Capacitor Motor as Low-Power, Low-Speed Single-Phase Generator

In this paper, some results of experiment on modification of induction motor into generator are described. Not as usually done on three-phase motor, the modification has been done on capacitor motors normally supplied with single-phase source. The resulted induction generator should be able to self-excite and has been intended for low-power, low-speed applications. These applications are prospective for example in rural renewable energy generations and as motors for some special electric vehicles. Machine modification instead of total design-production or new machine acquisition is considered more appropriate for remote rural electrification. Distance and transportation difficulties, unavailability of nearby machine industry, lack of human resources with ‘high-tech savvy', besides the low purchasing power of population in remote rural areas are some reasons behind the consideration. Experiment results indicated that voltage generation up to nominal value is not always easy to attain in a capacitor motor, even when functioning beyond its synchronous speed. An additional pre-charged capacitor should be used to initiate voltage generation. During start-up, load and the pre-charged capacitor had to be removed from generator to avoid capacitor discharge. Load could then be added gradually once generator approached its nominal output value. It was also shown that in order to generate power the generator must be rotating over its synchronous speed. The resulted frequency values did not vary linearly to the rotation speed and the obtained efficiency was still low

Capacitor Motor as Low-Power, Low-Speed Single-Phase Generator

In this paper, some results of experiment on modification of induction motor into generator are described. Not as usually done on three-phase motor, the modification has been done on capacitor motors normally supplied with single-phase source. The resulted induction generator should be able to self-excite and has been intended for low-power, low-speed applications. These applications are prospective for example in rural renewable energy generations and as motors for some special electric vehicles. Machine modification instead of total design-production or new machine acquisition is considered more appropriate for remote rural electrification. Distance and transportation difficulties, unavailability of nearby machine industry, lack of human resources with ‘high-tech savvy’, besides the low purchasing power of population in remote rural areas are some reasons behind the consideration. Experiment results indicated that voltage generation up to nominal value is not always easy to attain in a capacitor motor, even when functioning beyond its synchronous speed. An additional pre-charged capacitor should be used to initiate voltage generation. During start-up, load and the pre-charged capacitor had to be removed from generator to avoid capacitor discharge. Load could then be added gradually once generator approached its nominal output value. It was also shown that in order to generate power the generator must be rotating over its synchronous speed. The resulted frequency values did not vary linearly to the rotation speed and the obtained efficiency was still low

The current infrastructure conditions and the problems relating to it : focusing on Rietkol, Delmas, Mpumalanga, South Africa

The government must involve the community within the infrastructure development in order to create, operate and maintain it. This is “participatory democracy”, “participatory development” and “people centred development”. It will implement the empowerment of the rural community through inspiration of community, public participation and a democratic culture. Through research, debate and data analysis the researchers concluded that the most important type of infrastructure is water supply. Additionally, sanitation, electricity and telecommunication follow on its heels, for development of infrastructure for this particular community.Paper presented at the 3rd Global Virtual Conference 2015 (GV-CONF 2015), THOMSON, Slovakia, April 6-10, 2015. Remove selectedhttp://www.gv-conference.comhb201

Electric Energy Access in Bangladesh

This paper represents the overall electrical energy profile and access in Bangladesh. In the recent past Bangladesh has been experiencing shortage of electricity, and about 42 % of population no access to the electricity. The electricity consumption has rapidly increased over last decade. The demand and consumption will intensify in the remote future as overall development and future growth. To set “vision 2021” of Bangladesh; government of Bangladesh has devoted to ensuring access of affordable and reliable electricity for all by 2021. In the modern time, energy is the vital ingredient for socioeconomic growth in the developing country i.e., alleviating poverty. Along with electricity access in Bangladesh strived to become middle income country by 2021. Bangladesh has experienced that energy consumption inclines to increase rapidly when per capita income researches between US$1,000 and US$ 10,000, and a country’

Mapping the least-cost option for rural electrification in Burkina Faso: Scaling-up renewable energies

This report describes the current status and limitations of the power sector in Burkina Faso and develops a new methodology that through spatial analysis processes aims to provide a possible pathway for universal electricity access through a sustainable energy mix. Two percent of the rural population in Burkina Faso has access to electricity and supply is lacking at many social structures such as schools and hospitals. Energy access achievements in Burkina Faso are still very modest. The rural electrification strategy for Burkina Faso is scattered in several electricity sector development policies: there is a need of defining a concrete action plan. Planning and coordination between grid extension and off-grid electrification programmes is essential to reach a long-term sustainable energy model and to avoid high unnecessary infrastructure investments. This report describes the development and the results obtained with a dynamic planning tool to support national government and development partners in defining an alternative electrification plan. Currently, the common national policy for electrification is dominated almost exclusively by grid extension with the government subsidising fossil fuel electricity production. However, the results of our analysis suggest that an electrification plan mainly based on further grid extension becomes inefficient and unsustainable in order to reach the national energy access targets. Our results also suggest that Burkina Faso’s rural electrification strategy should be driven by distributed minigrids powered by local renewable resources. We find that this approach would connect more people to power more quickly, and would reduce imported fossil fuel dependence/consumption that would otherwise be necessary for grid extension options.JRC.C.2-Energy Efficiency and Renewable

