Energy system sustainability quantitative evaluation method

Abstract

The invention discloses an energy system sustainability quantitative evaluation method, which comprises the four steps of system identification and feature extraction, system full life cycle process list extraction, system sustainability footprint quantification and system sustainability index calculation, and is characterized in that firstly, the architecture, mechanism and the like of a target energy system are identified, and feature data are extracted; then extracting full life cycle process list data, including system operation, equipment construction, raw material production and waste resource recovery; sustainability footprints of the system in the aspects of raw materials, energy, pollutants, economy and the like are quantified; according to the method, the limitation of qualitative expression is broken through, energy, environment and economy multi-dimensional quantitative evaluation of the whole life cycle is realized, a clear basis is provided for energy system optimization decision making, and the method has the advantages of systematicness, comprehensiveness, practicability and the like.

Description

Technical Field

[0001] This invention belongs to the field of energy and power system assessment technology, specifically a quantitative assessment method for the sustainability of energy systems, involving four parts: system identification and feature extraction, extraction of the system's full life cycle process inventory, quantification of the system's sustainability footprint, and calculation of system sustainability indicators. Background Technology

[0002] Sustainability is often used as a development model to guide sustainable development across various industries, such as construction, transportation, energy and power, marine fisheries, the digital economy, and education. Sustainable development in the energy and power industry includes the utilization of renewable energy resources, the promotion of new energy electric vehicles, new energy storage technologies, new power systems, and zero-carbon industrial park energy systems. However, in energy and power systems, sustainability is often described qualitatively, reflected in the proportion of renewable energy in the system, advanced energy utilization technologies such as cascade utilization, and clean and low-carbon behaviors such as green certificate carbon trading. There is a lack of systematic quantitative methods for assessing system sustainability.

[0003] Currently, common energy system assessment methods mainly include techno-economic assessment and life cycle assessment. Techno-economic assessment is the most widely used method, analyzing two main aspects: first, technical performance, including energy conversion efficiency, operational efficiency, and system reliability; and second, economic benefits, such as return on investment, net present value, and internal rate of return. However, this method is highly dependent on system structure, operational assumptions, and external environmental factors, and is significantly affected by uncertainty. Furthermore, it lacks a systematic and comprehensive approach covering the entire life cycle. Life cycle assessment, on the other hand, is a quantitative assessment method based on empirical data, capable of systematically assessing the environmental impact of an energy system throughout its entire life cycle. However, this method primarily focuses on environmental factors and fails to fully consider the system's technical and economic performance, thus having certain limitations in comprehensive assessment.

[0004] Therefore, research that breaks through the inertia of qualitative descriptions of sustainability and overcomes the limitations of traditional methods to develop a comprehensive and systematic assessment method for energy systems is an inevitable trend. Summary of the Invention

[0005] The purpose of this invention is to overcome the limitations of qualitative descriptions of energy system sustainability and provide a quantitative assessment method for sustainability that covers the entire life cycle and multiple dimensions of "energy, environment, and economy," as well as comprehensive temporal and spatial dimensions. This method aims to systematically, comprehensively, and quantitatively assess the sustainability of energy systems and provide a clear basis for energy system optimization and decision-making.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solution: This invention discloses a method for quantitatively assessing the sustainability of energy systems, comprising the following steps: Step 1: Conduct system identification and feature extraction for the target energy system. System identification identifies the system's architecture, operating mechanism, equipment composition, operating conditions, and operating constraints. Feature extraction, based on system identification, extracts specific data parameters of environmental features, equipment features, and operating features. Step 2: Extract the system's full lifecycle process inventory to determine the direct process inventory data involved in the entire lifecycle from construction and operation to recycling; Step 3: Conduct a quantitative analysis of the system's sustainability footprint. Based on the system's full lifecycle process inventory data, and using years as the time unit, quantitatively demonstrate the system's sustainability performance footprint. Step 4: Based on steps 1 to 3, calculate the system sustainability index values.

[0007] Preferably, step 2 specifically includes the following sub-steps: Step 2.1: Based on the operation process of the energy system, determine the system input and output parameters, operating parameters, and energy conversion; Step 2.2: Based on the installation capacity of each device obtained in Step 2.1, determine the raw materials, power consumption, investment cost, maintenance cost, and service life of the device. Step 2.3: Based on the amount of raw materials obtained in Step 2.2, calculate the electrical energy consumed and the air pollutants emitted in producing the raw materials; Step 2.4: Based on the data from Steps 2.1 to 2.3, calculate the amount of waste heat and solid waste recovered during system operation, as well as the amount of raw materials recovered after the service ends.

