Analysis Of Energy Savings Research Articles

Analysis of Energy Savings and CO2 Emission Reduction Contribution for Industrial Facilities in USA

Abstract Energy audits can identify energy consumptions, energy costs of the facility and evolve to develop measures to maximize efficiency, optimize supply energy, and eliminate waste. This paper investigates the potential energy savings at 20 different industrial sectors with 152 assessments for various facilities in Wisconsin, USA. On average, eight energy recommendations were suggested and applied in each facility. This paper provides a detailed guideline for each industry in terms of eight different energy categories: heating, ventilation, and air conditioning (HVAC) systems, heat recovery systems, electrical demand management, and utility bills, motors, compressors, waste management, and productivity enhancement, lighting, besides building envelope. In total, the energy savings were as follows: 98 million kWh in the shape of electricity, 561 billion British thermal units (BTUs) gas savings, 44 million gallons water savings, and 2-million-pound solid waste savings. Based on these savings, a 100-thousand-ton reduction in carbon dioxide emissions was obtained.

Analysis of energy consumption and potential energy savings of an institutional building in Malaysia

The building sector is one of the major energy users and greenhouse gasses emitter. An energy audit is one of the effective approaches to identify efficient energy usages and energy savings. A details walk-through energy audit has been conducted to analyse the energy consumption pattern and potential energy conservation opportunities (ECOs) in Research and Development (R&D) building at Universiti Malaya from March to May 2017. Eight different appliances were categorised to analyse and the audit results were verified with the building’s utility bill which on average were between 160 MWh to 250 MWh and RM 80 k to RM 120 k per month. In this case, it was found that the air-conditioning (34%), lighting (18%) and PC/laptops (10%) are the main appliances that contributed to the total energy consumption for the building. The replacement to LEDs light in three different stages marked as Level A, Level A + B and Level A + B + C revealed to be a good solution for energy conservation which resulted in annual energy savings of 72,750 kWh, 110,381 kWh and 144,386 kWh. It concurrently contributes to annual savings of RM26554, RM40289 and RM52701 based on 9 h daily operating time with the payback period of about 1 year.

Study of Energy Saving Analysis for Different Industries

Abstract This study analyzes the energy consumption and saving performance in the industries in the U.S.A. All energy assessments implemented were for facilities whose annual energy consumptions were less than 9,000,000 kWh (small- and medium-sized industries) that belong to the manufacturing industries with Standard Industrial Classification (SIC) codes ranging from 2000 to 3999 in addition to SIC codes starting with 49. In this study, assessments are classified based on the SIC codes with recommendations analysis for each classification to get a better idea of what recommendations were suggested in each major industrial sector, knowing that 68 assessments were made, and their SIC ranged from 14 to 49. In addition, this study could be considered as a guide for energy engineers and other personnel involved in the energy assessment process. The information investigated can give a better prediction for composing better energy-demanding industries and minimizing energy consumption. More than 61 energy assessments were conducted for manufacturing facilities and analyzing the data gathered and processed. Through the research, the Fabricated Metal industry achieved the highest average kWh savings and cost savings within the industries studied in this study. According to the average gigajoule (GJ) savings, the fabricated metal industry ranked second within the studied industries. Conversely, Food and Kindred Products achieved the highest GJ energy savings within the studied industries. Lighting, motors, compressors, and heating, ventilation, and air conditioning (HVAC) were the most contributing industries in a total of 547 recommendations.

