Industrial enterprise energy storage utilization rate calculation method

Abstract

This invention relates to a method for calculating the energy storage utilization rate of industrial enterprises, belonging to the technical field of industrial enterprise energy storage planning. The method first determines the charging / discharging period and the load capacity for each period based on the industrial enterprise's load data from the past year and peak / valley electricity pricing periods. Second, it calculates the actual chargeable / dischargeable capacity of the energy storage for each period based on the basic electricity fee payment method. Finally, based on the energy storage capacity to be calculated, it calculates the actual charge / discharge capacity to obtain the utilization rate of that capacity. This method can accurately calculate the energy storage utilization rate without increasing the user's basic electricity fee, providing an economic basis for owners to invest in energy storage projects or for third-party investment in energy storage projects.

Description

Technical Field

[0001] This invention belongs to the field of energy storage planning technology for industrial enterprises, and relates to a method for calculating the energy storage utilization rate of industrial enterprises. Background Technology

[0002] The construction of energy storage in industrial enterprises is an inevitable trend driven by multiple factors, including the "dual carbon" goals, electricity marketization, enterprises' own needs for cost reduction and efficiency improvement, and the iteration of energy technologies. It is also a key measure for the industrial sector to achieve energy transformation and high-quality development. First, driven by the dual carbon goals and energy transformation requirements, the industrial sector accounts for over 70% of carbon emissions, making it a key area for emission reduction. Simultaneously, the electricity ancillary services market is gradually opening up, and the pricing mechanisms for ancillary services such as peak shaving and frequency regulation are gradually improving. Industrial and commercial energy storage can participate in grid demand response to obtain additional revenue, and the business model is shifting from single arbitrage to a diversified model of "arbitrage + ancillary services + capacity compensation," with some projects already exceeding 12% internal rate of return. Finally, industrial enterprises also need to achieve the dual goals of cost reduction and efficiency improvement as well as power supply security. Industrial electricity costs continue to rise, and high-energy-consuming industrial enterprises account for a significant proportion of their annual electricity expenditure. Energy storage can not only save electricity costs through peak-valley arbitrage but also alleviate the problem of insufficient distribution capacity (such as the long cycle and high cost of transformer expansion), achieving "virtual capacity expansion." Energy storage can also serve as a backup power source, solving problems such as voltage dips and short-term interruptions. Meanwhile, with the widespread adoption of distributed photovoltaic power in industrial enterprises, the contradiction between surplus power generation during the day and power shortage at night has become prominent. Energy storage can absorb surplus photovoltaic power, improve self-consumption rate, and avoid the decline in power generation revenue caused by inverter power limitation. "Photovoltaic + energy storage" has become the core model of industrial green microgrids.

[0003] Therefore, researching methods for calculating energy storage utilization rates in industrial enterprises can accurately determine these rates, providing an economic basis for owner-invested or third-party-invested energy storage projects. This will enhance the economic efficiency and low-carbon development of enterprises, and provide technical support for improving the safe and stable operation and economic benefits of power grids in industrial enterprises. Summary of the Invention

[0004] In view of this, the purpose of this invention is to provide a method for calculating the energy storage utilization rate of industrial enterprises.

[0005] To achieve the above objectives, the present invention provides the following technical solution: A method for calculating the energy storage utilization rate of industrial enterprises, the method includes the following steps: S1. Determine the daily charging and discharging strategy based on peak and off-peak electricity price periods, collect load data for one year according to the preset step size, and calculate the load data for each charging and discharging period of each day. S2. Based on the payment method of basic electricity fees, calculate the remaining chargeable energy storage capacity and the remaining dischargeable energy storage capacity for each charging period and discharge period of each day. S3. Calculate the actual chargeable and dischargeable amount for each charging and discharging period of each day based on the calculated remaining chargeable and dischargeable amount for each charging and discharging period. S4. Based on the energy storage capacity and the nature of the energy storage equipment, calculate the theoretical charge and discharge capacity for each charging and discharging period of each day; S5. Calculate the actual charge / discharge capacity for each charge / discharge period of each day based on the actual charge / discharge capacity for each charge / discharge period and the theoretical charge / discharge capacity for each charge / discharge period. S6. Calculate the actual utilization rate of the energy storage system based on the theoretical charge and discharge capacity for each charge and discharge period and the actual charge and discharge capacity for each charge and discharge period.