[0008] Preferably, step 3 specifically includes the following sub-steps: Step 3.1: Raw material consumption and recycling. Determine the initial consumption, recycling amount, and final consumption of each raw material. The calculation formula is as follows: ; in, and Vectors representing the initial consumption, recovery, and final consumption of the five raw materials, respectively; A vector representing the installed capacity of 8 devices; A matrix representing the consumption coefficients of raw materials by the installed equipment; Step 3.2: Energy Flow. Considering the electricity consumption and recovery from raw material production, the electricity consumption during equipment production, and the energy conversion and losses during system operation, the formula for calculating the electricity consumption for raw material production is: ; in, This represents the total electricity consumption for raw material production. Let be the final consumption of the i-th raw material; The energy consumption coefficient for raw materials; i represents the i-th type of raw material; N is the service life of the equipment; The formula for calculating the power consumption of equipment in production is: ; in, N represents the total power consumption of the equipment during production; N represents the service life of the equipment. Let j be the installation capacity of the j-th type of equipment; Let be the power consumption coefficient for the j-th type of equipment; The formulas for calculating energy conversion and loss during system operation are as follows: ; in, It is the total demand for the k-th type of energy at time t. It is the total production of energy type k at time t; k represents the energy type of cold, heat, electricity, gas, and biomass; G represents the output of the equipment; and the superscripts gen, dem, pc, and sell represent production, demand, purchase, and sale, respectively. Step 3.3: Emissions of six air pollutants, including those from raw material production, equipment manufacturing processes, and energy trading during system operation. The formula for calculating raw material pollutant emissions is: ; The formula for calculating pollutant emissions during equipment production is as follows: ; The formula for calculating pollutant emissions caused by the k-th type of energy trading during system operation is as follows: ; The formula for calculating the total annual emissions of pollutant type n is: ; in, Let n be the total annual emissions of the nth pollutant; The emission of the nth type of pollutant produced from raw materials; The nth type of pollutant emitted during the equipment's production process; Let n be the amount of pollutant emitted at time t resulting from the k-th type of energy trading during system operation. Step 3.4: Emissions of three equivalent pollutants. The six air pollutants are converted into three main equivalent pollutants. The calculation formula is as follows: ; in, Let m be the emission amount of the equivalent pollutant. It is the equivalent conversion factor of the m-th equivalent pollutant for the n-th pollutant; Let n be the emission amount of the nth pollutant; Step 3.5: Process the data from Steps 3.1 to 3.4 through market mechanisms to obtain economic footprint data, including equipment investment and maintenance costs, pollutant tax costs, system operating costs and profits, carbon trading costs and profits, and green certificate trading and profits; The formula for calculating annual investment and maintenance costs is: ; in, Annual investment cost; Annual maintenance costs; This is the operation and maintenance coefficient; This is the return on investment coefficient; Profit margin; Let j be the installation capacity of the j-th type of equipment; The investment and maintenance cost coefficient for equipment type j is given; N is the service life of the equipment; the formula for calculating pollutant tax costs is: ; This is the emission penalty factor for the m-th equivalent pollutant. The formula for calculating energy trading costs or profits during system operation is as follows: ; In the formula, This represents the cost and profit of trading the k-th type of energy; Represents the cost coefficient and profit coefficient of the k-th energy type; Let be the amount of the k-th type of energy purchased at time t; Let be the amount of the k-th type of energy sold at time t; The formulas for calculating carbon trading costs and profits are as follows: ; and These are the costs and profits of the carbon trading market, respectively. This refers to the carbon trading price coefficient. and For CO2 emissions and emission quotas; The formula for calculating the transaction costs and profits of green certificates is as follows: ; and These are the costs and profits associated with green certificate transactions; The price coefficient for green certificates; The green certificate quota that the community needs to meet; For the number of community green certificates; The renewable energy generation quota ratio coefficient in the community energy system; This represents the total electricity demand of the community during the operating cycle. This refers to the total amount of renewable energy generated by the community during the operating cycle.

[0009] Preferably, step 4 specifically includes the following sub-steps: Step 4.1: System performance indicators, including equipment operating efficiency and system operating efficiency; The formula for calculating equipment operating efficiency is: ; in, To improve equipment operating efficiency; To output energy to the equipment; Input energy into the equipment; The formula for calculating system operating efficiency is: ; Step 4.2: Energy performance indicators, including energy conversion efficiency, renewable energy share, and primary energy saving rate. The formula for calculating energy conversion efficiency is: ; For system operating efficiency; For energy conversion efficiency; These are the electrical load and heat load requirements, respectively. The sales volumes are for biomass energy, electricity, heat energy, and gas energy, respectively. These are the purchase volumes of solar energy, geothermal energy, biomass energy, electricity, heat energy, and gas energy, respectively; the formula for calculating the proportion of renewable energy is: ; in, The proportion of renewable energy; These represent the production volumes of solar energy, geothermal energy, and biomass energy, respectively; the primary energy saving rate satisfies the formula: ; in, Represents primary energy consumption. To compare the primary energy consumption of the system; This represents the primary energy consumption of the target system, with the subscripts sys and ref representing the target system and the comparison system, respectively. Step 4.3: Environmental performance indicators, including the annual air pollutant emission reduction rate, calculated using the following formula: ; In the formula, Let m be the annual emission reduction rate of the equivalent pollutant. To compare the annual emissions of the m-th equivalent pollutant in the system; Let m be the annual emission of the m-th equivalent pollutant in the target system; when m = CO2 - eq., This represents the equivalent annual reduction in carbon dioxide emissions, which is equivalent to the reduction in global warming potential; when m = SO2 - eq., This represents the equivalent annual reduction in sulfur dioxide emissions, which is equivalent to the reduction in acidification potential; when m = PM2.5 - eq., This represents the equivalent annual reduction in inhalable particulate matter emissions, which is equivalent to the reduction in the potential impact on human respiratory health. Step 4.4: Economic performance indicators, including the annual total cost savings rate, calculated using the following formula: ATCSR is the annual total cost savings rate. To compare the system's total annual cost; The total annual cost of the target system.

[0010] Preferably, the system inputs in step 1 include biomass energy, solar energy, geothermal energy, purchased biomass energy, electrical energy, gas energy, thermal energy, and cold energy; the system outputs include sold biomass energy, gas energy, electrical energy, thermal energy, and cold energy; the system equipment in step 1 includes a gasifier, photovoltaic system, ground source heat pump, improved internal combustion engine, organic Rankine cycle module, heat exchanger, battery, and thermal storage tank.

