Experimental study and energy saving analysis of a novel radiant ceiling heating system

In order to have an in-depth understanding of the metal ceiling radiant panel with capillary tubes, a radiant ceiling heating system is constructed to study the actual heating performance and thermal comfort by experiments. In addition, the energy saving potential of the novel heating system is discussed in terms of the COP （coefficient of performance） of the ground source heat pump and the exergy efficiency of the radiant terminal. The results indicate that the heating system shows high thermal stability and thermal comfort. When the system reaches a stable condition, the radiant heat transfer accounts for 62.7% of the total heat transfer, and the total heat transfer can meet the heating demands of most buildings. Compared to a radiant floor heating system, it offers advantages in a shorter preheating time, a lower supply water temperature and a stronger heating capability. The COP of the ground source heat pump is increased greatly when the supply water temperature is 28 to 33 ℃, and the exergy efficiency of the metal ceiling with capillary tubes is 1.6 times that of the radiant floor when the reference temperature is 5 ℃ The novel radiant ceiling heating system shows a tremendous energy saving potential.

Analysis of Power Matching on Energy Savings of a Pneumatic Rotary Actuator Servo-Control System

When saving energy in a pneumatic system,the problem of energy losses is usually solved by reducing the air supply pressure.The power-matching method is applied to optimize the air-supply pressure of the pneumatic system,and the energy-saving effect is verified by experiments.First,the experimental platform of a pneumatic rotary actuator servo-control system is built,and the mechanism of the valve-controlled cylinder system is analyzed.Then,the output power characteristics and load characteristics of the system are derived,and their characteristic curves are drawn.The employed air compressor is considered as a constant-pressure source of a quantitative pump,and the power characteristic of the system is matched.The power source characteristic curve should envelope the output characteristic curve and load characteristic curve.The minimum gas supply pressure obtained by power matching represents the optimal gas supply pressure.The comparative experiments under two different gas supply pressure conditions show that the system under the optimal gas supply pressure can greatly reduce energy losses.

Interaction of ions in water system containing copper-zinc alloy for boiler energy saving

Copper-zinc alloy element for boiler energy saving was put in the intake of simulated boiler system to investigate the interaction and transfer of ions in water system both theoretically and experimentally.The fouling was analyzed by scanning electron microscopy(SEM)and energy dispersive X-ray detector(EDX).The results show that the transfer of calcium and magnesium ions in heat-transfer-surface-water system is affected by zinc ions dissolved from the alloy because of primary battery reaction.Some calcium ions of calcium carbonate crystal are replaced by zinc ions,the growth of aragonite crystal nucleus is retarded,and the transition of calcium carbonate from aragonite to calcite is hampered.

ENERGY-SAVING MATCHING STRATEGY AND EXPERIMENTAL STUDY OF PUMPING SYSTEM FOR TRUCK-MOUNTED CONCRETE PUMP

Aiming at the high fuel consumption and use-cost of truck-mounted concrete pump , an energy-saving matching strategy of pumping system is presented and the experimental study is conducted.Since pumping system occupies most resources of engine , the matching strategy between engine and main pump is analyzed to meet the load demand and reduce the engine rational speed drop.The testing method is established to measure the fuel consumption of engine under various working conditions , and the experimental data are analyzed to find the law of the fuel consumption of engine.The system performance can be improved by adjusting the system input value.Finally , the energy-saving matching strategy is established to reduce the fuel consumption of truck for unit workload , which provides a new approach for the energy-saving of truck-mounted concrete pump.

Research of Supercapacitor Voltage Equalization Strategy on Rubber-Tyred Gantry Crane Energy Saving System

A model for supercapacitor voltage equalization strategy is analyzed, and on this basis a supercapacitor voltage equalization method for Rubber Tyred Gantry Crane (RTG) energy saving system is proposed, namely active voltage equalization method based on Buck-Boost converter. The equalizing speed of the proposed method is fast. Firstly, the working principle and process of the voltage equalization circuit is analyzed in detail. In addition, design of active voltage equalization circuit parameters and control strategy are given. Finally, simulation analysis of the series connection of supercapacitors module is performed. Results show that this method for equalizing voltage can avoid over-voltage of each cell and possess practicable and high value for supercapacitor RTG energy saving system.

