DSpace Collection: Thesis - Electrical Power Engineering

ASSESSMENT OF MICRO HYDRO POWER POTENTIAL OF SELECTED ETHIOPIAN RIVERS- A CASE STUDY IN THE NORTH-WEST PART OF THE COUNTRY

Mon, 27 May 2013 08:01:33 GMT

Title: ASSESSMENT OF MICRO HYDRO POWER POTENTIAL OF SELECTED ETHIOPIAN RIVERS- A CASE STUDY IN THE NORTH-WEST PART OF THE COUNTRY

Authors: Abebe, Tilahun

Abstract: Ethiopia is a country situated in the horn of Africa with a total population of 80 million of which 85% is living in rural areas where access to modern electricity is difficult, with electrification status negligible and being < 1% [2, 3]. These communities are settled farther away from the national grid and are sparsely populated which makes extending the national grid to them uneconomical because of the high cost of transmission and the very low load factor. However, improving the life style of the population as well as the economy of a country will be difficult without energy especially modern energy systems. For their day to day life these rural people are using kerosene, fire wood, cow dung and other traditional fuels which have the problem of high and day-by-day increasing price and negative environmental effect because of deforestation and soil erosion. However, if these communities are supplied with modern electricity from renewable energy resources, their life will be improved and the environment will be protected from damage and this is the basic idea for this thesis. In this thesis, assessment of micro hydropower (MHP) potential of selected rivers is done. The selected rivers are, “Jedeb”, “Temcha” and “Gilgel_Abay” for the communities living in the villages called “Belem‟na”, “Muketin” &“Yewubesh”, and “Killaj” respectively. Some of the data for this work are gathered from Ministry of Water & Energy of Ethiopia (MoWE) and the rest is collected/ measured from field work. Some part of the data from MoWE is treated with ArcGIS software. Local load estimation for each of the villages is done with lighting, cocking and radio &TV loads considered as home loads and pumping, church and school lighting considered as general community loads and all these loads are scheduled appropriately. HOMER is used for designing and simulating the general system of each village. The simulation result shows that the generated electricity is more than enough to supply the local loads considered with an excess energy of at least 50% of the generated energy and this shows that the systems are tolerable for this amount of demand increase in the future.

INVESTIGATION AND ANALYSIS OF ASHEGODA WIND FARM INTEGRATION IMPACT ON ETHIOPIAN GRID

Tue, 05 Feb 2013 04:32:52 GMT

Title: INVESTIGATION AND ANALYSIS OF ASHEGODA WIND FARM INTEGRATION IMPACT ON ETHIOPIAN GRID

Authors: Hiwot, Eshetu

Abstract: Ethiopian electric power corporation is under implementation stage to integrate wind power to exiting grid system which contains mainly hydro generators. Integration of wind power plant with grid system has many challenges that need to be studied thoroughly to identify major problems. The major problems induced by the wind farm depend on level of penetration. In this thesis work operational impacts associated with “Ashegoda Wind Farm (AWF)” integration has been studied, mainly variability, predictability and steady state stability impacts. The variability and predictability impacts have been studied using statistical method on the basis of data supplied from wind project office of “Ethiopian Electric Power Corporations”. Ashegoda wind farm increases the variability of the system load characteristics in case of hourly and thirty minute load. As per the result of the stability study, there is a steady state voltage stability impact under contingency cases. However, in base case, there is no any stability impact. Along with the stability analysis, one of possible solutions, that is, managing the transmission line capacity have been suggested and discussed. In addition to variability impact, predictability impact also studied by developing a wind power forecasting model. Different models have been developed and the one with best forecast accuracy selected on the basis of MAE and compared with persistence model considering as a base model.

DESIGN OF A PHOTOVOLTAIC-WIND HYBRID POWER GENERATION SYSTEM FOR ETHIOPIAN REMOTE AREA

Thu, 10 May 2012 10:30:08 GMT

Title: DESIGN OF A PHOTOVOLTAIC-WIND HYBRID POWER GENERATION SYSTEM FOR ETHIOPIAN REMOTE AREA

Authors: Gelma, Boneya

Abstract: This thesis presents the design of a hybrid electric power generation system utilizing both wind and solar energy for supplying model community living in Ethiopian remote area. The work was begun by investigating wind and solar energy potentials of the desired site, compiling data from different sources and analyzing it using a software tool. The data regarding wind speed and solar irradiation for the site understudy are collected from the National Metrological Agency (NMA) and analyzed using the software tool HOMER. The results related to wind energy potential are given in terms of the monthly average wind speed, the wind speed PDF, the wind speed CDF, the wind speed DC, and power density plot for the site. Whereas the solar energy potential, has been given in the form of solar radiation plots for the site. According to the results obtained through the analysis, the site has abundant solar energy potential and the wind energy potential is unquestionably high enough to be exploited for generating electric energy using wind turbines with low cut-in wind speed. The design of a standalone PV-wind hybrid power generating system has proceeded based on the promising findings of these two renewable energy resource potentials, wind and solar. Electric load for the basic needs of the community such lighting, water pumping, a radio receiver, flour mill and medical equipment for a health clinic has been suggested. The simulations and design has been carried out using the HOMER software. By running the software the simulation results which are lists of power supply systems have been generated and arranged in ascending order according to their net present cost. Sensitivity variables, such as range of wind speed, solar radiation, PV panel price and diesel price have been defined as inputs into the software and the optimization process has been carried out repeatedly for the sensitivity variables and the results have been refined accordingly

OPTIMAL POWER GENERATION EXPANSION PLANNING FOR ETHIOPIAN ELECTRIC POWER SYSTEM

Fri, 04 May 2012 08:09:00 GMT

Title: OPTIMAL POWER GENERATION EXPANSION PLANNING FOR ETHIOPIAN ELECTRIC POWER SYSTEM

Authors: Girmaw, Teshager

Abstract: This thesis presents an optimal power generation expansion planning model that considers the growth of fuel prices and its fluctuation, power risks, benefits of carbon-trading in generation expansion decision. The developed model is applied to Ethiopian Electric Power System for ten years in the future. In Ethiopian electric power system, the electric demand has been running ahead of supply. In addition, the growth of fuel price can affect the country economy. Moreover, since the dominant energy consumption is covered by firewood and charcoal (both take a share of 78% of national energy balance), the environmental degradation and deforestation is being continually increased. Therefore, to minimize these problems, a multi-objective model preceded by electric demand forecasting is developed. Attributes, which are considered in the work, include investment and generation cost of the power generating units, the environmental impacts, the amount of imported fuels and carbon-trading benefit. The model is simulated by written code in MATLAB work space. The MATLAB code simulates the model to outcome the generation of each power plant at minimized cost incurred for building the power plants, production of electric energy and fuel to be imported. The forecasted demand shows that the average demand annual growth rate is 34.78% by scenario-1 and 31.98% by scenario-2. EEPCo plan is annually deviated from the forecasted values by an average of 32% and 27% with respect to scenario-1 and scenario-2 respectively. The investment and generation cost expended is an average of 0.0112 USD to produce a kWh electric energy for extra power generation in case of carbon trade consideration in generation expansion planning. It is very low compared to the cost of an average of 0.111 USD to produce a kWh electric energy by regular approach like model-2. Oil fuel for power plants and cooking in urban areas comes to nil in the proposed planning periods.