[0011] Preferably, the input and output parameters in step 2.1 include light intensity, temperature, wind speed, electrical load, heat load, and energy trade volume; the operating parameters include the installed capacity of each device; energy conversion includes energy flow direction and balance, and energy loss; and the air pollutants in step 2.3 include CO, CO2, CH4, SO2, and NO. x PM 2.5 .

[0012] Preferably, the three equivalent pollutants in step 3.4 are CO2-eq, SO2-eq, and PM2.5. 2.5 -eq.

[0013] Preferably, the equipment in the equipment operating efficiency of step 4.1 includes photovoltaics, gasifiers, internal combustion engines, organic Rankine cycles, ground source heat pumps, thermal storage tanks, electric refrigeration equipment, and gas boilers; the renewable energy in step 4.2 includes solar energy, biomass energy, and geothermal energy.

[0014] Preferably, the annual air pollutant emission reduction rate in step 4.3 targets pollutants including CO2-eq, SO2-eq, and PM2.5. 2.5 -eq.

[0015] This invention discloses an energy system comprising an energy input unit, an energy conversion unit, an energy storage unit, an energy output unit, and a control unit, wherein each unit is sequentially connected and operates collaboratively via an energy transmission path. The energy input unit includes a renewable energy acquisition module and a purchased energy access module. The renewable energy acquisition module includes photovoltaic modules, a biomass raw material supply device, and a geothermal energy acquisition device. The purchased energy access module is used to access purchased electricity and natural gas. The energy conversion unit includes a biomass gasifier, an internal combustion engine, an organic Rankine cycle module, a ground source heat pump, an electric refrigeration device, and a heat exchanger. The biomass gasifier is connected to the internal combustion engine to convert biomass energy into mechanical energy and then into electrical energy. The high-temperature exhaust gas and cylinder liner water of the internal combustion engine are connected to the organic Rankine cycle module to recover energy. The ground source heat pump and the heat exchanger work together to achieve cold / heat energy conversion. The energy storage unit includes a battery, a thermal / cold storage tank, and a gas tank, which are used to store electrical energy, cold / heat energy, and biomass gas produced by biomass gasification, respectively. The energy output unit is used to supply electricity, heat, cold energy and biomass gas to the outside to meet the end load demand; the control unit is used to regulate the operating parameters of each unit to ensure energy and power balance, equipment operation compliance and energy supply and demand timing matching.

[0016] Timing matching is required.

[0017] Beneficial effects: It provides a systematic process and steps for quantifying sustainability, establishes methods, assessment indicators, and evaluation systems for calculating sustainability footprints, and provides methodological guidance for subsequent sustainability research; it breaks through the limitations of traditional techno-economic assessments that lack a systematic approach across the entire life cycle and time, and expands the boundaries of traditional life cycle assessments which are limited to the environmental field and spatial scale, enabling a more comprehensive and systematic assessment of the sustainability performance of energy and power systems; in the calculation of sustainability indicators, it introduces comparative analysis methods based on historical data, standard systems, or reference systems, and overcomes the dependence of traditional assessment methods on system structure, operational assumptions, and external environmental factors through the use of savings rates, highlighting the management optimization and improvement of the system, and providing clearer assessment objectives and decision-making basis. Attached Figure Description

[0018] Figure 1 This is a system flow diagram of the present invention.

[0019] Figure 2 This is an example energy system architecture diagram of the present invention.

[0020] Figure 3 This is a schematic diagram illustrating the relationship between the extraction of the full life cycle process inventory and the sustainability footprint of the system of this invention.

[0021] Figure 4This is an energy system architecture diagram used for comparison and reference in this invention.

[0022] Figure 5 This is a schematic diagram illustrating representative sustainability indicators of an energy system in a typical case of this invention. Detailed Implementation

[0023] The following will refer to the accompanying drawings in the embodiments of the present invention. Figures 1 to 5 The technical solutions in the embodiments of the present invention are clearly and completely described herein. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0024] Figure 1 The process of quantitative assessment of energy system sustainability is presented in four steps: Step 1: System identification and feature extraction; Step 2: Extraction of the system's full life cycle process list; Step 3: Quantification of the system's sustainability footprint; and Step 4: Calculation of system sustainability indicators. This clearly presents the complete assessment logic from system cognition to indicator quantification. Figure 2 The multi-energy coupling system flowchart integrates biomass, solar energy, and geothermal energy. Through equipment such as gasifiers, photovoltaics, improved internal combustion engines, organic Rankine cycles, and ground source heat pumps, it achieves power generation, heat generation, and cooling generation. At the same time, it is equipped with energy storage and heat / cooling storage devices, reflecting the system architecture of multi-energy synergy and energy storage. Figure 3 The diagram showing the relationship between the system's entire life cycle and its sustainable activity footprint is presented on the left, showing the resource & materials, equipment & system operation, and service termination stages of the system's entire life cycle. The right side corresponds to the sustainable footprint of energy activities, environmental activities, and economic activities, intuitively demonstrating the relationship between each stage of the entire life cycle and the sustainable dimension. Figure 4 Referring to the energy supply system flowchart, the main power grid supplies power to the electrical load and electric refrigeration equipment, while natural gas supplies heat to the heat load through gas furnaces and heat exchangers. This is the traditional energy supply model used for comparison. Figure 5 The bar chart illustrates the effectiveness indicators of the quantitative assessment of energy system sustainability, including primary energy savings of 67.21%, air pollutant emission reduction rates (CO2-eq 74.85%, SO2-eq 53.60%, PM2.5%), and PM2.5 emission reduction rates. 2.5 -eq51.69%) and annual total cost savings rate of 54.21%, intuitively showcasing the system's improvement in energy, environment, and economy.

