Effectiveness of the GM(1,1) model on linear growth sequence and its application in global primary energy consumption prediction

Kybernetes ◽  
2016 ◽  
Vol 45 (9) ◽  
pp. 1472-1485 ◽  
Author(s):  
Chaoqing Yuan ◽  
Ding Chen

Purpose The purpose of this paper is to investigate the effectiveness of GM(1,1) model on linear growth sequences (LGS) by random experiments and global primary energy consumption is predicted as by the GM(1,1) and the autoregressive integrated moving average (ARIMA) model, which is used as a reference. Design/methodology/approach LGS generated randomly are used for GM(1,1) modeling. The results of the massive repeated random experiments are analyzed to test the effectiveness of the GM(1,1) model and global primary energy consumption is predicted using the GM(1,1) model and the ARIMA model. Findings The use of the GM(1,1) model is effective when used for a LGS and the model is proven to be reliable by the experiments. Global primary energy consumption is predicted with the GM(1,1) model and the ARIMA model as a case study, and the results show that GM(1,1) is quite good. Global primary energy consumption will increase by 1.03 percent in 2016. Originality/value The contribution of this paper includes the following: first, the applicability of the GM (1,1) model is further discussed with random experiments and it is feasible for a LGS; second, random experiments provide good proof that four data are enough for GM(1,1) modeling, and GM(1,1) model is reliable; third, prediction by using GM(1,1) model with small data is even better than time-series analysis in the case study.

Mathematics ◽  
2020 ◽  
Vol 8 (10) ◽  
pp. 1722
Author(s):  
Yu-Sheng Kao ◽  
Kazumitsu Nawata ◽  
Chi-Yo Huang

Forecasting energy consumption is not easy because of the nonlinear nature of the time series for energy consumptions, which cannot be accurately predicted by traditional forecasting methods. Therefore, a novel hybrid forecasting framework based on the ensemble empirical mode decomposition (EEMD) approach and a combination of individual forecasting models is proposed. The hybrid models include the autoregressive integrated moving average (ARIMA), the support vector regression (SVR), and the genetic algorithm (GA). The integrated framework, the so-called EEMD-ARIMA-GA-SVR, will be used to predict the primary energy consumption of an economy. An empirical study case based on the Taiwanese consumption of energy will be used to verify the feasibility of the proposed forecast framework. According to the empirical study results, the proposed hybrid framework is feasible. Compared with prediction results derived from other forecasting mechanisms, the proposed framework demonstrates better precisions, but such a hybrid system can also be seen as a basis for energy management and policy definition.


Energies ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1973
Author(s):  
Piotr Michalak ◽  
Krzysztof Szczotka ◽  
Jakub Szymiczek

Thermal refurbishment of buildings results in certain energy, financial, and environmental effects. Such investments are financially supported in Poland after meeting the legally defined conditions of thermal protection and energy consumption. This paper presents a complex thermal modernization of a school building, performed by following Polish regulations. A detailed description of the studied object was given, and the calculation procedure was described. Then an optimal variant of an investment and an ex-post analysis were described. Simple payback time (SPBT) of modernization measures was from 15.8 years (insulation of the ceiling under the unheated attic) to 87 years for insulation of the wooden external wall, with 35.6 years for the whole project, which is shorter than the predicted lifespan of the whole building (50–70 years). Annual calculated heating demand decreased from 464.78 to 168.73 GJ, resulting in the primary energy consumption indicator (EP) of 484.44 and 129.46 kWh/m2, respectively. Thermal refurbishment with the replacement of an old boiler into a new wood-pellet one resulted in a significant reduction of SO2 and dust emissions from 451 to 27.5 kg and from 399 to 13 kg, respectively.


2017 ◽  
Author(s):  
Abdul Rahman ◽  
Ansari Saleh Ahmar

This research has a purpose to compare ARIMA Model and Holt-Winters Model based on MAE, RSS, MSE, and RMS criteria in predicting Primary Energy Consumption Total data in the US. The data from this research ranges from January 1973 to December 2016. This data will be processed by using R Software. Based on the results of data analysis that has been done, it is found that the model of Holt-Winters Additive type (MSE: 258350.1) is the most appropriate model in predicting Primary Energy Consumption Total data in the US. This model is more appropriate when compared with Holt-Winters Multiplicative type (MSE: 262260,4) and ARIMA Seasonal model (MSE: 723502,2).Paper ini dipresentasikan pada The 3th International Conference on Green Design and Manufacture 2017 (Krabi, Thailand, 29-30 April 2017), diunggah oleh Ansari Saleh Ahmar


2012 ◽  
Vol 9 (2) ◽  
pp. 65
Author(s):  
Alhassan Salami Tijani ◽  
Nazri Mohammed ◽  
Werner Witt