Free vibration of symmetric angly-plane layered truncated conical shells under classical theory

Truncated conical shell finds wide ranging of engineering applications. They are used in space crafts, robots, shelters, domes, tanks, nozzles and in machinery devices. Thus, the study of their vibrational characteristics has long been of interest for the designers. The use of the lamination for the structures leads to design with the maximum reliability and minimum weight. Moreover, the study of free vibration of laminated conical shells has been treated by a number of researchers. Irie et al. (1982) studied free vibration of conical shells with variable thickness using Rayleigh-Ritz method of solution. Wu and Wu (2000) provided 3D elasticity solutions for the free vibration analysis of laminated conical shells by an asymptotic approach. Wu and Lee (2001) studied the natural frequencies of laminated conical shells with variable stiffness using the differential quadrature method under first-order shear deformation theory (FSDT). Tripathi et al. (2007) studied the free vibration of composite conical shells with random material properties of the finite element method. Civalek (2007) used the Discrete Singular Convolution (DSC) to investigate the frequency response of orthotropic conical and cylindrical shells. Sofiyez et al. (2009) studied the vibrations of orthotropic non-homogeneous conical shells with free boundary conditions. Ghasemi et al. (2012) presented their study of free vibration of composite conical shells which was investigated under various boundary conditions using the solution of beam function and Galerkin method. Viswanathan et al. (2007, 2011) studied free vibration of laminated cross-ply plates, including shear deformation, symmetric angle-ply laminated cylindrical shells of variable thickness with shear deformation theory using the spline collocation method. In the present work, free vibration of symmetric angle-ply laminated truncated conical shells is analyzed and displacement functions are approximated using cubic and quantic spline and collocation procedure is applied to obtain a set of field equations. The field equations along with the equations of boundary conditions yield a system of homogeneous simultaneous algebraic equations on the assumed spline coefficients which resulting to the generalized eigenvalue problem. This eigenvalue problem is solved using eigensolution technique to get as many eigenfrequencies as required. The effect of circumferential mode number, length ratio, cone angle, ply angles and number of layers under two boundary conditions on the frequency parameter is studied for three- and five- layered conical shells consisting of two types of layered materials

Accomplishing rural electrification for over a billion people: Approaches towards sustainable solutions

Access to electricity appears to be a prerequisite to materialize social, economic, and human development in the underprivileged rural areas. However, 1.1 billion rural people in the world, almost all of them living in developing countries, still do not have access to electricity. Although the rural electrification process poses more challenges than urban electrification, rural areas are blessed with abundant and relatively evenly distributed renewable energy resources. To facilitate electricity access to this huge population, it is essential to deal with the rural electrification task by considering its challenging features and the potential merits of renewable resources. The objective of this thesis is to present policy and techno-economic frameworks for sustainable and accelerated rural electrification for over a billion people in developing countries. This thesis considers grid expansion as the primary option for rural electrification, and renewable resource based off-grid options were considered as the alternative where grid expansion is not feasible. Grid-based rural electrification policies were examined by focusing on one case program (the Bangladesh rural electrification program) in light of challenges that are generic for developing countries. The assessment of the potentials and techno-economic viability of renewable resources were performed by utilizing analytical methodologies and well-established computer tools (HOMER and RETScreen). The evaluation of choices among rural electrification alternatives has been illustrated with the help of the Stochastic Multicriteria Acceptability Analysis (SMAA) tool. The evaluation methods and tools are illustrated by employing case data obtained mainly from Bangladesh. This thesis observed that some key policy elements influence the performance of a grid-based rural electrification program. These policy elements guide the rural electrification program towards success through addressing distinct rural electrification challenges. Agricultural residues have the potential to generate electricity to meet household-level demands in rural areas of many developing countries. Hybrid biogas and solar resources can serve both clean-cooking and electricity loads in rural households with achieving benefit (saving) more than the cost. The multicriteria decision support technique enables a rural electrification program to choose decision options from different alternatives based on sustainability criteria.