[0025] Invention Content / Principle: The purpose of this invention is to propose a quantitative assessment method for the sustainability of energy systems (the energy system in this invention can be selected according to actual needs, without specific restrictions). The specific method includes the following steps: System identification and feature extraction: For the target energy system, identify its composition architecture, operating mechanism, equipment composition, operating conditions, and operating constraints; and extract specific data parameters of environmental characteristics, equipment characteristics, and operating characteristics to provide data support for subsequent steps. System life cycle process inventory extraction: Determine the inventory data of direct processes involved in the entire life cycle from construction and operation to recycling, including system operation (input and output, operating parameters, energy conversion), equipment construction (raw material consumption, electricity consumption, service life, investment cost), raw material production (electricity consumption, air pollutant emissions), and waste resource recycling (raw materials, waste heat, solid waste), etc. System sustainability footprint quantification: Based on the system life cycle process inventory data, using years as the time unit, quantitatively display the system's sustainability performance footprint in terms of raw material consumption and recycling, energy flow, air pollutant emissions, equivalent air pollutant emissions, and economic activity costs. System sustainability index calculation: Calculate system performance indicators (equipment operating efficiency, system operating efficiency), energy performance indicators (energy conversion efficiency, renewable energy ratio, primary energy saving rate), environmental performance indicators (air pollutant emission reduction rate), economic performance indicators (annual total cost saving rate), etc., to quantitatively assess the sustainability of the energy system.

[0026] Example 1: As Figure 1 The present invention illustrates a method for quantitatively assessing the sustainability of an energy system, which specifically includes the following steps: Step 1: Conduct system identification and feature extraction for the target energy system. Specifically, this includes: Step 1.1: System identification, which involves identifying the system's architecture and operating mechanisms, including system equipment composition, operating conditions, operating mechanisms, and operating constraints; Step 1.2: Feature extraction, which, based on system identification, identifies and extracts specific data parameters such as environmental features, equipment features, and operational features to provide data support for subsequent steps. This step corresponds to the system identification and feature extraction stage, covering the identification of system architecture and operating mechanisms, as well as the extraction of environmental features, equipment features, and operational features. Step 2: Building upon Step 1, extract the system's entire lifecycle process inventory. This step aims to extract the direct process inventory data involved in the entire lifecycle from construction and operation to recycling. The key lies in moving from result to cause, from the whole to the part, from external manifestation to internal operation, and finally to the operational process of the specific carrier. Specifically, this includes: Step 2.1: First, based on the energy system's operation process, determine the system's input and output parameters (such as light intensity, temperature, wind speed, electrical load, heat load, energy trade volume, etc.), operating parameters (such as the installed capacity of each piece of equipment), and energy conversion (such as energy flow direction and balance, energy loss, etc.); Step 2.2: Based on the installed capacity of each piece of equipment obtained in Step 2.1, determine the raw materials consumed in producing that equipment, the electricity consumption, investment cost, maintenance cost, and service life; Step 2.3: Based on the amount of raw materials obtained in Step 2.2, calculate the electrical energy consumed in producing that raw material and the air pollutants emitted; Step 2.4: Combining the data from Steps 2.1 to 2.3, calculate the amount of waste heat and solid waste recovered during system operation, and the amount of raw materials recovered after the service ends. This step corresponds to the extraction of the system's full lifecycle process list, covering aspects such as system operation (input / output, operating parameters, energy conversion), equipment construction (raw material consumption, power consumption, service life, investment cost), raw material production (pollutant emissions, power consumption), and waste resource recycling (raw materials, waste heat, solid waste).

[0027] Step 3: Building upon Step 2, conduct quantification of the system's sustainability footprint. The key to this step is to quantify the system's sustainability footprint (data on raw materials, energy, pollutants, costs, etc.) based on the system's full lifecycle process inventory data, using a fixed time unit (e.g., year). Specifically, this includes: Step 3.1: Raw material consumption and recycling, clarifying the initial consumption, recycling, and final consumption of each raw material; involving raw materials such as steel, aluminum, copper, PVC, and glass; Step 3.2: Energy flow, considering electricity consumption and recycling in raw material production, electricity consumption in equipment production processes, and energy conversion and losses during system operation (cold, heat, electricity, gas, biomass, etc.); Step 3.3: Emissions of six air pollutants (including those caused by raw material production, equipment production processes, energy production during system operation, and energy purchased during energy trading), covering CO, CO2, CH4, SO2, and NO. x PM 2.5Step 3.4: Emissions of three equivalent pollutants (converting six air pollutants into three main equivalent pollutants to measure their potential impact on the greenhouse effect, rainwater acidification, and human respiration), namely CO2-eq, SO2-eq, and PM2.5-eq; Step 3.5: Processing the data from Steps 3.1 to 3.4 through market mechanisms to obtain economic footprint data, including equipment investment and maintenance costs, pollutant tax costs, system operating costs and profits, carbon trading costs and profits, green certificate trading and profits, etc. This step corresponds to the quantification of the system's sustainability footprint, involving raw material consumption and its recovery, energy flow (electricity, heat, cooling, gas, biomass, etc.), air pollutant production and equivalent emissions, and economic activity costs or profits.