Industrial heat pumps are heat-recovery systems that allow the temperature ofwaste-heat stream to be increased to a higher, more efficient temperature. Consequently, heat pumps can improve energy efficiency in industrial processes as well as energy savings when conventional passive-heat recovery is not possible. In this paper, possible ways of saving energy in the chemical industry are considered, the objective is to reduce the primary energy (such as coal) consumption of power plant. Particularly the thermodynamic analyses ofintegrating backpressure turbine ofa power plant with distillation units have been considered. Some practical examples such as conventional distillation unit and heat pump are used as a means of reducing primary energy consumption with tangible indications of energy savings. The heat pump distillation is operated via electrical power from the power plant. The exergy efficiency ofthe primary fuel is calculated for different operating range ofthe heat pump distillation. This is then compared with a conventional distillation unit that depends on saturated steam from a power plant as the source of energy. The results obtained show that heat pump distillation is an economic way to save energy if the temperaturedifference between the overhead and the bottom is small. Based on the result, the energy saved by the application of a heat pump distillation is improved compared to conventional distillation unit.


Energies ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2538
Author(s):  
Praveen K. Cheekatamarla

Electrical and thermal loads of residential buildings present a unique opportunity for onsite power generation, and concomitant thermal energy generation, storage, and utilization, to decrease primary energy consumption and carbon dioxide intensity. This approach also improves resiliency and ability to address peak load burden effectively. Demand response programs and grid-interactive buildings are also essential to meet the energy needs of the 21st century while addressing climate impact. Given the significance of the scale of building energy consumption, this study investigates how cogeneration systems influence the primary energy consumption and carbon footprint in residential buildings. The impact of onsite power generation capacity, its electrical and thermal efficiency, and its cost, on total primary energy consumption, equivalent carbon dioxide emissions, operating expenditure, and, most importantly, thermal and electrical energy balance, is presented. The conditions at which a cogeneration approach loses its advantage as an energy efficient residential resource are identified as a function of electrical grid’s carbon footprint and primary energy efficiency. Compared to a heat pump heating system with a coefficient of performance (COP) of three, a 0.5 kW cogeneration system with 40% electrical efficiency is shown to lose its environmental benefit if the electrical grid’s carbon dioxide intensity falls below 0.4 kg CO2 per kWh electricity.


2018 ◽  
Vol 882 ◽  
pp. 215-220
Author(s):  
Matthias Koppmann ◽  
Raphael Lechner ◽  
Tom Goßner ◽  
Markus Brautsch

Process cooling and air conditioning are becoming increasingly important in the industry. Refrigeration is still mostly accomplished with compression chillers, although alternative technologies are available on the market that can be more efficient for specific applications. Within the scope of the project “EffiCool” a technology toolbox is currently being developed, which is intended to assist industrials users in selecting energy efficient and eco-friendly cooling solutions. In order to assess different refrigeration options a consistent methodology was developed. The refrigeration technologies are assessed regarding their efficiency, CO2-emissions and primary energy consumption. For CCHP systems an exergetic allocation method was implemented. Two scenarios with A) a compression chiller and B) an absorption chiller coupled to a natural gas CHP system were calculated exemplarily, showing a greater overall efficiency for the CCHP system, although the individual COP of the chiller is considerably lower.


Author(s):  
J Harrod ◽  
P J Mago

Due to the soaring costs and demand of energy in recent years, combined cooling, heating, and power (CCHP) systems have arisen as an alternative to conventional power generation based on their potential to provide reductions in cost, primary energy consumption, and emissions. However, the application of these systems is commonly limited to internal combustion engine prime movers that use natural gas as the primary fuel source. Investigation of more efficient prime movers and renewable fuel applications is an integral part of improving CCHP technology. Therefore, the objective of this study is to analyse the performance of a CCHP system driven by a biomass fired Stirling engine. The study is carried out by considering an hour-by-hour CCHP simulation for a small office building located in Atlanta, Georgia. The hourly thermal and electrical demands for the building were obtained using the EnergyPlus software. Results for burning waste wood chip biomass are compared to results obtained burning natural gas to illustrate the effects of fuel choice and prime mover power output on the overall CCHP system performance. Based on the specified utility rates and including excess production buyback, the results suggest that fuel prices of less than $23/MWh must be maintained for savings in cost compared to the conventional case. In addition, the performance of the CCHP system using the Stirling engine is compared with the conventional system performance. This comparison is based on operational cost and primary energy consumption. When electricity can be sold back to the grid, results indicate that a wood chip fired system yields a potential cost savings of up to 50 per cent and a 20 per cent increase in primary energy consumption as compared with the conventional system. On the other hand, a natural gas fired system is shown to be ineffective for cost and primary energy consumption savings with increases of up to 85 per cent and 24 per cent compared to the conventional case, respectively. The variations in the operational cost and primary energy consumption are also shown to be sensitive to the electricity excess production and buyback rate.