Geometric Analysis of Energy Saving for Directional Charging in WRSNs

Wireless power transfer (WPT) enables a reliable and convenient charging paradigm. This article concerns the fundamental issue of energy saving in wireless rechargeable sensor networks (WRSNs), i.e., given a fixed number of rechargeable sensors (RSs) with their locations and charging demands, we focus on a minimal charging expenditure (MAP) problem with directional WPT to decrease the energy expenditure of the charger, on condition that the charging demands of all sensors are satisfied. In particular, we consider the anisotropic energy receiving property of RSs, which is closely related to the distance and the angle between the sensor and the charger antenna's orientation in directional WPT. We transform the MAP problem into an optimal function placement (OFA) problem, which can be geometrically analyzed in a rectangular coordinate system and is NP-hard. First, we study the OFA problem in the case of uniformly distributed sensors with identical charging demands, we develop the uniform charging strategy (UCS) to bound the total charging expenditure as Θ(1) for any number of sensors N. Based on the acquired insights, we further studied the OFA problem when the distribution of charging demands is Gaussian. We bound the total charging expenditure as Θ(1) for any number of sensors N, by developing the layered charging strategy (LCS). Extensive simulation results confirmed the performance of our design compared with two baseline algorithms. Both of the theoretical and simulations results reveal that the total energy expenditure of the charger is strongly related to the sensors' charging demands, however, is less affected by the number of sensors in the network.

BIM-VE-Based Optimization of Green Building Envelope from the Perspective of both Energy Saving and Life Cycle Cost

In the context of the increasingly severe energy crisis and global warming, green buildings and their energy-saving issues are being paid more attention in the world. Since envelope optimization can significantly reduce the energy consumption of green buildings, value engineering (VE) technology and building information modeling (BIM) technology are used to optimize the envelope of green buildings, which takes into account both energy saving and life cycle cost. The theoretical framework of optimization for green building envelope based on BIM-VE is proposed, including a BIM model for architecture, a life cycle cost analysis model, energy-saving analysis model, and a value analysis model. In the life-cycle cost model, a mathematical formula for the life-cycle cost is established, and BIM technology is used to generate a bill of quantity. In the energy-saving analysis model, a mathematical formula for energy saving is established, and BIM technology is used for the building energy simulation. In the scheme decision-making sub-model, VE technology integrating life cycle cost with energy saving is used to assess the envelope schemes and select the optimal one. A prefabricated project case is used to simulate and test the established methodology. The important results show that the 16 envelope schemes make the 16 corresponding designed buildings meet the green building evaluation standards, and the optimal envelope scheme is the “energy-saving and anti-theft door + exterior window 2+ floor 1+ exterior wall 1 + inner shear wall + inner partition wall 2 + planted roof” with the value 10.80 × 10−2 MW·h/ten thousand yuan. A significant finding is that the value generally rises with the increase of energy-saving rate while the life cycle cost is irregular with the increase of energy-saving rate. Compared with previous efforts in the literature, this study introduces VE technology into architectural design to further expand the current boundary of building energy-saving theory. The findings and suggestions will provide a valuable reference and guidance for the architectural design industry to optimize the envelope of green buildings from the perspective of both energy saving and life cycle cost.

Joint Analysis of Cost and Energy Savings for Preliminary Design Alternative Assessment

The building sector plays a central role in addressing the problem of global energy consumption. Therefore, effective design measures need to be taken to ensure efficient usage and management of new structures. The challenging task for designers is to reduce energy demands while maintaining a high-quality indoor environment and low costs of construction and operations. This study proposes a methodological framework that enables decision-makers to resolve conflicts between energy demand and life cycle costs. A case study is analyzed to validate the proposed method, adopting different solutions for walls, roofs, floors, windows, window-to-wall ratios and geographical locations. Models are created on the basis of all the possible combinations between these elements, enriched by their thermal properties and construction/management costs. After the alternative models are defined, energy analyses are carried out for an estimation of consumption. By calculating the total cost of each model as the sum of construction, energy and maintenance costs, a joint analysis is carried out for variable life cycles. The obtained results from the proposed method confirm the importance of a preliminary assessment from both energy and cost points of view, and demonstrate the impact of considering different building life cycles on the choice of design alternatives.