[0028] Step 4: Based on Steps 1 to 3, calculate the system sustainability indicators to further quantify sustainability performance. Specifically, this includes: Step 4.1: System performance indicators, including equipment operating efficiency and system operating efficiency; Step 4.2: Energy performance indicators, including energy conversion efficiency, renewable energy share, renewable energy absorption rate, and primary energy saving rate; Step 4.3: Environmental performance indicators, including air pollutant emission reduction rate, global warming potential, acidification potential, and potential impact on human respiratory health; Step 4.4: Economic performance indicators, including return on investment, net present value, internal rate of return, green revenue share, and annual total cost saving rate. This step corresponds to the system sustainability indicator calculation stage, covering the calculation of four major categories of indicators: system performance, energy performance, environmental performance, and economic performance.

[0029] Example 2: The operation steps are as follows (using...) Figure 2 (The example system shown is an example.)

[0030] Step 1: Targeting Figure 2 The system shown in the example is used for system identification and feature extraction.

[0031] 1.1 System identification requires clarifying the system's constituent components, system architecture, operating mechanism, operating constraints, and other characteristics.

[0032] Energy inputs include three renewable energy sources: biomass energy, solar energy, and geothermal energy; energy outputs include electricity, heat, cooling, and gas (primarily methane). The system equipment comprises a gasifier, photovoltaic system, ground-source heat pump, improved internal combustion engine, organic Rankine cycle module, heat exchanger, battery, and thermal storage tank. This invention uses mature models for method description, and modifications can be made as needed.

[0033] The operating mechanism includes a coupling mechanism for the mutual conversion of five energy sources: cold, heat, electricity, gas, and biomass; and a trading mechanism for participating in external markets. For example, solar energy is converted into electricity through photovoltaic units; biomass energy is used to produce biomass gas, mainly composed of methane, through a gasifier. This product gas can participate in the gas trading market or be used for combustion in internal combustion engines to generate electricity; the waste heat from the high-temperature exhaust gas of the internal combustion engine is recovered by the organic Rankine cycle module to produce electricity and heat; the waste heat from the high-temperature cylinder liner water of the internal combustion engine is recovered and used for reheating the high-temperature heat source of the ground source heat pump in heating mode; geothermal energy is used to produce heat and cold energy through the ground source heat pump; and batteries and thermal storage tanks are used by users to temporarily store excess electrical, cold, and heat energy to improve flexibility (disabled by default). Operating constraints are presented in a power balance manner for the five energy sources: cold, heat, electricity, gas, and biomass.

[0034] 1.2. Feature Extraction: Based on the system's recognition process, data features are extracted. The specific data table is as follows:

[0035] Step 2: Based on Step 1, further extract the system's full lifecycle inventory data, including system operation, equipment construction, raw material production, and waste resource recycling; this invention provides a set of data parameters for reference.

[0036] 2.1. During the system operation phase, it is necessary to clearly define the system's inputs, outputs, equipment operating parameters, and energy conversion quantities, as detailed in the table below:

[0037] During the system operation phase, the purchased traditional energy resources will generate pollutant emissions, with specific emission coefficients as follows:

[0038] 2.2 During the equipment construction phase, it is necessary to determine the raw materials and electricity consumed in the construction process based on the equipment installation capacity, and to determine the service life, investment cost, and other data of the equipment.

[0039] 2.3 Raw Material Production Stage: Based on the raw material consumption determined in stage 2.2 of Example 2, the energy consumption and the consumption of six pollutants (CO, CO2, CH4, SO2, NO) in the raw material production process design are further determined. x PM 2.5 Emissions, with specific conversion indicators as follows:

[0040] For emissions of six pollutants, they can be converted into three equivalent pollutant emissions to correspond to their specific environmental impacts: greenhouse potential - equivalent carbon dioxide emissions (CO2). 2- eq.), acidification potential - equivalent sulfur dioxide emissions (SO2). 2- eq.), potential impact on human respiratory function - inhalable air pollutant particles (PM 100). 2.5- (eq.), the equivalent conversion factors are shown in the table below:

[0041] 2.4 The waste resource recycling stage mainly includes raw material recycling, waste heat recovery, and solid waste recycling. Among them, raw material recycling takes into account high-value raw materials such as steel, aluminum, and copper with a recycling coefficient of 0.9; waste heat recovery is reflected in the energy conversion process during system operation; and solid waste is reflected in the solid waste recycling in the park or community where the system is located.

[0042] Step 3: Building upon the first two steps in Implementation 2, organize the system's entire lifecycle data and complete the data quantification. The quantification of the system's entire lifecycle and sustainability footprint is as follows: Figure 3 As shown. Specific quantitative content includes raw materials, energy flow, air pollutant emissions, equivalent air pollutant emissions, and economic activity costs or profits.

[0043] 3.1 Raw material consumption and recycling: clearly define the initial consumption, recycling, and final consumption of each raw material.

[0044] ; in, and Vectors representing the initial consumption, recovery, and final consumption of the five raw materials, respectively; A vector representing the installed capacity of 8 devices; A matrix representing the consumption coefficients of raw materials by the installed equipment; 3.2 Energy flow, considering the power consumption of raw material production (including raw material recycling), the power consumption of equipment production process, and the energy conversion and loss (cold, heat, electricity, gas, biomass, etc.) during system operation.

[0045] The electricity consumption for raw material production is calculated as follows: ; Here, represents the energy consumption coefficient for raw materials; i represents the i-th type of raw material; N is the service life of the equipment. The power consumption of the equipment during production is calculated as follows: ; Let be the power consumption coefficient for the j-th type of equipment; j represents the j-th type of equipment. The energy conversion and losses involved in the system operation process include the production, demand, sales, and purchase of various types of energy in the system. ; In the formula, k Representing energy types such as cold, heat, electricity, gas, and biomass; G Represents the output of the equipment; superscript gen, dem, PC, Sell These represent production, demand, purchase, and sale, respectively.

