Interpretation of Jianke [2008] No. 114 document on ACREL-5000 energy consumption monitoring system based on electric energy sub-item measurement

Shanghai Ankerui Electric Co., Ltd. Foreword In response to Jianke [2008] No. 114 document, combined with our company's many years of experience in power meter manufacturing, this paper discusses an energy consumption monitoring system selection scheme that meets the requirements of electric energy sub-item metering in Jianke [2008] No. 114 document for readers' reference.

1. Background

On January 3, 2008, the Beijing Municipal Construction Committee and the Municipal Development and Reform Commission announced the average electricity and water consumption of some state agency office buildings and large public buildings in Beijing that implemented energy audits in 2007. Among them, the state agency office buildings of the 20 units audited had an average annual electricity consumption of 85.4 kWh per square meter of building area, and an annual per capita electricity consumption of 3072.5 kWh. Large public buildings consume 3 to 5 times more electricity than ordinary buildings. The annual electricity consumption of state agency office buildings and large public buildings accounts for about 22% of the total urban electricity consumption in China, and the annual electricity consumption per square meter is 10 to 20 times that of ordinary residential buildings. It is 1.5 to 2 times that of similar buildings in developed countries such as Europe and Japan. The annual electricity consumption per square meter of large public buildings in Beijing is between 50 and 300 kWh, which is 3 to 5 times higher than that of ordinary buildings. At present, there are about 500 million m2 of large public buildings in my country. The electricity consumption is 70 to 300 kWh/m2*year, which is 10 to 20 times that of residential buildings, and is a high-density area of ​​building energy consumption. The survey results show that this type of building still has a serious problem of energy waste and has great potential for energy saving. (Source: China.com)

2. Government Guidance Documents The State Council Decree No. 531 of the People's Republic of China, signed by Premier Wen Jiabao, "Regulations on Energy Conservation in Public Institutions", came into effect on October 1, 2008. Article 14 of the "Regulations" clearly states that public institutions should implement an energy consumption metering system, distinguish energy consumption types and energy consumption systems, implement energy consumption metering by household, category and item, and monitor energy consumption status to promptly discover and correct energy waste. Local governments have also issued relevant regulations, such as: "Notice of the Shanghai Municipal Construction and Transportation Committee on Further Strengthening the Management of Professional Energy-Saving Design Technology for Civil Building Equipment in the City" - Shanghai Construction and Transportation [2008] No. 828; "Regulations on Energy Measurement Design of Public Buildings in Jiangsu Province" - Su Jianke [2007] No. 217; Su Jianke [2007] No. 217 stipulates that from September 1, 2007, new construction, reconstruction and expansion of public building projects with a single unit area of ​​more than 20,000 m2 should comply with relevant national and provincial standards during design and construction drawing review. In the electrical part, it is clearly stipulated that each outgoing line circuit of the substation should be equipped with an energy metering device, and the metering device should adopt a digital energy meter. According to the type and grade of the building, a communication interface should be configured as much as possible to facilitate the formation of a network and set up a management background. Shanghai Construction and Transportation [2008] No. 828 stipulates that from January 1, 2009, large public buildings with a single building area of ​​more than 20,000 square meters, office buildings of state organs at the municipal (district) level, and building energy conservation demonstration projects applying for the state and the city shall be equipped with energy consumption monitoring systems in accordance with the requirements of the "Technical Guidelines". On June 24, 2008, the Ministry of Housing and Urban-Rural Development issued the "Notice on Issuing the Technical Guidelines for the Construction of Energy Consumption Monitoring Systems for State Organs and Office Buildings and Large Public Buildings", namely the document "Jian Ke [2008] No. 114", which requires the Construction Departments of all provinces and autonomous regions, and the Construction Committees (Construction Bureaus) of municipalities directly under the Central Government and cities with independent planning status to follow and implement it. Document [2008] No. 114 contains the following annexes: Annex 1: Technical Guidelines for Itemized Energy Consumption Data Collection Annex 2: Technical Guidelines for Itemized Energy Consumption Data Transmission Annex 3: Technical Guidelines for Itemized Building Metering Design and Installation Annex 4: Technical Guidelines for Data Center Construction and Maintenance Annex 5: Construction, Acceptance and Operation Management Specifications

3. Interpretation of technical guidelines

3.1 Building Objects Document No. 114 divides state office buildings and large public buildings into eight categories based on the use functions and energy characteristics of the buildings. They include office buildings, shopping mall buildings, hotel and restaurant buildings, cultural and educational buildings, medical and health buildings, sports buildings, comprehensive buildings, and other buildings. Other buildings refer to state office buildings and large public buildings other than the above seven types of buildings.

3.2 Energy consumption data collection indicators

3.2.1 Classified energy consumption According to the building energy consumption category, there are 6 classified energy consumption data collection indicators, including: electricity consumption, water consumption, gas consumption (natural gas or coal gas), central heating heat consumption, central cooling cooling consumption, and other energy applications, such as central hot water supply, coal, oil, renewable energy, etc.