[0006] Furthermore, in step S1, load data for one year is collected. Among them, load data The sampling step size is Based on peak and off-peak electricity pricing periods, each day is divided into multiple charging and discharging periods. The daily charging period is denoted as... The discharge period is denoted as ; Count the number of hours for each charging session, and then calculate the load power for each charging session per day. , recorded as :

[0007] In the formula, Indicates the first Charging period The corresponding number of hours, Indicates the first Charging period The first in Hours; Indicates the first Heavenly The load power corresponding to each charging period Take 1, 2, ..., 365; Indicates the first Charging period The first in Hourly load data; Then calculate the load power corresponding to each discharge period separately. , recorded as :

[0008] In the formula, Indicates the first Discharge period The corresponding number of hours, Indicates the first Discharge period The first in Hours; Indicates the first Heavenly The load power corresponding to each discharge period; Indicates the first Discharge period The first in Load data for each hour.

[0009] Furthermore, in step S2, firstly, the capacity for which the basic electricity fee is payable is determined. If the fee is payable based on the transformer capacity, it is recorded as follows: If payment is based on maximum demand, then the maximum load for each month will be calculated separately and recorded as follows: ; Secondly, calculate the remaining chargeable amount for each charging period. , recorded as It is represented as:

[0010] In the formula, Indicates the first Heavenly Remaining chargeable amount during each charging period This represents the load power corresponding to the nth charging period on the kth day; and These represent the transformer capacity and maximum demand, respectively, in kVA. Indicates the load power factor; Finally, calculate the remaining dischargeable amount for each discharge period. , recorded as It is represented as:

[0011] In the formula, Indicates the first Heavenly Remaining discharge capacity during each discharge period Indicates the first Heavenly The load power corresponding to each discharge period.

[0012] Furthermore, in step S3, the first charging period and the first discharging period are defined as the first charge-discharge period, denoted as... The second charging period and the second discharging period are defined as the second charge / discharge period, denoted as . ... and so on, the nth charging period and the nth discharging period are defined as the nth charging / discharging period, denoted as... ; Calculate the actual chargeable / dischargeable amount for each charge / discharge period, expressed as: The calculation method is as follows:

[0013] In the formula, Indicates the first Heavenly The actual charge / discharge capacity during each charge / discharge period.

[0014] Furthermore, in step S4, the theoretical charge / discharge capacity for each charge / discharge period is expressed as follows: The calculation method is as follows:

[0015] In the formula, This represents the theoretical charge / discharge capacity of the stored energy during the nth charge / discharge period on day k. For energy storage installed capacity, Depth of charge / discharge, These refer to the energy storage charging and discharging efficiency, respectively.

[0016] Furthermore, in step S5, the actual charge / discharge amount for each charge / discharge period is recorded as follows: The calculation method is as follows:

[0017] in, This represents the actual chargeable and dischargeable energy storage capacity during the nth charging and discharging period on day k.

[0018] Furthermore, in step S6, the actual utilization rate of the energy storage system is calculated as follows: .

[0019] The beneficial effects of this invention are as follows: First, this invention closely aligns with the actual basic electricity payment methods of industrial enterprises, accurately calculating the actual utilization rate of the energy storage system without increasing the basic electricity cost burden, effectively reducing the enterprise's operating costs. Second, by analyzing the daily and hourly energy storage charging and discharging volumes, this invention provides enterprises with intuitive data support for energy storage configuration, helping them to scientifically and rationally plan the scale and layout of their energy storage systems. Third, this invention provides reliable economic calculation basis for owner-invested or third-party-invested energy storage projects, making investment decisions more informed and improving the project's return on investment. Furthermore, this method helps enterprises achieve their goals of cost reduction, efficiency improvement, and low-carbon development. By optimizing energy storage configuration, it enhances the safe and stable operation of the power grid, reduces carbon emissions, lays a solid foundation for the enterprise's sustainable development, and strengthens the enterprise's competitiveness and adaptability in the electricity market.