Design of Energy Saving Lighting System in University Classroom Based on Wireless Sensor Network

In order to reach the objective of intelligence and energy saving for university classroom lighting, energy saving lighting control system in university classroom based on wireless sensor network is designed, including design of sensor node and sink, as well as corresponding development of control program and upper-computer software. The system sets single-chip Ameg16 as control center, realizes communication between nodes via nRF24L01 wireless transceiver module, and realizes communication between sink and upper computer via w5100 wireless internet module. It perceives illumination intensity via photoconductor, detects the human body position via infrared pyroelectric sensor, and places the sensor node on the lamp, so the light can be controlled according to position of human body and current illumination intensity, which can realize energy saving to a large extent on condition that lighting requirement is satisfied. The system has low cost, and there is no need to change the original lighting circuit. The light can be turned off by hand, and when multi-media are used for the class, light can keep off even it is dim. In addition, this system has the function of automatic fault report, which is convenient for property maintenance.

Control performance and energy saving of multi-level pressure switching control system based on independent metering control

Aiming at the problem of large energy consumption in hydraulic control system with large load and variable working conditions,based on the multi-level pressure switching control system(MPSCS),a multi-level pressure switching control system based on independent metering control is proposed combined with the independent metering control technology.The configuration principle of the system is given,the mathematical model of this system is established,and the control strategy of the system under 4 different working quadrants is put forward.Finally,the control performance and energy saving characteristics of the system are tested.The test results show that the switching of high and low pressure power supply has a certain effect on the response of step position and ramp position under impedance working condition.The displacement curves show slow climbing or abrupt change of ramp position,and the position accuracy is less than 1 mm.The multi-level pressure switching control system based on independent metering control can recover and store energy under the transcendence working conditions.The control accuracy is about 1 mm,and the energy recovery rate is about 70%~80%.

Case Studies of Energy Saving and CO₂Reduction by Cogeneration and Heat Pump Systems

This paper describes two case studies: 1) a cogeneration system of a hospital and 2) a heat pump system installed in an aquarium that uses seawater for latent heat storage. The cogeneration system is an autonomous system that combines the generation of electrical, heating, and cooling energies in a hospital. Cogeneration systems can provide simultaneous heating and cooling. No technical obstacles were identified for implementing the cogeneration system. The average ratio between electric and thermal loads in the hospital was suitable for the cogeneration system operation. An analysis performed for a non-optimized cogeneration system predicted large potential for energy savings and CO2 reduction. The heat pump system using a low-temperature unutilized heat source is introduced on a heat source load responsive heat pump system, which combines a load variation responsive heat pump utilizing seawater with a latent heat-storage system (ice and water slurry), using nighttime electric power to level the electric power load. The experimental coefficient of performance (COP) of the proposed heat exchanger from the heat pump system, assisted by using seawater as latent heat storage for cooling, is discussed in detail.

Summary of Steam System Optimization and Energy Saving and Carbon Reduction Practice in Yanshan Petrochemical Company

This paper analyzes the main problems of Sinopec Beijing Yanshan Petrochemical Co.,Ltd.,such as decentralized steam system layout,many types of fuels,obvious increase in fuel cost,low operation efficiency of turbine and boiler and high self consumption loss,and puts forward and implements optimization and improvement measures such as pressure raising transformation of natural gas system,adjustment of energy consumption structure,reduction of energy consumption cost,improvement of steam production quality and equipment efficiency.The results showed that compared with the fuel consumption in 2018,the consumption of coal coke was reduced by 550000 t,the consumption of natural gas was increased by 170000 t,and the total consumption of fuel gas and fuel oil was increased by 50000 t,equivalent to 246000 t of standard coal;the purchased electricity was increased by about 5×10^(8) kW·h.Green power trading and 14.76 MW distributed photovoltaic projects were carried out.According to the calculation of 1400-1600 h annual power generation in class II photovoltaic areas and the emission factor of North China regional power grid baseline,the annual emission reduction was about 55000 t CO_(2) in 2021.After the above transformation,the goal of zero-coking is achieved;the steam consumption of units is reduced by 21.5%,the steam production of boilers is reduced by 24.9%,and the annual emission reduction is about 760000 t CO_(2),which has achieved good results.

Construction practice of market system for energy saving renovation of existing buildings

The energy-saving reconstruction market of existing buildings is a complex system.It includes three subsystems:service market,capital market and technology market.The service market takes the relationship between energy service companies and owners as the core to establish service associated relationships.The capital market is based on the mechanism of"investment guarantees and risk sharing"to form structures of the capital market.The technology market relies on the"industry-university-research"mode to build technology supporting platforms.Being interdependent and mutually restricted,the three subsystems form the complete system of existing buildings in energy-saving reconstruction.

