scholarly journals Progress for On-Grid Renewable Energy Systems: Identification of Sustainability Factors for Small-Scale Hydropower in Rwanda

Energies ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 826
Author(s):  
Geoffrey Gasore ◽  
Helene Ahlborg ◽  
Etienne Ntagwirumugara ◽  
Daniel Zimmerle

In Rwanda, most small-scale hydropower systems are connected to the national grid to supply additional generation capacity. The Rwandan rivers are characterized by low flow-rates and a majority of plants are below 5 MW generation capacity. The purpose of this study is to provide a scientific overview of positive and negative factors affecting the sustainability of small-scale hydropower plants in Rwanda. Based on interviews, field observation, and secondary data for 17 plants, we found that the factors contributing to small-scale hydropower plant sustainability are; favorable regulations and policies supporting sale of electricity to the national grid, sufficient annual rainfall, and suitable topography for run-of-river hydropower plants construction. However, a decrease in river discharge during the dry season affects electricity production while the rainy season is characterized by high levels of sediment and soil erosion. This shortens turbine lifetime, causes unplanned outages, and increases maintenance costs. Further, there is a need to increase local expertise to reduce maintenance cost. Our analysis identifies environmental factors related to the amount and quality of water as the main current problem and potential future threat to the sustainability of small-scale hydropower. The findings are relevant for energy developers, scholars, and policy-makers in Rwanda and East Africa.

2010 ◽  
Vol 90 (3) ◽  
pp. 189-206 ◽  
Author(s):  
Mila Pavlovic ◽  
Rajko Golic ◽  
Dejan Sabic

The territory of the municipality of Mali Zvornik is, from the aspect of morphology and spatial-functional structure, a heterogeneous area. It is located in the valley of the Drina River and in hilly-mountainous part of Podrinjske mountains. The area of the municipality is 184 km?, with 14076 inhabitants (2002). The importance of water resources for the development of the municipality, particularly of the hydropower plant (HPP) ?Zvornik?, is analyzed in this paper. Inadequate use of hydro-energetic potential, possibilities for construction of new hydropower plants and economic reasons for their construction are also emphasized. The priorities of the development of hydraulic engineering are defined in relation to morphological and hydrological conditions. They refer to increase of power of the HPP ?Zvornik? and construction of small-scale hydropower plants in hilly-mountainous part of municipality. Considering depopulation processes in the villages of Mali Zvornik, hydraulic engineering, together with agriculture, forestry, exploitation of mineral goods and tourism, can be one of the factors of demographic and economic revitalization of this area.


Water ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 2522
Author(s):  
Isabel Boavida ◽  
Filipa Ambrósio ◽  
Maria João Costa ◽  
Ana Quaresma ◽  
Maria Manuela Portela ◽  
...  

Downstream of small-scale hydropower plants (SHPs), the intensity, frequency and persistence of hydropeaking events often cause an intolerable stress on fish of all life stages. Rapid increases in flow velocity result in fish avoiding unstable habitats and seeking refuge to reduce energy expenditure. To understand fish movements and the habitat use of native Iberian cyprinids in a high-gradient peaking river, 77 individuals were PIT tagged downstream of Bragado SHP in the North of Portugal. Tagged fish species included Pseudochondrostoma duriense and Squalius carolitertii. Fish positions were recorded manually on two different occasions: during hydropeaking events (HP) and without hydropeaking events (NHP). From the 77 tagged fish, we were able to record habitat use for 33 individuals (20 P. duriense and 13 S. carolitertii) in a total of 125 relocations. Fish species were distributed along the river reach with high density in the upstream area in the vicinity of the SHP tailrace, in particular during HP. Fish locations were associated with velocity for P. duriense and S. carolitertii. The latter tended to use faster flowing waters than P. duriense. Our findings on the habitat use in peaking rivers are a valuable tool to help in the selection and design of mitigation measures.


2019 ◽  
Vol 2 (2) ◽  
pp. 145-148
Author(s):  
A. M. Shiddiq Yunus ◽  
Musrady Mulyadi ◽  
Apollo Apollo

Mitigation of catastrophic impacts of exhausted pollutants from conventional based power plants could be done by extensively used of renewable energy-based power plants. One of the promising renewable-based power plants that already have technology maturity is hydropower. However, large scale hydropower is based on an appropriate site and not economically effective for isolated and remote small communities. As anticipation, to fulfill the power requirements of these communities, micro-hydropower plants (MHPPs) are applied due to its inexpensive capital and low maintenance cost. Normally, MHPPs projects are finalized from civil construction to powerhouse. A simple trash filter is usually located before the intake of the penstock. This simple trash filter usually causes a problem related to trash collection that blocks the water debit into the penstock intake. The low debit, might cause the turbine's rotation will be reduced which in turn downgrade the voltage and frequency. Low voltage and frequency might harm consumers. In this paper, a new control mechanism based on Arduino Mega of automatic trash removed is introduced.