[0020] Other advantages, objectives, and features of the invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination, or may be learned from practice of the invention. The objectives and other advantages of the invention can be realized and obtained through the following description. Attached Figure Description

[0021] To make the objectives, technical solutions, and advantages of the present invention clearer, the preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, wherein: Figure 1 This is a schematic diagram of the overall process of the method for calculating the energy storage utilization rate of industrial enterprises according to an embodiment of the present invention; Figure 2 This is a load curve diagram for the past year under an embodiment of the present invention; Figure 3 This is a peak-valley electricity price time period diagram according to an embodiment of the present invention, wherein, Figure 3 (a) is the peak season in summer. Figure 3 (b) is the winter high-pressure period. Figure 3 (c) refers to other periods; Figure 4 This is a load power curve diagram corresponding to each charging and discharging period in the embodiments of the present invention; Figure 5 This is a graph showing the remaining chargeable amount during each charging period in an embodiment of the present invention. Figure 6 This is a graph showing the remaining dischargeable amount during each discharge period in an embodiment of the present invention. Figure 7 This is a graph showing the actual chargeable / dischargeable capacity for each time period under an embodiment of the present invention. Figure 8 This is a graph showing the actual charge and discharge amounts for each time period in an embodiment of the present invention. Detailed Implementation

[0022] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0023] The accompanying drawings are for illustrative purposes only and are schematic diagrams, not actual pictures. They should not be construed as limiting the invention. To better illustrate the embodiments of the invention, some parts in the drawings may be omitted, enlarged, or reduced, and do not represent the actual product dimensions. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0024] In the accompanying drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components. In the description of the present invention, it should be understood that if terms such as "upper," "lower," "left," "right," "front," and "rear" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting the present invention. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0025] Please see Figures 1 to 8 This is a method for calculating the energy storage utilization rate of industrial enterprises.

[0026] Example 1 This embodiment details the specific process of calculating the energy storage utilization rate of industrial enterprises, which includes: Step 1: Determine the daily charging and discharging strategy based on peak and off-peak electricity pricing periods. Combine this with load data from the past year to calculate the load power data for each day, each charging period, and each discharging period.

[0027] First, collect load data for the past year ( ), data step size ( (Not more than 1 hour)

[0028] Secondly, based on peak and off-peak electricity pricing periods, each day is divided into multiple charging and discharging periods, with the daily charging period denoted as... The discharge period is denoted as Count the corresponding hours for each charging period, and record the number of hours for each charging period per day as follows: The number of hours of the discharge period is recorded as .

[0029] Finally: Calculate the load power corresponding to each charging period of the day. , recorded as , Simultaneously calculate the load power corresponding to each discharge period. , recorded as , .

[0030] Step 2: Calculate the remaining chargeable energy storage capacity and the remaining dischargeable energy storage capacity for each day and each charging period, based on the payment method for basic electricity fees.

[0031] First, determine the capacity for which the basic electricity fee will be paid. If the fee is based on the transformer capacity, it will be recorded as follows: If payment is based on maximum demand, then the maximum load for each month will be calculated separately and recorded as follows: .

[0032] Secondly, calculate the remaining chargeable amount for each charging period. , recorded as , recorded as The calculation method is as follows:

[0033] Finally, calculate the remaining dischargeable amount for each discharge period. , recorded as The calculation method is as follows:

[0034] Step 3: Based on the data obtained in Step 2, calculate the actual chargeable / dischargeable amount for each day and each charge / discharge period.

[0035] The actual chargeable / dischargeable capacity is denoted as The calculation method is as follows:

[0036] Step 4: Based on the energy storage capacity to be calculated and the nature of the energy storage equipment, calculate the theoretical charge / discharge capacity for each day and each charge / discharge period. Define the first charging period and the first discharging period as the first charge / discharge period, denoted as... The second charging period and the second discharging period are defined as the second charge / discharge period, denoted as . ... and so on, the nth charging period and the nth discharging period are defined as the nth charging / discharging period, denoted as... .

[0037] Calculate theoretical charge and discharge capacity , recorded as The calculation method is as follows: , In the formula: This represents the energy storage capacity corresponding to the calculated utilization rate. Depth of charge / discharge, These refer to the energy storage charging and discharging efficiency, respectively.

[0038] Step 5: Based on the data from Step 3 and Step 4, calculate the actual charge and discharge amount for each day and each charge and discharge period.

