제조업 분야 에너지절약시설 투자에 대한 에너지 절감효과 분석

김형건(Hyung-Gun Kim),홍인기(Inkee Hong),백인걸(Ingul Baek) 한국자료분석학회 2021 Journal of the Korean Data Analysis Society Vol.23 No.2

본 연구는 2013~2016년 한국신용평가원의 기업자료와 한국에너지관리공단의 에너지 사용량 자료를 사용하여 제조업에서 에너지절약시설에 대한 투자가 에너지 절감량에 미치는 영향을 분위수 회귀모형을 통해 추정하였다. 에너지절약시설에 대한 투자가 에너지 절감에 긍정적으로 작용하리라는 예상에는 큰 이견이 없을 것이나, 이미 일정 수준의 에너지 절감을 달성한 기업의 경우에는 추가적인 시설 투자를 하더라도 에너지 절약 효과가 체감할 수 있다는 점은 아직 국내에서 실증적으로 확인된 바가 없다. 그러므로 본 연구는 절약시설 투자의 수확체감효과를 실증적으로 분석하여 관련 주제를 분야의 학문적 빈틈을 메우자고 한다. 경제학적 결론에 도달하기 위해 조건부 평균을 추정하는 전통적인 회귀모형에서 벗어나, 분위수 회귀모형을 사용하여 에너지 절감량 분위수에 따른 에너지절약시설 투자효과를 차별적으로 추정한다. 추정 결과, 우리나라 제조업 기업들의 에너지 절감량은 기업의 특성이 유사하다면 절감량이 높은 기업군일수록 에너지 절약시설 투자에 대한 영향이 적었으나, 에너지 절감량이 낮은 기업군일수록 투자의 영향이 큰 것으로 나타났다. 따라서 에너지 절감량에 따라 기업에게 차등적인 지원기준을 제시하여 에너지 절약의 노력이 계속될 수 있도록 정책적 에너지절감량 달성목표를 기업별로 설정하는 것이 요구된다. We apply a quantile regression model to shed light on the effect of energy-saving facilities investment on the amount of energy savings in the Korean manufacturing industry based on the 2013~2016 Corporation dataset from KisValue of NICE Investors Service and Energy Consumption Survey Data from Korea Energy Agency. There is little doubt on the role of the investment in efficiently reducing the amount of energy consumption without loss in production. However, to the best of our knowledge, there is no literature of empirical studies about diminishing return on the marginal investment for energy saving in the manufacturing industry. The present study fills the gap by documenting the law of diminishing returns in the field of manufacturing for the investment in energy saving facilities. To achieve the economic purpose, we the effect of the investment by differentiating the group in terms of a quantile of energy savings, instead of resorting to linear models. We find that firms with high energy saving have lower marginal returns of the investment on the facilities, whereas firms with low energy saving tend to show higher marginal returns on those investments. Therefore, it is required to provide a reasonable political system to save energy for the firms in the manufacturing industry by differentiating the level of goals considering the level of energy savings and other variables.

Investigation of Remanufacturing Methods Utilizing Mechanically-Generated and Gas-Atomized Feedstock Production for Directed Energy Deposition Processing Through Specific Energy Consumption Modeling

Marcus A. Jackson,Dan J. Thoma,Frank E. Pfefferkorn 한국정밀공학회 2023 International Journal of Precision Engineering and Vol.10 No.3

The objective of this work was to assess the energy consumption of a novel remanufacturing method that utilizes mechanically-generated feedstock for directed energy deposition. Gas-atomization is the state-of-the-art production process for directed energy deposition feedstock, and for this work was incorporated into a remanufacturing process path to provide a comparison method. Specific energy consumption models of remanufacturing utilizing both of these proposed process paths were developed and applied to a case study to investigate energy saving opportunities for future manufacturing paradigms. The energy modelling was done in three stages. First, the mechanically-generated feedstock production energy consumption model was generated from experimental observation. Second, the gas-atomized feedstock production energy consumption model was generated from a combination of experimental observation, reported estimates from the manufacturer, and data found in the literature. Lastly, the energy consumption model of directed energy deposition was derived from experimental observation and compares favorably with reported estimates in the literature. With the models, the specific energy consumption in the two process paths were compared and their application was demonstrated by estimating the energy consumption to remanufacture a bracket. The two feedstock production methods had similar specific energy consumptions. The specific energy consumption of the directed energy deposition process was the greatest component in the respective remanufacturing paths by an order of magnitude; increasing deposition rate is the most important factor for lowering the overall specific energy consumption. The analyzed remanufacturing technologies were estimated to consume less energy than replacement when repairing up to approximately 15% of the original part’s mass.