Design of Weigh Feeder Control System for Energy Saving Using Performance-Adaptive Method

This paper discusses a design method for the control system of a weigh feeder that supplies powder and granular material at a constant rate. Most weigh feeders employed in industry are controlled by proportional and integral （PI） compensation, and the control performance is decided by the selection of parameters. To attain advanced control performance by PI control, the PI parameters are designed on the basis of generalized minimum variance control （GMVC）. In this study, to achieve user-specified control performance by GMVC-based PI control, the design parameters of GMVC are automatically adjusted using a performance-adaptive method. The control performance discussed in this study consists of the variance of the control error and that of the difference in the control input. In a conventional performance-adaptive method, the variance of the control error is reduced. In this study, to reduce energy consumption and to achieve user-specified control performance, the variance of the difference in the control input is specified and the design parameter is determined. To demonstrate its effectiveness, the proposed method is applied to an actual weigh feeder.

Energy-saving potential analysis for teaching building with intermittent heating system in university of Tianjin

An energy consumption analysis based on the heating characteristic of a building with central heat exchanger in a university of Tianjin was done,and the feasibility of intermittent heating with variable speed pumps was discussed. By comparing various methods of energy consumption analysis,a modified Bin method based on the weather data in Tianjin was adopted. The heat consumption of the buildings under intermittent heating mode was calculated and compared with continuous heating mode,the result shows that intermittent heating can reduce energy consumption for 1 941 759 kW·h,save standard coal for 341 t,and reduce pump power consumption for 72 679 kW·h annually. Intermittent operation by means of varying the pump frequency not only leads to savings in fuel consumption and reduction in pollutant emissions,but also reduces operating costs significantly and it is an ideal energy-saving method. By analyzing the results,the recommendations of heating operation regulation and the transformation of pipe network were proposed separately to different kinds of buildings in colleges,such as laboratory building,teaching building.

Analysis of Energy Saving Achievable through Solar Photovoltaic Systems on School Roofs： A Case of the City of Rome

Embracing renewable energy technology makes a lot of sense for the public sectors and schools as it meets the government sustainability goals and provides a financially viable means of achieving carbon savings while offering income potential. This study is aimed to quantify the achievable energy saving by spread use ofphotovoltaic systems on public building stock in the city of Rome. The installation of PV （photovoltaic） systems in the historic center depends on the feasibility conditions, generally more complex compared to the cases examined in the consolidated city, because they require compliance with the formal and aesthetic characteristics of the buildings, so the choice must be made between compatible components, which allow to minimize the transformation. The suburbs are characterized by large plane roofs in bad conditions and belonging to isolated buildings, so the useful surface, according to shading condition, offers a big potential for renewable technologies. The research provides an evaluation of maximum production of solar energy and the subsequent energy saving and reduction of greenhouse gasses, using parametric data, and an evaluation of the cost-effectiveness, with a rough calculation of return on investment.

Research on Energy Saving Technology of Load Sensitive Variable Steering System for Vehicles

In view of the large energy loss problem in the traditional full hydraulic steering system,a scheme of replacing the ordinary pump with the priority valve with the load sensitive variable pump is proposed to make the variable pump provide the corresponding flow rate according to the needs of the steering system to achieve the purpose of energy saving.Through the establishment of the system AMESim simulation model,the data comparison shows that the energy loss of the load sensitive variable steering system is significantly reduced relative to the traditional full hydraulic steering system.

Application of the waste heat recovery system and energy-saving in the strip continuous annealing furnace

The common problem of cold strip continuous annealing furnaces is high exhaust gas temperature and great energy consumption. Taking the cold-strip continuous annealing furnaces of Baosteel No. 4 cold mill plant as an example, several waste heat recovery systems in the annealing furnaces are compared and their advantages and disadvantages are analyzed through different energy-saving technologies.

Strategies for Introducing Energy Saving Idea into Residential Planning and Design in Urban and Rural Areas of China

Currently,energy saving design has been conducted on single building but not on the whole residential community in urban and rural areas.So,the paper has proposed energy saving measures for residential planning from the perspective of site selection and layout of buildings.Specific measures are as follows.Firstly,buildings should be constructed on the sunny side and leeside;secondly,buildings on the south should be lower than those on the north;the east side of the building should be open while the west side should be closed;thirdly,climate protection unit should be set;fourthly,buildings should be of northsouth direction primarily,and the main room should be set on the east side and the assistant rooms or passage on the west side in the buildings of east-west direction;fifthly,it should select compact and wellarranged households and the units should not be combined in point and dislocation and jointing.