[0039] Calculate the actual charge and discharge amount , recorded as The calculation method is as follows:

[0040] Step 6: Calculate the actual utilization rate of the energy storage system based on the data from Steps 4 and 5.

[0041] Utilization

[0042] Example 2 This embodiment takes a large industrial user in a certain province in China as an example for calculation. The specific execution process is as follows: S1: Calculate the 50MW / 100MWh energy storage utilization rate, collect load data (P) for the past year, with a step size of 1 hour, and the load situation is as follows. Figure 2 As shown.

[0043] S2: According to relevant standard documents, the peak-valley electricity pricing periods are as follows: (1) The time-of-use electricity price for large industrial users is divided into three periods each day: peak, flat, and off-peak. The peak period is from 15:00 to 23:00, the off-peak period is from 11:00 to 15:00 and from 1:00 to 6:00, and the flat period is from 6:00 to 11:00 and from 23:00 to 1:00. The market-based on-grid electricity price is 40% higher than the flat price during the peak period and 60% lower than the flat price during the off-peak period; the transmission and distribution price is 60% higher than the flat price during the peak period and 60% lower than the flat price during the off-peak period.

[0044] (2) Peak electricity prices will be implemented for industrial and commercial electricity during the peak summer (winter) period. The peak hours in July and August are 19:00-21:00 every day, and the peak hours in January and December are 18:00-20:00 every day. The peak electricity price will be 20% higher than the peak electricity price.

[0045] Analysis shows that the peak-valley electricity pricing period consists of two valley periods, two normal periods, and one peak period, making a two-charge, two-discharge charging / discharging strategy suitable. Specific charging / discharging periods are detailed in Table 1.

[0046] Table 1

[0047] S3: Calculate the load power corresponding to each day and each charging and discharging period, where the load power is for the first charging period on day k. Load power during the second charging period Load power during the first discharge period and the load power during the second discharge period For detailed daily data after calculation, please refer to [link / reference]. Figure 4 .

[0048] S4: Payment is based on transformer capacity, main transformer capacity. Take 50MVA.

[0049] S5: Calculate the remaining rechargeable amount for each charging period. The remaining rechargeable capacity during the first charge on day k. and remaining rechargeable power for the second charge The calculation formula is:

[0050] in Use 0.95. For detailed calculations of the remaining rechargeable capacity for the first and second charges each day, please refer to [link / reference needed]. Figure 5 .

[0051] S6: Calculate the remaining dischargeable amount for each discharge period. The remaining dischargeable capacity after the first discharge on day k and the remaining dischargeable capacity after the first discharge The calculation formula is:

[0052] For detailed calculations of the remaining dischargeable capacity after the first discharge each day, please refer to [link / reference]. Figure 6 .

[0053] S7: Calculate the actual chargeable / dischargeable capacity for each charge / discharge period, and the first actual chargeable / dischargeable capacity on day k. and the second actual chargeable / dischargeable capacity The calculation formula is:

[0054] For detailed calculations of the first and second actual charge / discharge capacities each day, please refer to [link / reference]. Figure 7 .

[0055] S8: Calculate theoretical charge and discharge quantities The first theoretical charge and discharge capacity and the second theoretical charge and discharge capacity The calculation formula is:

[0056] in Take 100MWh, It is 0.9. Both are 0.92. The theoretical charge / discharge capacity is calculated to be 106.3 MWh per day per charge / discharge cycle.

[0057] S9: Calculate the actual charge and discharge amounts The first actual charge / discharge charge on day k and the second actual charge and discharge capacity The calculation formula is:

[0058] For detailed calculations of the actual charge / discharge capacity for the first and second charge / discharge cycles each day, please refer to [link / reference]. Figure 8 .

[0059] S10: Calculation utilization rate , 79.12%.

[0060] In addition, the actual utilization efficiency of the system can be calculated under different installed power and number of hours. The calculation results are shown in Table 2. Table 2

[0061] Users or third-party investment companies can calculate the rate of return on energy storage based on the utilization rate of energy storage under different installed capacities, and then select the optimal energy storage installed capacity.

