every 5 minutes, and the data acquisition timestamp deviation of all sensors is ≤10s. Data synchronization is achieved through GPS time calibration.

5. The method for quantifying passive energy-saving carbon emission reduction in building envelopes according to claim 1, characterized in that, In step S3, the preset time period is hourly or daily; if the calculation period is the winter heating season or the summer cooling season, K current It is also necessary to make corrections based on solar radiation intensity I and wind speed v. The correction formula is as follows: K current '=K current ×(1-k1×I+k2×v); Where k1 is the solar radiation correction factor; k2 is the wind speed correction factor; I is the solar radiation intensity; and v is the wind speed.

6. The method for quantifying passive energy-saving carbon emission reduction in building envelopes according to claim 1, characterized in that, In step S4, K baseline Obtained through direct measurement, including the following steps: The renovation project must be completed within 7 days of completion, and the new project must be completed within 15 days of passing the final acceptance inspection, and both must be completed before the building is put into normal use. Deploy the same sensing system as in step S1, and shut down all active temperature control devices in the building; Data is collected synchronously at the preset frequency in step S2, and continuous monitoring is conducted for no less than 7 days. After removing days with abnormal weather and days with sensor malfunctions within the monitoring period, the average daily K value of the remaining valid days is taken as K. baseline The characteristics of an abnormal weather day are wind speed > 8 m / s or solar radiation > 1200 W / m. 2 .

7. The method for quantifying passive energy-saving carbon emission reduction in building envelopes according to claim 1, characterized in that, In step S6, the carbon emission factor EF is matched with the energy type corresponding to the passive energy saving ΔQ.

8. The method for quantifying passive energy-saving carbon emission reduction in building envelopes according to claim 1, characterized in that, It also includes step S7: tracking the K calculated in step S3 current The trend of change, when K changes over N consecutive calculation periods current When the increase is greater than or equal to a preset threshold, an early warning of performance degradation of the building envelope is issued, where N is an integer greater than or equal to 3.

9. A system for implementing the passive energy-saving carbon emission reduction quantification method for building envelopes according to any one of claims 1-8, characterized in that, include: The data acquisition module is used to collect the heat flux density q of the building envelope, the temperature difference ΔT between the inside and outside of the building envelope, and the external environmental parameters I and v in real time. The data transmission module is used to transmit the data collected by the data acquisition module to the remote data processing and computing module; The data processing and calculation module is used to receive data and perform the following functions: K-value correction calculation function: Based on heat flux density q and temperature difference ΔT, and combined with the disturbance effect of external environmental parameters on the heat transfer of the building envelope surface, the dynamic heat transfer coefficient K of the building envelope is calculated. current ; Passive energy-saving calculation function: based on K current With reference heat transfer coefficient K baseline The difference is used to calculate the instantaneous passive energy ΔQ; Passive carbon reduction calculation function: Converts ΔQ into passive carbon reduction (CarbonReduction); Performance degradation warning function: used for continuous monitoring of K current It tracks the changing trends over time and issues an early warning before the performance of the building envelope degrades to the preset energy-saving target value.

10. A passive energy-saving carbon emission reduction quantification system for building envelope according to claim 9, characterized in that, The data acquisition module includes: a heat flux density sensor, a high-precision temperature sensor group, a solar radiation sensor, and a wind speed sensor.

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