Effects of wind energy utilization on long-run fuel consumption in remote Alaska microgrids

Thesis (M.S.) University of Alaska Fairbanks, 2019This paper presents an empirical analysis of the long-run reduction in diesel fuel consumption driven by wind energy utilization in remote Alaska electrical grids. Models control for other fuel consumption determinants including customer base and transmission and distribution system efficiency. Fourteen rural communities that integrated wind energy into their diesel powered electrical grids are analyzed within a dynamic panel framework using monthly utility data spanning sixteen years, from 2001 to 2017. An auto-regressive distributed lag approach is taken to address cointegration and presence of a unit root in the data. Long-run parameters are estimated for the full dataset as well as for four sub-samples to compare impacts on microgrids with high and low average renewable utilization and with large and small customer bases. Results indicate that fuel consumption is reduced by an estimated 68 gallons on average for each one percent increase in wind energy penetration on the electricity grid. Beyond 30% average penetration, however, additional wind energy generation leads to increased fuel consumption as turbine curtailment methods must be employed to maintain grid stability, indicating that this is a fuel-offset constraint point in low and medium penetration wind-diesel hybrid systems. High penetration-capable wind-diesel systems with energy storage capabilities may allow utilities to increase utilization rates beyond this threshold to capture additional fuel savings and carbon emissions offset.Southwest Alaska Municipal ConferenceIntroduction -- Background information -- Renewable integration into remote microgrids -- Wind energy basics -- Pre-estimation review of dataset -- Methodology -- Data -- Empirical results -- Results for the full sample -- Results for the penetration rates sub-samples -- Results for customer base sub-samples -- Discussion -- Conclusion -- References

Cost comparison of hydropower options for rural electrification in Rwanda

The decision to develop a hydropower plant depends on several factors, which cost is the most significant. This thesis, entitled "Cost comparison of hydropower options for rural electrification in Rwanda" intends to show that the use of a large number of mini hydropower plants for electrification of sparse rural areas in Rwanda is the least cost option when compared to installing either a single small or large hydropower plants. This is done by considering rural households to be randomly distributed and the model composed by 98 rural villages having three different population densities is used to test the validity of the hypothesis. Three different hydropower options providing the same level of service to rural households were used for the cost comparison. The relationship between the electrification cost per household versus the population density is deduced. Many distribution technologies can be used in rural areas and the accurate selection of the appropriate distribution technology is the main concern as it affects the cost of the whole distribution system. The rural network should be carefully designed so that the sizing of conductors to be used for LV and MV network is properly done at a low cost. The high distribution cost depends largely on the size of power to be delivered. Based on these findings, the cost comparison of mini, small and large hydropower schemes for rural electrification in Rwanda is discussed

독립 신재생 전력망의 에너지 모니터링 및 부하 고려 모델 개발

학위논문 (박사)-- 서울대학교 대학원 공과대학 기계항공공학부, 2017. 8. 안성훈.Demand for renewable energy sources has increased rapidly due to global warming. Since 1990, the renewable energy consumption ratio has increased among developed countries and the OECD average reached over 10% in 2015. Even in developing countries, an off-grid renewable power system has been implemented in rural areas to provide electricity. However, the power generation characteristics of renewable energy sources are so random that power outages occur frequently. In this research, an off-grid monitoring platform was developed and applied to an off-grid renewable energy system to overcome the instability of a renewable power system in rural areas. Our monitoring platform contains a customized real-time operating system with low-cost hardware for task management. The monitoring platform was capable of bidirectionally transmitting a data set via short message service or the internet. The transmitted data set was uploaded to a cloud system so that the off-grid system could be monitored with any platform. The energy consumption of manufacturing systems and renewable energy systems were modeled, and the operating conditions were simulated. The simulation results provided 1) the design guide for an off-grid system, 2) the failure rate with various scales of off-grid systems, and 3) the calculation method of operation times. Furthermore, the modeling method could be applied to various types of electric load conditions. Finally, an off-grid test bed was installed with our developed monitoring platform and four case studies were conducted: 1) a three dimensional printer, 2) a turning machine, 3) a band saw, and 4) a vaccine carrier, to verify the stability of the off-grid energy system with manufacturing processes. Comparison with previous research was also conducted, and the proposed simulation method provided a smaller scale of off-grid systems with stable operation.1 INTRODUCTION 1 1.1 OVERVIEW 1 1.2 STABILITY ISSUES IN RENEWABLE ENERGY SYSTEMS 7 1.3 STABILITY ISSUES AND MANUFACTURING PROCESSES 9 2 RENEWABLE ENERGY PRODUCTION MODEL 12 2.1 PV ENERGY PRODUCTION 12 2.2 WIND ENERGY PRODUCTION 19 2.3 BATTERY MODEL 23 2.4 COMBINING MODELS FOR A RENEWABLE ENERGY PLANT 28 2.5 OPERATION TIME CALCULATIONS 29 2.6 CONCLUSIONS 31 3 MANUFACTURING ENERGY CONSUMPTION MODEL 32 3.1 OVERVIEW 32 3.2 THEORETICAL BACKGROUNDS ON MANUFACTURING ENERGY CONSUMPTION 35 3.3 STANDARDIZED ENERGY CONSUMPTION MEASUREMENT PROCEDURE 43 3.4 RESULTS 51 3.5 ENERGY CONSUMPTION SIMULATOR 57 3.6 MACHINE LEARNING-BASED ENERGY CONSUMPTION MODELING 68 3.7 SUMMARY 75 4 ENERGY MODEL FOR RENEWABLE ENERGY AND MANUFACTURING PROCESSES 76 4.1 OVERVIEW 77 4.2 ASSUMPTIONS OF MODELS 79 4.3 GENERALIZED LOAD CONDITION 81 4.4 TEST BED FOR MODEL 84 4.5 MODELING RESULTS 88 4.6 SUMMARY 114 5 CONCLUSIONS 116 APPENDIX 118 6 BIBLIOGRAPHY 145 7 ABSTRACT IN KOREAN 154Docto