[0062] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A method for calculating the energy storage utilization rate of industrial enterprises, characterized in that: The method includes the following steps: S1. Determine the daily charging and discharging strategy based on peak and off-peak electricity price periods, collect load data for one year according to the preset step size, and calculate the load data for each charging and discharging period of each day. S2. Based on the payment method of basic electricity fees, calculate the remaining chargeable energy storage capacity and the remaining dischargeable energy storage capacity for each charging period and discharge period of each day. S3. Calculate the actual chargeable and dischargeable amount for each charging and discharging period of each day based on the calculated remaining chargeable and dischargeable amount for each charging and discharging period. S4. Based on the energy storage capacity and the nature of the energy storage equipment, calculate the theoretical charge and discharge capacity for each charging and discharging period of each day; S5. Calculate the actual charge / discharge capacity for each charge / discharge period of each day based on the actual charge / discharge capacity for each charge / discharge period and the theoretical charge / discharge capacity for each charge / discharge period. S6. Calculate the actual utilization rate of the energy storage system based on the theoretical charge and discharge capacity for each charge and discharge period and the actual charge and discharge capacity for each charge and discharge period.

2. The method for calculating the energy storage utilization rate of industrial enterprises according to claim 1, characterized in that: In step S1, load data for one year is collected. Among them, load data The sampling step size is Based on peak and off-peak electricity pricing periods, each day is divided into multiple charging and discharging periods. The daily charging period is denoted as... The discharge period is denoted as ; Count the number of hours for each charging session, and then calculate the load power for each charging session per day. , recorded as : In the formula, Indicates the first Charging period The corresponding number of hours, Indicates the first Charging period The first in Hours; Indicates the first Heavenly The load power corresponding to each charging period Take 1, 2, ..., 365; Indicates the first Charging period The first in Hourly load data; Then calculate the load power corresponding to each discharge period separately. , recorded as : In the formula, Indicates the first Discharge period The corresponding number of hours, Indicates the first Discharge period The first in Hours; Indicates the first Heavenly The load power corresponding to each discharge period; Indicates the first Discharge period The first in Load data for each hour.

3. The method for calculating the energy storage utilization rate of industrial enterprises according to claim 2, characterized in that: In step S2, firstly, the capacity for which the basic electricity fee is payable is determined. If the fee is payable based on the transformer capacity, it is recorded as follows: If payment is based on maximum demand, then the maximum load for each month will be calculated separately and recorded as follows: ; Secondly, calculate the remaining chargeable amount for each charging period. , recorded as It is represented as: In the formula, Indicates the first Heavenly Remaining chargeable amount during each charging period This represents the load power corresponding to the nth charging period on the kth day; and These represent the transformer capacity and maximum demand, respectively, in kVA. Indicates the load power factor; Finally, calculate the remaining dischargeable amount for each discharge period. , recorded as It is represented as: In the formula, Indicates the first Heavenly Remaining discharge capacity during each discharge period Indicates the first Heavenly The load power corresponding to each discharge period.

4. The method for calculating the energy storage utilization rate of industrial enterprises according to claim 1, characterized in that: In step S3, the first charging period and the first discharging period are defined as the first charge-discharge period, denoted as . The second charging period and the second discharging period are defined as the second charge / discharge period, denoted as . ... and so on, the nth charging period and the nth discharging period are defined as the nth charging / discharging period, denoted as... ; Calculate the actual charge / discharge capacity for each charge / discharge period, expressed as: The calculation method is as follows: In the formula, Indicates the first Heavenly The actual charge / discharge capacity during each charge / discharge period.

5. The method for calculating the energy storage utilization rate of industrial enterprises according to claim 4, characterized in that: In step S4, the theoretical charge / discharge capacity for each charge / discharge period is expressed as follows: The calculation method is as follows: In the formula, This represents the theoretical charge / discharge capacity of the stored energy during the nth charge / discharge period on day k. For energy storage installed capacity, Depth of charge / discharge, These refer to the energy storage charging and discharging efficiency, respectively.

6. The method for calculating the energy storage utilization rate of industrial enterprises according to claim 5, characterized in that: In step S5, the actual charge / discharge amount for each charge / discharge period is recorded as follows: The calculation method is as follows: in, This represents the actual chargeable and dischargeable energy storage capacity during the nth charging and discharging period on day k.

7. The method for calculating the energy storage utilization rate of industrial enterprises according to claim 6, characterized in that: In step S6, the actual utilization rate of the energy storage system is calculated as follows: 。

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