2015 ◽  
Vol 17 (2) ◽  
pp. 87
Author(s):  
Mochamad Nasrullah ◽  
Wiku Lulus Widodo

ABSTRAK PERHITUNGAN BIAYA OPERASI DAN PERAWATAN PLTN SKALA BESAR DAN KECIL. Biaya pembangkit PLTN terdiri dari tiga komponen, yaitu biaya investasi, bahan bakar dan operasi perawatan (O & M). Besarnya biaya O&M pada PLTN besar dan kecil tidaklah sama. Studi ini bertujuan untuk menghitung biaya O&M PLTN skala besar dan kecil dengan mempertimbangkan parameter teknis dan ekonomis yang diambil dari berbagai data sekunder dan sumber lainnya. Studi dilakukan menggunakan data dari PLTN jenis PWR dengan daya 1343 MWe untuk PLTN ukuran besar dan daya 90 MWe untuk PLTN ukuran kecil. Asumsi digunakan tingkat eskalasi sebesar 5%, faktor kapasitas 90%. Metodologi yang digunakan adalah menghitung dengan spreadsheet yang meliputi skala masing-masing komponen O&M. Hasil perhitungan menunjukkan biaya O & M jika dihitung dengan satuan juta US$/tahun, maka biaya O&M PLTN 1343 MWe sebesar 99,21 juta US$/tahun lebih mahal dari PLTN 90 MWe sebesar 45,13 juta US $/tahun. Namun jika biaya O & M PLTN 1343 MWe dihitung dengan satuan mills $/kWh, maka hasilnya  sebesar 9,37 lebih murah dibandingkan dengan PLTN 90 MWe yaitu sebesar 63,70 mills $/kWh. Hal ini berarti semakin kecil ukuran kapasitas dayanya maka biaya operasi dan perawatannya semakin mahal. Penyebab perbedaan biaya operasi dan perawatan antara PLTN skala besar dan kecil, adalah kapasitas daya, faktor kapasitas, jumlah personal yang bekerja pada biaya administrasi umum pegawai dan manajemen, operasi pembangkit tahunan, biaya tenaga kerja offsite. Kata kunci : Biaya operasi dan perawatan, PLTN, LEGECOST ABSTRACT CALCULATION OF OPERATION AND MAINTENANCE COST FOR LARGE AND SMALL SCALE NPP. The generation cost of nuclear power plant consists of three components:  investment costs, fuel cost operation and maintenance (O&M) cost. O&M costs in the large scale of NPP is different from small scale NPP. The objective of this study are to calculate the O&M cost of large NPP and small NPP by considering technical and economic parameters from secondary data and  other references. This study uses 1343 MWe PWR data for large NPP and 90 MWe PWR for small NPP. The assumptions are 5% escalation level and 90% capacity factor. The methodology for calculation using spreadsheet with scaling methods for each O&M components. The results shows that the O &M cost if calculated in units of million US$/year, the O&M cost of NPP 1343 MWe is US$million 99.21/ year which is more expensive than the O&M cost of NPP 90 Mwe which is only US$million 45.13/ year.  But if the cost of O&M 1343 MWe nuclear power plant unit is calculated in units of mills $/kWh, the result shows that the O&M cost is 9.37 mills $/kWh which is less than the 90 MWe NPP which reaches $ 63.70 mills/kWh. The conclusion is  lower NPP capacity  has higher O&M cost. Different O&M cost is caused by power capacity, capacity factor, the amount of worker on site staff, the annual net generation and the offsite technical support. Keywords: Operation and maintenance cost, NPP, LEGECOST 


2013 ◽  
Vol 18 (9) ◽  
pp. 29-35
Author(s):  
Marcin Bukowski

Abstract Polish accession to the EU was followed by a need of adaptation of Polish legislation to the European requirements, also with regard to the energetic sector. The need of achieving 15% share of electric power from renewable sources in the total energy consumption till the year 2010 is a consequence of this decision. This target may be achieved in Polish conditions based on water and wind energy and from biomass combustion. The paper presents the influence of hydrologic conditions and technical parameters on the amount of produced energy. Factors affecting energy production in small hydropower plants were analysed. The formula was proposed to describe the effect of water flow in a river on energy production in small hydropower plants.


2021 ◽  
Vol 17 (2) ◽  
pp. 95-110
Author(s):  
Agustia Larasari ◽  
Jessica Sitorus ◽  
Moh. Bagus Wiratama Asad ◽  
Ary Firmana

One of the utilizations of a multipurpose dam that has socio-economic value during its operation iselectricity generation. The addition of a hydropower component to a PPP project is quite a challenge due to substantial uncertainty related to hydrological aspects that will impact electricity production and revenue, as well as high initial investment costs for generating units. This study aims to map the technical potential of hydropower and evaluate the economic feasibility of hydropower in the Merangin Dam PPP Project. The potential for power and energy generation is obtained through simulations of the hydropower operation for 19 years using hydrological data, HEC-HMS model generated-data, and dam engineering design. According to the results, the technical potential of hydropower can produce, on average, power of Pp = 103.8 MW during peak load, Pb = 98.53 MW during base load, and total energy of 636.66 GWh/year. The economic potential is evaluated through social cost-benefits analysis (SCBA) by estimating the additional benefits obtained from the hydropower compared to the PPP structure of the Merangin Dam without hydropower. Through SCBA, the addition of hydropower to the Merangin Dam PPP structure has an EIRR value of 35.24%, NPV of Rp. 2.104.212.122.723,- and BCR = 3.06. Based on these indicators, the provision of hydropower plants is considered economically feasible because the benefits that will be generated and obtained by the community are higher than the economic costs incurred.Keywords: Technical potential, economic feasibility, hydropower plant, multipurpose dam, PPP