Decentralized renewable hybrid mini-grid based electrification of rural and remote off-grid areas of Bangladesh

Like many other developing nations Bangladesh has a very poor electrification rate especially in the rural areas. Millions of people here are excluded from the benefit of globalization because of no access to necessary electricity supply. This research work proposes decentralized renewable hybrid mini-grids as a potential approach for off-grid rural and remote area electrification in Bangladesh. Based on the available renewable resources an area specific resource map has been developed. The characteristics of the bottom of the economic pyramid market including customers’ attitude to switch from liquid fuel to mini-grid based electricity supply, expected load demand and their willingness to pay have been explored through a field study. Different combinations of hybrid systems have been designed and optimized using the HOMER micro-grid design software to cover the whole country. Results suggest that serving the required load over wider hours rather than having the same load concentrated in a short span of time can achieve better hybrid system performance. Initial capital subsidy of 40 percent along with 5 percent interest on loan has been applied in accordance with the renewable energy policy of Bangladesh government. Proposed optimized rice husk-diesel hybrid system in Rangpur, micro hydro-PV system in Rangamati, wind-PV system in Chakaria and PV-diesel system in coastal areas can produce electricity for USD 0.172/kWh, 0.291/kWh, 0.217/kWh and 0.316/kWh respectively while serving loads for 12 to 18 hours a day. Field data analysed by applying the dichotomous choice contingent valuation method revealed that customers are willing to pay maximum of USD 0.43/kWh. The value difference between the cost of electricity generation and the customers’ willingness to pay creates the opportunity to attract the private investors. Suitable business delivery models have been identified and explained for successful mini-grid business by private investment. Optimum hybrid systems have been standardized for replication and a sustainable business model has been suggested for scaling up this electrification approach

Energize the Base of the Pyramid!

In many countries of the Global South, energy infrastructure is holey, unreliable or simply not existent. This leads to different kinds of severe problems. Just to name a few: Family members, mostly women, spend hours every day to collect firewood for cooking. In many cases, they suffer under pulmonary diseases, because they have no access to clean cooking facilities. And companies are less productive without access to electricity. Students of the Joint International Master on Sustainable Development worked on energy access scale-up projects during their third semester at Leipzig University. In this semester, students are requested to work on an ''integration project'': integrating various aspects of sustainable development in a particular case study. The class of 2017 approached energy access from the interdisciplinary perspective of sustainable development, anchored however in the field of Economics and Management Science to ensure feasibility of their work. This present edition of Studies in Infrastructure and Resources Management looks at their work in two different energy access scale-up projects in the sub-Saharan countries Nigeria and Senegal

太陽光発電による電化と教育成果に対する含意 : 南アジアにおける実証的知見

広島大学(Hiroshima University)博士(学術)Doctor of Philosophydoctora

A post-installation analysis of solar PV-diesel hybrid systems for school electrification in Sabah, Malaysia

Alternative energy technology has been used widely in rural electrification program (REP) all over the world for many years now. Renewable energy sources, such as solar, wind and biomass, are the preferred choices given the abundant resources available on site and the sophistication of the technologies involved. Combinations of two or more of the resources, together with an energy storage system and occasionally a conventional energy generator, create a hybrid system, which is reliable and durable. In Malaysia, solar photovoltaic (PV) base systems, implemented on a large scale, can provide round-the-clock electricity services for areas that are inaccessible by the electricity grid network. One of Malaysia s REP initiatives is solar PV-diesel hybrid systems for 160 schools in rural Sabah. The systems have been in operation for several years, but studies in the program are limited. Thus, understanding the system operation and functional is a highly valuable experience and lessons can be learned for implementation of the rural electrification program (REP). The overall aim of the research is to evaluate the REP in social, organizational, technical and economic aspects of the program that the findings can facilitate the stakeholders, such as the policy makers and implementers for current and future approaches, measures and decisions on REP activities and initiatives in Malaysia. This thesis has described the approaches on investigating the rural school s electrification program in Sabah. Analysis of system operation and function is conducted by examining and evaluating the recorded data from the system. A set of technical indicators is introduced in the form of system performance indicators and system reliability indicators. Furthermore, comparisons are made between the actual system operation and the optimum system configuration based on the actual data of the renewable energy resources, electricity energy consumption and costs in installation and operation. A field study was conducted at fifteen rural schools that use the solar PV system to determine the effectiveness of the program in transforming the rural schools to better learning environments and livelihoods. The findings indicate that most system components were found to be in good operation, and the operation of the solar PV system agreed to the indicators of system performance and system reliability. Additionally, the system reliability indicators can be seen as a vital tool not only to identify the values of the system capacity but also for prediction measures in analysing the durability of each component. The analysis of the actual system operation provides optimum values in terms of technical indicators, whereas the optimized system shows economic advantages. The findings show a high degree of responses from the end users in the level of satisfaction, appreciation, motivation and academic excellence. Nevertheless, several improvements are required to enhance the sustainability elements of the REP, especially from the organizational and governance perspectives. These includes effective coordination among the rural development-related agencies, the improvement on the transition between installation and maintenance work, efficient reporting process and training and awareness program need to be extended to every end user for sustainability in information and knowledge