Identification of High Significance Product Items Through the Analysis of Energy Consumption in Steel Factory

A.B.M. Salman Rahman,이명배,Vasanth Ragu,임종현,조용윤,박장우,신창선 한국지식정보기술학회 2019 한국지식정보기술학회 논문지 Vol.14 No.3

Analysis and modeling of industrial energy are currently a time-insertion process because more and more energy is consumed for economic growth in an industrial factory. Industrial energy consumption analysis and prediction play a very important role in improving the energy utilization rate to make profitable things for industrial companies or factories. Industrial factory owners are also starting to realize the importance of energy analysis and predictions to make a plan for better energy utilization for their factories. So, this is the high time to work as a technological supportive hand with an industrial factory in order to improve their energy utilization for making some profitable things for industrial organizations and also for our society. It is not so easy process to analyses energy and realizes accurate predictions of industrial energy consumption. Therefore, this study deals with analysing total usages of 24-hours energy consumption for every month and also total usages of energy for the year 2017. We find out the difference between total usages of energy and demands of energy for the year 2017. We make relation curve between per-day usages of energy and different types of materials weight for different types of manufacturing product, and also make a relation curve between per-day usages of energy, demands of energy and total materials weight for manufacturing products for the year 2017. We use the correlation method to find out the relationship of usages of energy with different types of materials weight for manufacturing products. Finally, we find out the total usages of energy for manufacturing every product and make a decision about the energy utilization.

Energy Consumption Evaluation in Stamping Workshops via a Discrete Event Simulation-Based Approach

Wei Xiong,Haihong Huang,Lei Li,Lei Gan,Libin Zhu,Zhifeng Liu 한국정밀공학회 2022 International Journal of Precision Engineering and Vol.9 No.6

Stamping is employed in a wide range of applications in industry, which is composed of discrete flow energy-intensive processes. Durations of stamping activities are much shorter than that of mold changing and transportation, which makes energy consumption in stamping workshops greatly affected by the production scheme and the proportion of transportation volume. Different from machining that has been widely discussed, there is less research on energy saving in stamping workshops. This paper aims to evaluate the energy consumption of stamping on the workshop level. A theoretical model and a discrete event simulation model were developed based on energy flow and material flow in the workshop. The theoretical model was used to calculate each component of energy consumption based on production-related data. The simulation model was used to predict the overall energy required in the workshop when subjected to changes in its production conditions. Impacts of influence factors, including machine failure rate, proportion of transportation volume, and production scheme on energy consumption, makespan, and machine utilization rates, were studied to find opportunities for energy reduction and production efficiency improvement. Finally, a case study of a stamping workshop for forklifts validated the proposed approach, and optimization measures were suggested, implemented, and verified. Results have found that under the same production scheme (suppose each press has the same failure rate), the balance between energy use and makespan was achieved when the proportion of transportation volume was 1/2. This simulation-based approach provides a useful tool for evaluating and reducing energy consumption and helps operators to perform energy-saving actions in stamping workshops.

Simulation-Based Energy Usage Profiling of Machine Tool at the Component Level

이원균,이찬영,민병권 한국정밀공학회 2014 International Journal of Precision Engineering and Vol.1 No.3

This paper describes a virtual machine tool (VMT) that can be used to estimate the energy consumption of machine tools at the component level. The VMT was designed by focusing on accurately estimating the dynamic behavior and energy consumption of the servo system, which has a major impact on the total energy consumption. Simulation models of the controller and feed drive were constructed. The energy consumption levels of the feed drive components were analyzed theoretically and integrated into the model. An experimental setup of the servo system incorporating a hardware-in-the-loop simulation testbed was constructed to evaluate the proposed model. Simplified models of the spindle, auxiliary units, and cutting dynamics were included in the VMT to estimate the energy consumption of the machine tool components during milling. This simulation technique was used to quantify the effects of machine tool design modification and process control and to simulate the relationship between the specific energy consumption and the material removal rate in order to reduce the overall energy consumption.