The Efficiency of the Energy Saving Stoves in Amboseli Ecosystem-Analysis of Time, Energy and Carbon Emissions Savings

It is estimated that more than 2.5 billion people worldwide use biomass for cooking. Burning biomass is one of the major contributors to carbon dioxide (CO2) emission—a principle gas in global warming and climate change. One way of cutting down the CO2 emissions is adaptation of efficient and clean energy technologies. This study examined the efficiency of the energy saving stoves in Amboseli ecosystem by comparing the cooking time, energy use, wood fuel and carbon emissions to the traditional three stone open fire set ups. The result indicates a statistical difference in the time spent cooking on energy stoves and three stone open fire (t = 5.3055;n = 60;p = 0.00117). Energy saving stoves saved 12.7% - 33.3% of wood fuel compared to the traditional three stones set ups. Water boiling tests to determine the energy savings, revealed that energy saving stoves saved between 25.74% and 26.16% energy/joule per session in-house and outdoor settings respectively. Based on the two meals prepared per day by each household, the total Carbon Emission Savings for the 1000 local beneficiaries of energy saving stoves varied from 102,200 kg CO2 (indoor cooking) to 357,700 kg CO2 (outdoor cooking) per year. It is therefore concluded that energy saving stoves saves time, fuel wood and energy, and reduces carbon emissions. The study findings refute the claims that open fire when carefully operated can be fuel efficient and clean burning to rival energy saving stoves. To improve the performance of the energy saving stoves, it is recommended that a design modification be done to include a chimney to emit excess smoke during indoor cooking;and the stove should be fixed to the floor with mortar to minimise heat loss and breakages.

Energy saving analysis of a hybrid ground-coupled heat pump project

A hybrid ground-coupled heat pump（HGCHP）project in Nanjing,China is chosen to analyze the building energy-consumption properties in terms of different control strategies,building envelope and the terminal air-conditioning system.The HGCHP uses a supplemental heat rejecter to dissipate extra thermal energy to guarantee underground soil heat balance.The software EnergyPlus is employed to simulate the project and design the heat flow of the cooling tower and the borehole heat exchanger（BHE）.Then two feasible control strategies for the cooling tower and the borehole heat exchanger are proposed.The energy-saving potential of the building envelope is analyzed in terms of the surface color of the wall/roof.With the same terminal system,it is found that in the cooling season the heat flow of the insulated building with black wall/roof is 1.2 times more than that with white wall/roof.With the same insulated building and gray wall/roof,it is concluded that the heat pump units for a primary air fan-coil system show an annual energy consumption increase of 44.7 GJ compared with a radiant floor system.

Optimum Energy Management of the Central Air-Conditioning System in Intelligent Buildings

An optimum energy saving scheduling strategy of the central air conditioning system in an intelligent building (IB) was proposed. Based on the system analysis a set of models of the central air conditioning system was established. The periodically autoregressive models (PARM) based on genetic algorithms (GA) were used to predict the next day’s cold load. The improved genetic algorithms (IGA) with stochastic real number coding were used to finish the optimum energy saving scheduling of the system. The simulation results for the building of the Liangmahe Plaza show that the proposed strategy can save energy up to about 24 5%.

Low-carbon and Energy-saving Designs Preserving Primitive Ecological Conditions——With the Planning of Ancient Banyan Park in Mengshan County,Guangxi,China as a Case Study

It was proposed that park planning should be based on local economic development,should focus on the preservation of primitive ecological conditions and the application of low-carbon and energy-saving concepts.The planning of Ancient Banyan Park in Mengshan County by following the principles of respecting local history and culture,improving functions and supporting facilities,human-centered,overall planning and all-around consideration,respecting characteristics of the local area(the planning site),satisfying operation requirements of the park,applying low-carbon and energy-saving concepts,and avoiding over-engineering,aimed at protecting natural images of the park,primitive history,culture and characteristics of the local area and providing a space for local residents' various activities.Modern aesthetic forms were combined,cultural connotation of natural environment stressed to build a landscape space system of the Ancient Banyan Park that matches well with environment of the planning site.The park was designed into 4 functional areas:sport area,fitness plaza area,garden recreational area and ancient banyan cultural area.Different functions of these subareas were taken into consideration to create conservation-minded garden landscapes which were both independent and unified.