Numerical analysis of energy savings due to the use of PCM integrated in lightweight building walls

A new type of PCM layer integrated into an exterior building wall is to reduce the amplitude of the indoor temperature and maintaining the better thermal comfort for human beings. A numerical simulation has been carried out with and without integration of PCM in building walls. In this paper, the effect of different configuration of external building walls were studied and analyzed by the integration of PCM building walls. Using finite difference method, one dimensional transient heat transfer model was developed and solved. The indoor temperature was also analyzed for the summer and winter climatic conditions of Chennai city, India (13.1 Latitude and 79.9 Longitude) in the PCM and Non-PCM buildings. The building wall consists of clay brick with filled with PCM. The numerical simulation result shows that, PCM filled with clay brick wall improves the thermal inertia significantly. Location of PCM layer in the building wall is one of the important factors to reduce the heat gain in the building wall before it enters the room.

Retrofitting High-Rise Residential Building in Cold and Severe Cold Zones of China—A Deterministic Decision-Making Mechanism

This study aimed to develop a deterministic decision-making mechanism for finding the optimum set of retrofit solutions of existing high-rise residential buildings in two different climatic zones of China. The retrofit solutions were critically examined with different energy saving targets based on the local climatic conditions, building features, and retrofit costs in cold and severe cold zones comparatively. By making the extensive review and analyzing considerable statistics data and cost information, net present value (NPV) method was employed in the prototype building apartments to develop this deterministic model. The results demonstrated that the heating system is the most important factor in saving energy and obtaining the optimum revenue in these two regions. The highest optimal NPV can be obtained by achieving 60% energy saving in the cold zone, as energy saving is around 319 kWh/m2/year with the total retrofit costs of USD $3560, while it is 281 kWh/m2/year with the total retrofit costs of USD $3480 to achieve the 50% energy-saving target in the severe cold zone. Based on the analysis of energy savings and retrofit costs, the results can be effectively implemented for the purpose of creating sustainable retrofits in existing buildings, and the model can be adapted for selecting appropriate retrofit choices in other climatic zones.

Analysis of Energy Savings in Packing Paper Mill with EGAER Tool

Analysis of Energy Savings in Packing Paper Mill with EGAER Tool

Integrated Analysis of Energy Saving and Thermal Comfort of Retrofits in Social Housing under Climate Change Influence in Uruguay

Energy improvement studies normally use energy demand reduction as an indicator, disregarding dwellings that do not use air-conditioning systems or do so only under extreme weather conditions. They also do not quantify the impact of climate change on results. This research seeks to evaluate and prioritize energy improvements for existing Uruguayan dwellings, assessing energy demand and thermal comfort in both the current and future climate. A social dwelling was monitored and calibrated to assess energy efficiency measures simulating the current climate and for 2050 (IPCC Scenario A2). The results show that improvements must be linked to the use of air-conditioning in dwellings. When air-conditioning use is unknown, for example, in public policy, thermal transmittance in walls should be between 0.50–0.61 W/m2 K, in roofs between 0.32–0.47 W/m2 K, in openings 2.7 W/m2 K, airtightness under 5 ACH n50 and with solar protections. However, when the use under free running is certain, thermal transmittance in walls and roofs should be 0.85 W/m2 K with an airtightness of 9.2 ACH n50 and solar protection used to avoid overheating. The operational ventilation and solar protection parameters were helpful to guarantee comfort, underlining the need for their inclusion and to train those who use them.

Energy-saving analysis of air source heat pump integrated with a water storage tank for heating applications

Due to declining fossil fuel reserves and environmental contamination, the use of air source heat pumps has become a significant alternative to fossil fuel heating. In this paper, a heating system using an air source heat pump integrated with a water storage tank was constructed, to improve the operating efficiency of the air source heat pump (ASHP) at low ambient temperatures. It ran under a novel operation strategy of ASHP heating and water storage tank charging during the daytime, ASHP switching off and the water storage tank discharging at night. Under this approach, the ASHPs always operated at higher ambient temperatures and switched off at lower ambient temperatures. The test system of the air source heat pump integrated with a water storage tank was installed and monitored long-term in a practical building in Beijing. According to the monitored data from December 1st, 2018 to March 11th, 2019, the daily average ambient temperature varied from −9.3 °C to 11.3 °C, while the daily average indoor temperature ranged from 21.0 °C to 23.0 °C. The ASHP's daily average coefficient of performance (COP) on the coldest day was 2.35, and the seasonal coefficient of performance (SCOP) was 2.95. As compared to the continuous operation mode, the ASHP's daily average COP was enhanced by 14.0% on the coldest day, and the SCOP has improved by 26.1%. The air source heat pump integrated with a water storage tank has significant energy-saving potential under this operation strategy.