[0046] 3.3 Emissions of six air pollutants (including those from raw material production, equipment manufacturing processes, and energy trading during system operation). Calculation of pollutant emissions from raw materials: ; In the formula, the subscript The types of pollutants; A matrix of pollutant emissions from raw materials; For traditional power production n Various pollutant emissions. Calculation of pollutant emissions during equipment production process: ; Calculation of pollutant emissions resulting from the k-th energy transaction during system operation: ; In summary, the first n The total annual emissions of pollutants are calculated as follows: .

[0047] 3.4 Emissions of three equivalent pollutants (the six air pollutants are equivalently converted into three main equivalent pollutants to measure the potential impact on the greenhouse effect, rainwater acidification, human respiration, etc.).

[0048] .

[0049] In the formula, For the first n The first pollutant m Equivalent conversion factor for equivalent pollutants.

[0050] 3.5 Obtain economic footprint data by processing the data in 3.1 to 3.4 of Example 2 through market mechanisms, including equipment investment and maintenance costs, pollutant tax costs, system operation costs and profits, carbon trading costs and profits, green certificate trading and profits, etc.

[0051] The annual investment and maintenance costs are calculated as follows: ; Annual investment cost; Annual maintenance costs; The maintenance coefficient is 0.02. This is the return on investment coefficient; The profit margin is 0.06. Let j be the installation capacity of the j-th type of equipment; The investment and maintenance cost coefficient for equipment type j; N is the service life of the equipment; pollutant tax cost: ; The equivalent emission penalty factor for the m-th pollutant is shown in the table below:

[0052] The energy trading costs or profits during system operation are calculated as follows: ; In the formula, This represents the cost and profit of trading the k-th type of energy; The cost and profit coefficients represent the k-th energy type (which can be set according to actual demand and the actual market). Carbon trading costs and profits are calculated as follows: ; and These are the costs and profits of the carbon trading market, respectively. This refers to the carbon trading price coefficient. and This refers to CO2 emissions and emission allowances. The formula for calculating green certificate transaction costs and profits is as follows: ; In the formula, and These are the costs and profits associated with green certificate transactions; The price coefficient for green certificates; The green certificate quota that the community needs to meet; The number of community green certificates.

[0053] ; In the formula, The renewable energy generation quota ratio coefficient in the community energy system; This represents the total electricity demand of the community during the operating cycle. This refers to the total amount of renewable energy generated by the community during the operating cycle.

[0054] Step 4: Based on steps 1 to 3 in Example 2, calculate the system sustainability index values ​​to further quantify sustainability performance.

[0055] To construct a savings rate indicator, the present invention further uses... Figure 2 , 4 Taking the comparison system shown as an example, typical sustainability indicators are listed for illustration: 4.1 Typical system performance indicators, including equipment operating efficiency and system operating efficiency.

[0056] Equipment operating efficiency: ; System operating efficiency: ; 4.2 Typical energy performance indicators, including energy conversion efficiency, renewable energy ratio, and primary energy saving rate.

[0057] Energy conversion efficiency: ; Percentage of renewable energy: ; Primary energy saving rate: ; In the formula, PCE Represents primary energy consumption, calculated from the data in steps 2 and 3 (steps 2 and 3 in Example 2), with subscripts... sys and ref These represent the target system and the comparison system, respectively.

[0058] 4.3 Typical environmental performance indicators, including annual air pollutant emission reduction rates (including global warming potential, acidification potential, and potential impact on human respiratory health).

[0059] ; Let m be the annual emission reduction rate of the equivalent pollutant. To compare the annual emissions of the m-th equivalent pollutant in the system; Let m be the annual emission of the m-th equivalent pollutant in the target system; when m = CO2 - eq., This represents the equivalent annual reduction in carbon dioxide emissions, which is equivalent to the reduction in global warming potential; when m = SO2 - eq., This represents the equivalent annual reduction in sulfur dioxide emissions, which is equivalent to the reduction in acidification potential; when m = PM2.5 - eq., This represents the equivalent annual reduction in inhalable particulate matter emissions, which is equivalent to the reduction in the potential impact on human respiratory health.

[0060] 4.4 Typical economic performance indicators, annual total cost savings rate.

[0061] ; In the formula, ATC This represents the total annual cost.

[0062] In summary, by calculating using the formula, such as Figure 5 It is evident that its sustainability quantitative assessment demonstrates significant effectiveness, specifically: 1) In terms of energy utilization efficiency: the primary energy saving rate reaches 67.21%, effectively improving energy utilization efficiency and reducing dependence on traditional primary energy sources; 2) In terms of environmental emission reduction efficiency: the emission reduction rate of air pollutants is outstanding, significantly reducing environmental pollution (e.g., CO2-eq approximately 74.85%, SO2-eq approximately 53.60%, PM2.5-eq approximately 51.69%), alleviating environmental problems such as global warming and acidification; 3) In terms of economic cost effectiveness: the annual total cost saving rate reaches 54.21%, achieving cost optimization in equipment investment, operation and maintenance, and energy trading, thereby enhancing the system's economic sustainability.

[0063] This invention integrates renewable energy sources such as biomass, solar energy, and geothermal energy, and combines them with the coordinated operation of equipment such as gasifiers, internal combustion engines, organic Rankine cycles, and ground source heat pumps. It demonstrates excellent sustainability in terms of energy conversion, environmental impact, and economic cost, providing a typical demonstration of the technological realization of multi-energy coupled systems.