3.2.2 Electricity consumption by item In the energy consumption classification, electricity should be divided into 4 items, including lighting socket electricity, air conditioning electricity, power electricity and special electricity. The 4 items of electricity are mandatory. Lighting socket electricity includes: lighting and socket electricity, corridor and emergency lighting electricity, outdoor landscape lighting electricity; air conditioning electricity includes: hot and cold station electricity, air conditioning terminal electricity; power electricity includes: elevator electricity, water pump electricity, ventilator electricity; special electricity includes: information center, laundry room, kitchen restaurant, swimming pool, gymnasium, other special electricity.

4. Measuring device

4.1 Metering device - Incoming circuit electric energy metering should be reasonably set up with sub-item metering circuits. Its sub-item metering system should use electronic active energy meters with an accuracy level of 1.0 or above (0.2, 0.5, 1.0). The ordinary energy meter used should be composed of a measuring unit and a data processing unit, and can display, store and output data, and have a standard communication interface. A multi-function energy meter should be installed at the main incoming line on the low-voltage side of the transformer (AC230/400V), which should at least have the functions of monitoring and measuring three-phase current, voltage, active power, power factor, active energy, maximum demand, total harmonic content and 2-21 harmonic components. ACR320ELH power meter is selected. The meter has the following functions: full power measurement (U, I, P, Q, PF, F, S); THDu, THDi, 2-31 harmonic components; maximum demand (I, P), four-quadrant power measurement, multi-rate power accumulation; voltage crest factor, telephone waveform factor, current K factor, voltage and current imbalance; grid voltage and current positive, negative, and zero-sequence component measurement; 4DI+3DO, RS485 interface, Modbus-RTU and other functions. Figure 1 ACR320ELH meter

4.2 Metering device - other circuits In the "4 Design Regulations" of the Technical Guidelines for Design and Installation of Sub-item Metering of Buildings, "Sub-item metering circuits should be reasonably set up, and sub-item metering meters should be set up for the following circuits": (1) transformer low-voltage side outgoing line circuit; (2) separately metered external power supply circuit; (3) special area power supply circuit; (4) refrigeration unit main power supply circuit; (5) separately powered cold and hot source system auxiliary pump circuit; (6) centrally powered split air conditioning circuit; (7) lighting socket main circuit; (8) elevator circuit; (9) other power consumption circuits that should be separately metered. Figure 2 ACR220EL meter ACR120EL or ACR220EL power meter is selected. The meter has the functions of three-phase current, voltage, power, power factor, and electric energy measurement, with RS485 interface, Modbus protocol, etc.

4.3 Metering device - terminal energy accumulation

4.3.1 For dormitories, shops, wards and other places that should be measured to economic accounting units, DDS1352 or DDSF1352 meters can be used; DDS1352 single-phase meters are used, DIN35mm rail installation, width is 1 module (i.e. width is 18mm), the maximum single-phase current connected at one time is 30A, and the accuracy is 1.0. The advantages are small size and low price, but it cannot be networked. DDSF1352 single-phase meters are used, DIN35mm rail installation, width is 4 modules, the maximum single-phase current connected at one time is 80A, the accuracy is 1.0, with RS485 interface, Modbus protocol or DL/T645 protocol, and can be networked.

4.3.2 For electricity facilities, separate metering shall be carried out according to the electricity consumption of walls and sockets, power consumption, air conditioning consumption, and special electricity consumption. When school classrooms, medical wards, and hotel rooms are measured by floor or functional area, DTSF1352 or ACR120EL meters can be selected. The DTSF1352 three-phase four-wire meter is installed on a DIN35mm rail with a width of 7 modules. It can be installed in a lighting box or a power box. The maximum three-phase current connected at one time is 80A, which can be collected through a current transformer. The accuracy is 0.5 level, with Modbus protocol or DL/T645 protocol, and can be networked. Figure 3 DDS1352 meter

5. Data Transfer

5.1 Data Collector The data collector is a device that collects information about electric energy or other energy consumption in a region. It collects, processes and stores information about various meters under its jurisdiction through channels, and exchanges data with the data center through remote channels.

5.2 Data Transfer Station In order to reduce the server load of the data center and optimize the network transmission efficiency, a data transfer station is set up. The data transfer station collects and caches the energy consumption data of the monitored buildings in its management area and forwards it to the upper-level data center in full. The data transfer station is not responsible for the processing and handling of the data, and may not store the data permanently.