Intelligent Building Equipment Control Technology and Energy Saving Analysis

In the process of rapid urbanization in China, the proportion of buildings’ energy consumption is increasing, and the contradiction between energy and development is becoming increasingly prominent. On the basis of realizing its intelligent and comfortable goals, intelligent buildings have attracted wide attention from society due to their large operational performance. The research on energy saving of intelligent buildings has become an important direction for energy conservation research. The energy consumption of intelligent building equipment operation accounts for about 60% of energy consumption, which has become the main energy consumption object of intelligent buildings. This paper takes building equipment operation control as the research object, and introduces the energy saving ideas of building intelligent systems from the perspective of energy saving control, including energy saving control of building equipment, energy saving control of cold and heat sources, energy saving control of lighting, etc., and points out the future development direction of energy saving in intelligent buildings.

Study on Energy Planning and Energy Saving Analysis of Cooling and Heating Load of a Building Complex

With the rapid development of the construction industry, the demand for energy is also expanding rapidly. The cooling and heating load in the building consumes a lot of energy, which is an important part of the building energy consumption. This paper takes the actual project as an example, under the guidance of the relevant national laws and regulations, analyzes the energy endowment provided by the surrounding environment of the project, and predicts and analyzes the demand of cooling and heating load of the project, so as to further put forward the energy planning scheme of cooling and heating load of the project and analyze its energy saving effect.

Analysis of electricity energy savings with Grid-Tie system connected to utility grid

The microgrid consists of at least one energy source that is connected to a load in a relatively small area. In practice, microgrid are divided into two types, off-grid systems or often said to be standalone systems and on-grid systems that are connected to utility networks. The use of renewable energy sources, such as photovoltaic, has become an alternative energy for the problem of electricity energy deficits. This research examines the possibility of saving power consumption from the network using a grid-tie inverter (GTI) power converter in a microgrid configuration so synchronization can be made between renewable energy systems and utility networks. The integration of photovoltaic energy resources with the grid system will increase the value of electricity capacity while reducing the use of fossil fuels, as well as a positive impact where the use of renewable energy can reduce energy use and bills to be paid. Integration of grid tie testing carried out without a load can convert the power generated by almost 90% distributed in the utility network, while testing with a load using a grid tie system, can save power up to 70% of the energy supplied by the utility network.

Energy Saving Analysis of No-load Loss of Electric Welding Equipment

In this paper, two types of electric welding equipment are studied. First of all, YD / k-505fl4 and bx3-500 type welding machines do not have the function of self power off in standby state. It is necessary to install an intelligent welding machine power saving system to control the power off of the primary side of the transformer under the no-load state of the welding machine, and then cut off the no-load loss of the welding machine. Secondly, yd-500-kr II series welding machine has the function of standby, delay and self power off. Due to the unreasonable setting of welding parameters, the uneconomical selection of welding cable and the unreasonable layout of welding machine, the overall energy loss of welding machine is large. Finally, weathering steel is used in the welding process design, and the performance, energy consumption and economic practicability of the material are analyzed.

Analysis of permanent magnet servo motor performance with different semi-ferromagnetic sleeve materials

Proposed is a study on the application of a semi-ferromagnetic sleeve in a permanent magnet servo motor (PMSM). First, taking the no-load electromotive force as the research object, the optimal sleeve permeability of the PMSM was determined using the finite element method, and the correctness was verified using an analytical algorithm. In the analytical calculation process, to solve the calculation problem of the no-load leakage flux coefficient caused by the complex distribution of the pole-to-pole leakage flux, an iterative calculation method is proposed. Second, based on the optimization sleeve permeability, the variation of the eddy current loss with different sleeve conductivity was analyzed, and the optimal conductivity value was determined. Finally, variations in current and power factor before and after optimization were compared and analyzed, and the effect of the sleeve electromagnetic characteristics on the motor performance was analyzed. Motor performance after optimization could be consistent with that of before optimization by reducing the thickness of the permanent magnet, which provides a theoretical basis for the optimization analysis of energy and material savings of the PMSM.