A Comparison of Energy Consumption in Bulk Forming, Subtractive, and Additive Processes: Review and Case Study

윤해성,이장엽,김형수,김민수,김은섭,신용준,추원식,안성훈 한국정밀공학회 2014 International Journal of Precision Engineering and Vol.1 No.3

In addition to the steps taken to ensure optimal efficiency in industry, significant effort has been directed towards the green and sustainable manufacturing practices. In this paper, we review conventional and state-of-the-art manufacturing technologies to provide insight into energy consumption at the processing level. In the review, collected energy data were summarized for three manufacturing categories: conventional bulk-forming, subtractive, and additive manufacturing (AM) processes. Additive processes, in particular, are strongly emphasized in the Advanced Manufacturing Initiatives proposed recently by the United States government. Currently, the specific energy consumption (SEC) of additive processes is estimated to be ~100-fold higher than that of conventional bulk-forming processes, with subtractive processes showing intermediate values that varied over a wide range in terms of scale. Although SEC may vary with respect to the details, in general, the research showed a negative correlation with respect to the reciprocal logarithmic form of the productivity. In addition to the literature review presented, we performed case studies for the three manufacturing processes, to provide practical examples of energy consumption. Additionally, our results indicated that AM processes may require more extensive evaluation; i.e., an assessment of the entire manufacturing cycle, for more accurate prediction of the subsequent environmental impact.

일유체 노즐을 이용한 실내 수분무 가습 방식 클린룸의 에너지 절감에 관한 실험적 연구

박수빈(Su-Bin Park),송원일(Won-Il Song),유경훈(Kyung-Hoon Yoo),태경응(Kyung-Eung Tae),김용식(Yong-Sik Kim),양지석(Ji-Seok Yang),송덕용(Deog-Yong Song),권오명(Oh-Myoung Kwon),황정호(Jungho Hwang) 대한설비공학회 2018 대한설비공학회 학술발표대회논문집 Vol.2018 No.6

An Approach for Reducing Cutting Energy Consumption with Ultra-High Speed Machining of Super Alloy Inconel 718

Bing Wang,Zhan-qiang Liu,Qinghua Song,Yi Wang,iaoping Ren 한국정밀공학회 2020 International Journal of Precision Engineering and Vol.7 No.1

High energy efficient machining is beneficial for sustainable manufacture which is an important target pursued by workshops. The paper aims to prove the feasibility for reducing cutting energy consumption with ultra-high speed machining (UHSM) of super alloy Inconel 718. Firstly, orthogonal cutting experiments of Inconel 718 are performed with a wide cutting speed range. Through analyses of chip micrographs, it is found that plastic deformation accompanied with ductile fracture contributes to serrated chip formation, while fragmented chips are produced through brittle fracture. The results demonstrate that brittle regime machining can be realized for Inconel 718 with ultra-high cutting speeds. Secondly, considering varied deformation behavior for chips with different morphologies, specific cutting energy models for HSM under varied cutting parameters are developed and verified. Then the influences of cutting speed and uncut chip thickness on cutting energy consumption during HSM are revealed. The research results demonstrate the practicability for reducing cutting energy consumption with brittle regime machining of Inconel 718. At last, the relationship between AE signals and cutting energy consumption is explored, and it proves that AE signals are applicable in monitoring cutting energy consumption. The research can provide guidance for energy saving through optimizing cutting parameters.