5.3 Data Center The data center collects and stores the energy consumption data of the monitored buildings within its management area, and processes, analyzes, displays and publishes the energy consumption data within the area. Data centers are generally located at the ministerial level, provincial (autonomous region, municipality) level and in cities with a large number of monitored buildings. Data centers other than ministerial level should upload various classified summary data to the ministerial data center step by step. Figure 4

6.Acrel-5000 system structure

The power management system uses computers, communication equipment, and metering units as basic tools, providing a basic platform for real-time data collection, remote management, and control of large public buildings. It can form a complex monitoring system with detection and control equipment. The system mainly adopts a hierarchical distributed computer network structure, with substation control management layer, network communication layer, and field equipment layer. (As shown in the figure) Figure 57. Acrel-5000 data upload mode Figure 68. Acrel-5000 data encoding rules Figure 7 The encoded energy consumption data consists of 15-bit symbols. If a certain code is not required for a certain project, the corresponding number of bits is replaced by "0". Example: Beijing International Studies University Library air conditioning electricity consumption 110100D10101B20110100: administrative division code, 110100 Beijing Municipal District D: building category code, D cultural and educational building 101: building identification code, uniformly stipulated by the county and city construction administrative department where the building is located, 101 library Beijing International Studies University Library 01: classification energy consumption code, 01 electricity B: sub-item energy consumption code, A lighting socket electricity, B air conditioning electricity, C power electricity, D special electricity 2: first-level sub Item, 2 Air conditioning terminal 0: Secondary sub-item, 0 means no such item 9. Acrel-5000 energy consumption data processing The total energy consumption of the building is the sum of the standard coal volume converted from the energy consumption of each category of the building (except water consumption); Total electricity consumption = ∑ direct measurement value of each transformer total meter; Classified energy consumption = ∑ direct measurement value of each classified energy consumption meter; Sub-item electricity consumption = ∑ direct measurement value of each sub-item electricity meter; Electricity consumption per unit building area = total electricity consumption/total building area; Electricity consumption per unit air-conditioned area = total electricity consumption/total air-conditioned area. Classification Energy and Standard Coal Conversion Table No. Energy Type Standard Coal/Energy 1 Electricity 1229 kg/10,000 kWh 2 Gas (natural gas) 12143 kg/10,000 m3 3 Gas (coke oven gas) 5714~6143 kg/10,000 m3 4 Gas (other gas) 3570 kg/10,000 m3 5 Central heating 1229 kg/million kilojoules 6 Coal 0.7143 kg/kg 7 Liquefied petroleum gas 1.7143 kg/kg 8 Gasoline 1.4714 kg/kg 9 Kerosene 1.4714 kg/kg 10 Diesel 1.4571 kg/kg 10.Acrel-5000 Energy Consumption Data Display The data center receives and stores data uploaded by monitoring buildings and data transfer stations within its management area, and processes, analyzes, displays and publishes energy consumption data within its management area. The data center is divided into ministerial data center, provincial (autonomous region, municipality) data center and municipal data center. Municipal and provincial (autonomous region, municipality) data centers should upload various classified energy consumption summary data step by step. The ministerial data center will classify and summarize the energy consumption data reported by the provincial (autonomous region, municipality) data centers to form national classified energy consumption summary data, and publish national and provincial (autonomous region, municipality) energy consumption data statistical reports and various classified energy consumption summary tables. The display of monitored building data should include: (1) basic information of the building, energy consumption monitoring status, energy consumption classification and sub-item status; (2) hourly original reading list of each monitoring branch; (3) hourly, daily, monthly and annual energy consumption values ​​of each monitoring branch (list and graph); (4) various relevant energy consumption index graphs and tables; (5) comparison of relevant energy consumption indicators of a single building with similar reference buildings (such as benchmark values, average values, etc.) (list and graph). Figure 811. Application of new technology - based on zigbee wireless meter reading technology ZigBee is an emerging short-distance (100m--2000m), low power consumption, low data rate (20k--250kbps), low cost (relative to the charges of GPRS network), and low complexity wireless network technology. ZigBee technology has incomparable application advantages in terms of low power consumption, low cost and networking capabilities. Figure 9 The network with MESH mesh network topology has powerful functions. The network can communicate through "multi-level jump"; this topology can also form an extremely complex network; the network also has self-organization and self-healing functions. Zigbee technology electric meter remote meter reading system Figure 10 Remote meter reading based on zigbee technology eliminates the trouble of arranging communication lines on site, saves costs and reduces the amount of engineering, which greatly facilitates the effective realization of centralized management of electric energy; the use of mesh network structure fully guarantees the reliability of data transmission. Zigbee technology meter reading demonstration system illustration Figure 1112. Typical projects Acrel-5000 energy consumption monitoring and electricity sub-item metering system has been widely used in key projects such as Beijing Municipal People's Government Office Building, Taizhou Administrative Center, Dalian Futures Trading Building, China Ocean University Gymnasium, Shanghai World Expo venues, Pudong Library, Shanghai Pudong Airport, Daqing Airport, Guangzhou New TV Station, Shanghai Huawei Base, Huashan Hospital, etc.