Water ◽  
2021 ◽  
Vol 13 (17) ◽  
pp. 2419
Author(s):  
Vidosava Vilotijević ◽  
Uroš Karadžić ◽  
Radoje Vujadinović ◽  
Vuko Kovijanić ◽  
Ivan Božić

Designing a small hydropower plant (SHPP) necessitates fulfillment of energy and ecological constraints, so a well-defined design flow is of the utmost significance. The main parameters of each SHPP are determined by appropriate techno-economic studies, whereas an improved approach to defining more precise SHPP installed parameter is presented in this paper. The SHPP installed parameter is the ratio of the design flow and averaged perennial flow obtained from the flow duration curve at the planned water intake location. Previous experiences in the design of SHPPs have shown that the SHPP installed parameter has a value in a wide range without the existence of an unambiguous equation for its determination. Therefore, with this aim, the thirty-eight (38) small watercources in the territory of Montenegro, denominated for the construction of SHPPs, have been investigated. SHPPs are divided into two groups depending on the installed capacity and the method of calculating the purchase price of electricity. For both groups, the range of SHPP installed parameter is determined according to the technical and economic criteria: the highest electricity production, the highest income, net present value (NPV), internal rate of return (IRR), and payback period (PB).


2018 ◽  
Vol 3 (1) ◽  
pp. 39
Author(s):  
. Mardianto

Agricultural land conversion occurs mostly in big cities in Indonesia and also occurs in small villages and towns on a small scale but not much has been done by the study. This study was linked to detect factors affecting land conversion in Kota Solok. This research was conducted by survey method. Sampling is done by simple random sampling with balanced amount. The data collected in this study includes primary data and secondary data. The analysis is done by description using percentage of respondent's level of achievement (tcr). The result of the analysis shows that the conversion of paddy fields in Solok City is mostly done by individual buyers, the internal factor which has the greatest effect on the conversion of paddy fields in Solok City is the economic condition, while the external factor is caused by the population growth and the policy caused by the weakness of policy control which government apparatus.


2019 ◽  
Vol 86 ◽  
pp. 00008 ◽  
Author(s):  
Agnieszka Operacz ◽  
Bartosz Szeląg ◽  
Mads Grahl-Madsen

In hydropower plants benefits depends on available flow. The paper presents a hybrid model for forecasting the operation of a hydropower plant, including the production of electricity. The possibility of mathematical modeling was chosen to show connections between observed in the past hydrological conditions (available flow) and energy deliver in the future. The available flow which is not enough for start turbines was forecasting by logistic regression model. The opposite situation when the flow starts turbine to produce energy, regression models (the support vector machines SVM, random forest RF, k nearest neighbour k-NN) were used. Results from hybrid model were compared with chosen data-mining methods. The possibility of forecasting of the length of periods when hydropower plant will be working could be very useful. It provides the prognosis of energy value which could be produced from hydropower plant. From the investors’ point of view the economic justification for the execution of the project based on the future energy producing could be a main criteria to realize or buy/sell hydropower plant. Also the secondary importance could be a possibility of planning review and maintenance work. Knowledge of power plant working periods could be a base for assessing a potential production from hydropower plant.


Challenges ◽  
2020 ◽  
Vol 11 (2) ◽  
pp. 17 ◽  
Author(s):  
Ourania Tzoraki

In arid and semi-arid parts of the world, river exploitation is intensive, involving water storage for irrigation or hydropower generation. In Greece, 100 small hydropower plants (SHPs) take advantage of less than 10% of the hydropower potential of low flow streams (<2 m3/s), a very small amount in relation to the 70% of the European Union. The energy policy of complete decarbonization of the country by 2023 on a national scale opens the road for new investments in SHP projects, especially in intermittent-flow streams of the Greek islands. Simulated flows by the Modello Idrologico SemiDistribuito in continuo (MISDc model) are used to construct the annual flow duration curve (FDC) to study and assess the hydropower potential of an intermittent stream (Tsiknias river, Lesvos, Greece). For Tsiknias River, but also for six other intermittent-flow rivers of Crete island, the capacity factor (CF), which represents the mean annual power of the hydropower plant, should remain >75% to exploit the river’s potential. The FDC and CF are essential in designing SHP projects in intermittent-flow streams with long no-flow periods. The development of public participatory approaches and a closer cooperation among policy makers and stakeholders should work to promote hydropower exploitation and accelerate licensing procedures.


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