2021 ◽  
Vol 11 (4) ◽  
pp. 1-54
Author(s):  
Mohammad Rishad Faridi ◽  
Saloni Sinha

Learning outcomes Appendix 1: Comic Frames A At the end of the case study discussion, students will able to as follows: Explain various growth strategies as a potential unicorn with the exponential growth mindset rather than linear growth mindset through adaptation of Massive Transformative Purpose (MTP) and Moonshot Thinking (MT). Demonstrate innovative and creative plans and ideas, with the ability to scale up in the circular economy. Review and summarize the power of Collaborative Innovation (CI). Compare and contrast different ways in dealing with Hedgehog and Fox style of leadership into the business. Appendix 2: Comic Frames B At the end of the case study discussion, students will able to as follows: Act with a growth strategy as a potential unicorn with the exponential growth mindset rather than linear growth mindset through adaptation of MTP and MT. Simulate innovative and creative plans and ideas, with the ability to scale up in the circular economy. Assess and leverage the power of CI. Decide and differentiate in dealing with Hedgehog and Fox style of leadership into the business. Case overview/synopsis Ankit Tripathi, was a compassionate 22-year-old, the typical lad from New Delhi, India, who seemed driven to change the world. His elder brother Atul Tripathi, a young, creative 25-year-old, was sat there next to him, beaming with pride and gratitude. Both brothers, being mechanical engineering graduates, had experienced the advancement of technology at the cost of Mother Earth. It pained them no end. It was the reason that Atul had refused to serve as an engineer in a government institution after graduating. The parents were shocked when Ankit followed suit. The brothers were poles apart in their personality and temperament, and it was rare to see them agree on anything in this way. Yet, they agreed to disagree with their parents and ventured into becoming entrepreneurs with a purpose and passion to salvage the environment. They had a vision, but without a proper roadmap, it would certainly be a tough game. Nevertheless, they boldly embarked upon their journey and established their start-up “Uneako” in 2019. “Uneako” was a calculated risk, taking into account family resistance (parents’ attitude/perception), personal conflicts (psychological), financial limitations (resources), shallow expertise (professionalism), social concern acceptability and low awareness (environment), government regulations (legalities/approvals), conflicts between brothers (personality issues), etc. Being from a nonbusiness family, the brothers had defied the wave of obstacles and challenges in daring to start their own business, putting at stake the hard-earned money of their father, Satendra Tripathi. Amidst so much social mockery, would Atul and Ankit succumb and become a laughing stock or would they find something that they could live and die for? Complexity Academic Level Appendix 1: Comic Frames A: This case has been particularly focused on undergraduate level students pursuing business or commerce programs. Especially those studying core courses, for example, entrepreneurial and strategic management. Appendix 2: Comic Frames B: This case has been particularly focused postgraduate-early stage or higher level students pursuing business or commerce programs. Particularly those specializing in entrepreneurial and strategic management courses. Also, can be taught in the entrepreneurial or start-up workshops. Supplementary materials www.pewresearch.org/topics/generation-z/ Paulynice. J.P., (2019) “From Idea to Reality: An Entrepreneur’s Guide to Meaningful Business Growth” Paulynice Consulting Group. Hardy.D., (2015) “The Entrepreneur Roller Coaster: It’s Your Turn to Join The Ride” Success Publishers. Wadhwa.V., Amla.I., Salkever.A., (2020) “From Incremental to Exponential” Berrett-Koehler Publishers. Sustainable Entrepreneurship: Business Success through Sustainability edited by Christina Weidinger, Franz Fischler, René Schmidpeter, Springer 2014. Teaching notes are available for educators only. Subject code CSS 3: Entrepreneurship.


2014 ◽  
Vol 21 (1) ◽  
pp. 111-126 ◽  
Author(s):  
Palaneeswaran Ekambaram ◽  
Peter E.D. Love ◽  
Mohan M. Kumaraswamy ◽  
Thomas S.T. Ng

Purpose – Rework is an endemic problem in construction projects and has been identified as being a significant factor contributing cost and schedule overruns. Causal ascription is necessary to obtain knowledge about the underlying nature of rework so that appropriate prevention mechanisms can be put in place. The paper aims to discuss these issues. Design/methodology/approach – Using a supervised questionnaire survey and case-study interviews, data from 112 building and engineering projects about the sources and causes of rework in projects were obtained. A multivariate exploration was conducted to examine the underlying relationships between rework variables. Findings – The analysis revealed that there was a significant difference between rework causes for building and civil engineering projects. The set of associations explored in the analyses will be useful to develop a generic causal model to examine the quantitative impact of rework on project performance so that appropriate prevention strategies can be identified and developed. Research limitations/implications – The limitations include: small data set (112 projects), which include 75 from building and 37 from civil engineering projects. Practical implications – Meaningful insights into the rework occurrences in construction projects will pave pathways for rational mitigation and effective management measures. Originality/value – To date there has been limited empirical research that has sought to determine the causal ascription of rework, particularly in Hong Kong.


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