복수고객 군을 갖는 주문생산 제조시스템에서 에너지소비효율 최적화와 생산순서, 생산속도 및 주문수용 통제의 통합 구현에 관한 연구

김은갑 한국생산관리학회 2019 한국생산관리학회지 Vol.30 No.4

We study a joint production sequencing, production rate, and order admission controls for maximizing energy consumption efficiency in a multi-class make-to-order manufacturing firm. Recently, production rate control has received attention in research because of its effectiveness in reducing demand variability and incorporating the energy consumption problem into production planning for sustainable manufacturing. We presented a Markov decision process model to investigate the effect of production sequencing, production rate, and order admission controls on the firm’s profit and implemented numerical investigation using the value iteration algorithm. The numerical results indicate that production sequencing is only affected by backorder cost and is unaffected by unit sales revenue or order rejection cost. They also show that systems with variable production rates achieve a higher profit than those with a fixed rate. In particular, it is observed that the variable production rate option is more effective as the energy consumption cost becomes larger. We also observe that the higher the revenue parameter and ratio of backorder costs between two customer classes are, the more valuable the variable production rate option is. 본 논문은 복수고객 군을 갖는 주문생산 제조기업을 대상으로 에너지소비효율 최적화와 생산순서, 생산속도 및 주문수용 통제를 통합적으로 수립하는 문제를 제안하고 있다. 수요 변동성을 완화시키는데 효과적이고, 지속가능한 제조 관점에서 에너지 소비 이슈를 생산계획수립에 반영할 필요성이 커졌기 때문에, 최근에 제조시스템의 생산속도 통제를 다루는 연구들이 주목을 받고 있다. 본 논문은 주문수용통제, 생산속도통제, 생산순서통제가 기업수익에 미치는 영향을 분석하기 위하여 마코프 의사결정모형을 제시하였고, 가치반복알고리즘을 사용하여 수치 분석을 수행하였다. 수치실험 결과, 주문처리순서는 계층별 판매단가와 주문거절비용의 크기에는 영향을 받지 않고, 계층별 지연재고비용의 크기에 의해서만 결정된다는 사실을 알 수 있었다. 이는 고객수용 통제와 서비스속도 통제가 이루어지지 않는 복수고객 군 시스템의 최적 서비스 순서 통제 전략인 규칙(지연주문비용과 서비스 속도의 곱의 크기 순서대로 고객 군들에 대한 서비스를 진행)이 본 연구 모형의 생산순서 통제에서도 최적 전략이 될 수 있음을 시사하는 결과이다. 본 논문은 다양한 수치 예제들에 대한 실험을 통해 생산속도가 평균값으로 고정된 시스템보다는 탄력적으로 통제되는 시스템에서 더 높은 기대수익을 올릴 수 있음을 알 수 있었다. 수치실험 결과에 따르면 생산속도 통제옵션은 에너지소비비용이 낮을 때보다 높을 때, 판매단가가 높을 때보다 낮을 때, 그리고 두 고객계층 간 지연재고비용 비율이 낮을 때보다 높을 때 더 효과적이었다. 주문거절비용이 판매단가 이하일 경우에는 주문수용 통제옵션에 의한 수익성 개선 효과가 뚜렷하지만, 반대일 경우에는 제한적이었다. 기대수익에 대한 주문수용 통제옵션의 영향은 두 고객 군의 제품판매단가 비율에 의해 크게 달라질 수 있음도 알 수 있었다. 한편, 수치실험 결과는 생산속도 통제를 구현하기 위해 많은 생산속도 선택 옵션을 가져갈 필요가 없으며, 세 가지의 생산속도 선택 옵션만으로도 고정생산속도를 사용할 때보다 높은 수익성 개선 효과를 도모할 수 있음을 보여 주었다.

Application of Heuristic Approaches to Minimization of Energy Consumption in Inner Layer Scrubbing Process in PCB Manufacturing

박유진,이규봉 한국정밀공학회 2012 International Journal of Precision Engineering and Vol. No.

This research considers the problem of minimizing the total amount of energy consumption in inner layer scrubbing process in printed circuit board (PCB) manufacturing. The degree of adhesion between interlayers in multilayer circuit board (MCB) manufacturing is the most critical factor in reliability of products. Generally, the inner layer scrubbing process is the process that removes certain debris such as oxide or fingerprints occurring on surface of tin core (inner materials or inner circuit board). Also, this process makes the surface of copper rough in order to stick liquid photo resist (LPR) and dry film well by enhancing the adhesion. In order to promote the adhesion, the formal way is to use brushes or oxide chemical by making the surface of copper rough. Through these ways, we can minimize the heat shock and defective adhesion. So, in this research, heuristic approaches are applied to inner layer scrubbing process in order to find the optimal operating conditions of the process which minimize the total amount of energy consumption while keeping the required quality, that is,roughness in a certain prespecified range. The model for describing the roughness behavior in inner layer scrubbing process is constructed by using categorical regression analysis. And then, the performance of the heuristic method is investigated and compared to that of a random search approach. Numerical results reveal that the genetic algorithm provides moderately good performance with respect to the measure of minimizing the total amount of energy consumption in inner layer scrubbing process as well as the computation time.