Energy-saving Analysis of Energy Consumption in Public Buildingsand Case Application

This paper introduces the basic principles and characteristics of the energy consumption monitoring system, design situation, equipment parameters, system form and application examples of energy consumption monitoring system in public buildings, explains the role of public building energy monitoring system. Starting from the artificial collection and data transmission, this paper analyzes the application status of public building energy consumption monitoring technologies, and based on this, proposes application countermeasures based on energy conservation management under public building energy consumption monitoring system, which can provide some references for energy-saving application technology in public buildings.

Thermal Performance and Energy Saving Analysis of Indoor Air–Water Heat Exchanger Based on Micro Heat Pipe Array for Data Center

According to the temperature regulations and high energy consumption of air conditioning (AC) system in data centers (DCs), natural cold energy becomes the focus of energy saving in data center in winter and transition season. A new type of air–water heat exchanger (AWHE) for the indoor side of DCs was designed to use natural cold energy in order to reduce the power consumption of AC. The AWHE applied micro-heat pipe arrays (MHPAs) with serrated fins on its surface to enhance heat transfer. The performance of MHPA-AWHE for different inlet water temperatures, water and air flow rates was investigated, respectively. The results showed that the maximum efficiency of the heat exchanger was 81.4% by using the effectiveness number of transfer units (ε-NTU) method. When the max air flow rate was 3000 m3/h and the water inlet temperature was 5 °C, the maximum heat transfer rate was 9.29 kW. The maximum pressure drop of the air side and water side were 339.8 Pa and 8.86 kPa, respectively. The comprehensive evaluation index j/f1/2 of the MHPA-AWHE increased by 10.8% compared to the plate–fin heat exchanger with louvered fins. The energy saving characteristics of an example DCs in Beijing was analyzed, and when the air flow rate was 2500 m3/h and the number of MHPA-AWHE modules was five, the minimum payback period of the MHPA-AWHE system was 2.3 years, which was the shortest and the most economical recorded. The maximum comprehensive energy efficiency ratio (EER) of the system after the transformation was 21.8, the electric power reduced by 28.3% compared to the system before the transformation, and the control strategy was carried out. The comprehensive performance provides a reference for MHPA-AWHE application in data centers.

Energy Saving Analysis and Simulation for Home Electricity

This paper presents the energy saving method by applying the voltage control technique on a single-phase AC source to a thyristor rectifier and an IGBT inverter with LC filter. Based on the LC filter parameter, the values of the gain for the controller are obtainable. The proposed controller structure consists of two loops arranged in a cascaded model. The output of the first loop is the capacitor current. This current is added to the load current in order to obtain the current reference. This reference current value will be compared with the inverter current which produces the error signal to be fed into the second loop in the cascade system. The output of the second loop is the inverter voltage. This voltage is added to the load voltage to produce the voltage reference. This reference is fed to the pulse width modulation generator via the controller and compared with the triangular wave. This energy-saving circuit is designed in blocks using MATLAB Simulink.

Energy savings potential from prismatic glass structure

The simulation analysis of the potential energy savings from the prismatic glass structure has been provided. The two conventional triple glazings and two proposed triple glazings with prismatic glass have been experimentally tested to obtain the realistic angular selective optical properties. The experimental results have been compared with conventional triple glazing with clear glass panes and triple glazing with solar control pane applied. The comparison indicated high potential advantages of triple glazing with prismatic glass structures (especially for reverse symmetrical prism): low transmittance for high solar altitude–summer condition, high transmittance for low solar altitude–winter condition. The obtained transmittance characteristics were used as input data for the annual simulation of a typical office in the Czech Republic. The simulation has been performed in TRNSYS and TRNBuild software. The gathered results confirmed, that prismatic glass structure can bring energy savings for both cooling and heating energy demands.