[0064] Finally, it should be noted that the present invention is not limited to the above embodiments, and many variations are possible. All variations that can be directly derived or conceived by those skilled in the art from the disclosure of the present invention should be considered within the scope of protection of the present invention.

Claims

1. A method for quantitatively assessing the sustainability of an energy system, characterized in that... The method includes the following steps: Step 1: Conduct system identification and feature extraction for the target energy system. System identification identifies the system's architecture, operating mechanism, equipment composition, operating conditions, and operating constraints. Feature extraction, based on system identification, extracts specific data parameters of environmental features, equipment features, and operating features. Step 2: Extract the system's full lifecycle process inventory to determine the direct process inventory data involved in the entire lifecycle from construction and operation to recycling; Step 3: Conduct a quantitative analysis of the system's sustainability footprint. Based on the system's full lifecycle process inventory data, and using years as the time unit, quantitatively demonstrate the system's sustainability performance footprint. Step 4: Based on steps 1 to 3, calculate the system sustainability index values.

2. The method for quantitatively assessing the sustainability of an energy system according to claim 1, characterized in that, Step 2 specifically includes the following sub-steps: Step 2.1: Based on the operation process of the energy system, determine the system input and output parameters, operating parameters, and energy conversion; Step 2.2: Based on the installation capacity of each device obtained in Step 2.1, determine the raw materials, power consumption, investment cost, maintenance cost, and service life of the device. Step 2.3: Based on the amount of raw materials obtained in Step 2.2, calculate the electrical energy consumed and the air pollutants emitted in producing the raw materials; Step 2.4: Based on the data from Steps 2.1 to 2.3, calculate the amount of waste heat and solid waste recovered during system operation, as well as the amount of raw materials recovered after the service ends.

3. The method for quantitatively assessing the sustainability of an energy system according to claim 2, characterized in that, Step 3 specifically includes the following sub-steps: Step 3.1: Raw material consumption and recycling. Determine the initial consumption, recycling amount, and final consumption of each raw material. The calculation formula is as follows: ； in, and Vectors representing the initial consumption, recovery, and final consumption of the five raw materials, respectively; A vector representing the installed capacity of 8 devices; A matrix representing the consumption coefficients of raw materials by the installed equipment; Step 3.2: Energy Flow. Considering the electricity consumption and recovery from raw material production, the electricity consumption during equipment production, and the energy conversion and losses during system operation, the formula for calculating the electricity consumption for raw material production is: ； in, This represents the total electricity consumption for raw material production. Let be the final consumption of the i-th raw material; Here, i represents the energy consumption coefficient of raw materials; N represents the service life of the equipment; the formula for calculating the power consumption of the equipment is: ； in, N represents the total power consumption of the equipment during production; N represents the service life of the equipment. Let j be the installation capacity of the j-th type of equipment; Let be the power consumption coefficient for the j-th type of equipment; the formula for calculating energy conversion and loss during system operation is: ； in, It is the total demand for the k-th type of energy at time t. It is the total production of energy type k at time t; k represents the energy type of cold, heat, electricity, gas, and biomass; G represents the output of the equipment; and the superscripts gen, dem, pc, and sell represent production, demand, purchase, and sale, respectively. Step 3.3: Emissions of six air pollutants, including those from raw material production, equipment manufacturing processes, and energy trading during system operation. The formula for calculating raw material pollutant emissions is: ； The formula for calculating pollutant emissions during equipment production is as follows: ; The formula for calculating pollutant emissions caused by the k-th type of energy trading during system operation is as follows: ； The formula for calculating the total annual emissions of pollutant type n is: ； in, Let n be the total annual emissions of the nth pollutant; The emission of the nth type of pollutant produced from raw materials; The nth type of pollutant emitted during the equipment's production process; Let n be the amount of pollutant emitted at time t resulting from the k-th type of energy trading during system operation. Step 3.4: Emissions of three equivalent pollutants. The six air pollutants are converted into three main equivalent pollutants. The calculation formula is as follows: ； in, Let m be the emission amount of the equivalent pollutant. It is the equivalent conversion factor of the m-th equivalent pollutant for the n-th pollutant; Let n be the emission amount of the nth pollutant; Step 3.5: Process the data from Steps 3.1 to 3.4 through market mechanisms to obtain economic footprint data, including equipment investment and maintenance costs, pollutant tax costs, system operating costs and profits, carbon trading costs and profits, and green certificate trading and profits; The formula for calculating annual investment and maintenance costs is: ； in, Annual investment cost; Annual maintenance costs; This is the maintenance coefficient; This is the return on investment coefficient; Profit margin; Let j be the installation capacity of the j-th type of equipment; The investment and maintenance cost coefficient for equipment type j is given; N is the service life of the equipment; the formula for calculating pollutant tax costs is: ; This is the emission penalty factor for the m-th equivalent pollutant. The formula for calculating energy trading costs or profits during system operation is as follows: ； In the formula, This represents the cost and profit of trading the k-th type of energy; Represents the cost coefficient and profit coefficient of the k-th energy type; Let be the amount of the k-th type of energy purchased at time t; Let be the amount of the k-th type of energy sold at time t; The formulas for calculating carbon trading costs and profits are as follows: ； and These are the costs and profits of the carbon trading market, respectively. This refers to the carbon trading price coefficient. and The emissions and emission allowances for CO2; the formulas for calculating the transaction costs and profits of green certificates are as follows: ; and These are the costs and profits associated with green certificate transactions; The price coefficient for green certificates; The green certificate quota that the community needs to meet; For the number of community green certificates; The renewable energy generation quota ratio coefficient in the community energy system; This represents the total electricity demand of the community during the operating cycle. This refers to the total amount of renewable energy generated by the community during the operating cycle.

4. The method for quantitatively assessing the sustainability of an energy system according to claim 3, characterized in that, Step 4 specifically includes the following sub-steps: Step 4.1: System performance indicators, including equipment operating efficiency and system operating efficiency; the formula for calculating equipment operating efficiency is: ； in, To improve equipment operating efficiency; To output energy to the equipment; Input energy into the equipment; The formula for calculating system operating efficiency is: ； Step 4.2: Energy performance indicators, including energy conversion efficiency, renewable energy share, and primary energy saving rate. The formula for calculating energy conversion efficiency is: ； For system operating efficiency; For energy conversion efficiency; These are the electrical load and heat load requirements, respectively. The sales volumes are for biomass energy, electricity, heat energy, and gas energy, respectively. These are the purchase volumes for solar energy, geothermal energy, biomass energy, electrical energy, thermal energy, and gas energy, respectively. The formula for calculating the proportion of renewable energy is: ； in, The proportion of renewable energy; These represent the production volumes of solar energy, geothermal energy, and biomass energy, respectively. The primary energy saving rate satisfies the formula: ； in, Represents primary energy consumption. To compare the primary energy consumption of the system; This represents the primary energy consumption of the target system, with the subscripts sys and ref representing the target system and the comparison system, respectively. Step 4.3: Environmental performance indicators, including the annual air pollutant emission reduction rate, calculated using the following formula: ； In the formula, Let m be the annual emission reduction rate of the equivalent pollutant. To compare the annual emissions of the m-th equivalent pollutant in the system; Let m be the annual emission of the m-th equivalent pollutant in the target system; when m = CO2 - eq., This represents the equivalent annual reduction in carbon dioxide emissions, which is equivalent to the reduction in global warming potential; when m = SO2 - eq., This represents the equivalent annual reduction in sulfur dioxide emissions, which is equivalent to the reduction in acidification potential; when m = PM2.5 - eq., This represents the equivalent annual reduction in inhalable particulate matter emissions, which is equivalent to the reduction in the potential impact on human respiratory health. Step 4.4: Economic performance indicators, including the annual total cost savings rate, calculated using the following formula: ATCSR is the annual total cost savings rate. To compare the system's total annual cost; The total annual cost of the target system.

5. The method for quantitatively assessing the sustainability of an energy system according to claim 1, characterized in that, The system inputs in step 1 include biomass energy, solar energy, geothermal energy, purchased biomass energy, electricity, gas energy, heat energy, and cold energy; the system outputs include sold biomass energy, gas energy, electricity, heat energy, and cold energy; the system equipment in step 1 includes a gasifier, photovoltaic system, ground source heat pump, improved internal combustion engine, organic Rankine cycle module, heat exchanger, battery, and thermal storage tank.

6. The method for quantitatively assessing the sustainability of an energy system according to claim 2, characterized in that, The input and output parameters for step 2.1 include light intensity, temperature, wind speed, electrical load, heat load, and energy trade volume; the operating parameters include the installed capacity of each device; energy conversion includes energy flow direction and balance, and energy loss; the air pollutants for step 2.3 include CO, CO2, CH4, SO2, and NO. x PM 2.5 .

7. The method for quantitatively assessing the sustainability of an energy system according to claim 3, characterized in that, The three equivalent pollutants in step 3.4 are CO2-eq, SO2-eq, and PM2.

5. 2.5 -eq.

8. The method for quantitatively assessing the sustainability of an energy system according to claim 4, characterized in that, The equipment in step 4.1 that affects equipment operating efficiency includes photovoltaics, gasifiers, internal combustion engines, organic Rankine cycles, ground source heat pumps, thermal storage tanks, electric refrigeration equipment, and gas boilers; the renewable energy sources in step 4.2 include solar energy, biomass energy, and geothermal energy.

9. The method for quantitatively assessing the sustainability of an energy system according to claim 1, characterized in that, Step 4.3 specifies the annual air pollutant emission reduction rate, which targets pollutants including CO2-eq, SO2-eq, and PM2.

5. 2.5 -eq.

10. An energy system, characterized in that, The system includes an energy input unit, an energy conversion unit, an energy storage unit, an energy output unit, and a control unit. These units are sequentially connected and operate collaboratively via an energy transmission path. The energy input unit includes a renewable energy acquisition module and a purchased energy access module. The renewable energy acquisition module contains photovoltaic modules, a biomass feedstock supply device, and a geothermal energy acquisition device. The purchased energy access module is used to connect to purchased electricity and natural gas. The energy conversion unit includes a biomass gasifier, an internal combustion engine, an organic Rankine cycle module, a ground source heat pump, electric refrigeration equipment, and a heat exchanger. The biomass gasifier is connected to the internal combustion engine... Biomass energy is converted into mechanical energy and then into electrical energy. The high-temperature exhaust gas and cylinder liner water from the internal combustion engine are connected to an organic Rankine cycle module to recover energy. A ground source heat pump and a heat exchanger work together to achieve cold / heat energy conversion. The energy storage unit includes a battery, a heat / cold storage tank, and a gas tank, which are used to store electrical energy, cold / heat energy, and biomass gas produced by biomass gasification, respectively. The energy output unit is used to supply electrical energy, heat energy, cold energy, and biomass gas to the outside to meet the end-load demand. The control unit is used to regulate the operating parameters of each unit to ensure energy and power balance, compliant equipment operation, and matching of energy supply and demand timing.

Images