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Research Article
Development of an Automated Ground Solar Radiation System for Enhancing Energy Supply in Zimbabwe
Issue:
Volume 14, Issue 1, February 2025
Pages:
1-22
Received:
20 January 2025
Accepted:
8 February 2025
Published:
21 March 2025
Abstract: A gap in Zimbabwe’s energy supply and demand can be filled by extensive incorporation of solar energy in the country’s current energy mix. The amount of solar energy to be harvested at any site varies in quantity with time and location following variations in the received solar radiation. This research was conducted to develop an automated system which uses solar radiation equations, geospatial techniques and python programming to estimate received solar radiation in Zimbabwe. To validate the system performance a comparison between system results and ground measured radiation was conducted using statistical metrics such as Pearson correlation (R), Coefficient of Determination (R2), Root Mean Square Error (RMSE) and Normalised Mean Absolute Error (NMAE). Suitable sites for solar harvesting were determined using Multi-criteria Decision Making (MCDM) and weighted overlay analysis. The developed system determined temporal evolution in ground solar radiation from sunrise to sunset, and hours before 08:21am had radiation values below 0.9Mj. From 9:21am to 14:21pm radiation values were above 1.5Megajoules (Mj) with peak radiation of 2.13Mj at 12:21pm. The computed statistical metrics showed that there was a good agreement and better performance as most months had a Person correlation above 0.57, RMSE less than 2.7 and NMAE less than 1.7. The months of May, June and July were the peak of winter season evidenced by less radiation intensities between 14Mj and 18.5Mj whilst September to March had higher radiation ranging 20Mj to 26Mj. From the conducted site suitability analysis, 0.77% was highly suitable, 30.67% was suitable, and 5.1% moderately suitable and 63.45% falls under restricted areas. By consideration of only 1% of the highly suitable areas while using a solar system with 10% efficiency, 197.41 Gigajoules (GJ) can be harvested in Zimbabwe. Therefore, this sustainable energy can be used to supply Zimbabwe and bridge the current energy gap.
Abstract: A gap in Zimbabwe’s energy supply and demand can be filled by extensive incorporation of solar energy in the country’s current energy mix. The amount of solar energy to be harvested at any site varies in quantity with time and location following variations in the received solar radiation. This research was conducted to develop an automated system w...
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Review Article
Solar Based Irrigation System Application as an Option for Energy Source for Irrigation Water Management in Ethiopia: A Review
Issue:
Volume 14, Issue 1, February 2025
Pages:
23-28
Received:
7 March 2025
Accepted:
11 April 2025
Published:
9 May 2025
Abstract: Electricity is the most cost-effective and efficient energy source for pumping water, but farmers with small, scattered plots might not have access to it. To raise water for irrigation, farmers rely on diesel or gasoline pumps, which is expensive and non-sustainable. For better management of water and economic benefit, considering another option for irrigation such as the solar pumped irrigation system could be important. Solar power enhances efficiency, productivity, and sustainability in agricultural operations in addition to offering a clean alternative to fossil fuels. In agriculture, it is increasingly being integrated through several innovative applications that are transforming traditional farming practices. The future of solar energy in agriculture is promising, driven by technological advancements, supportive policies, and increasing awareness of sustainable practices. The objective of the study is to identify the practical applicability of solar pump in other countries and the challenges and opportunities for its applicability in Ethiopia in irrigated agriculture. Existing scholarly research that has been published as journal articles serves as the study's methodology. The resources (Scopus and Google customized search), eligibility and exclusion criteria, review process phases, data abstraction, and analysis are all part of the methods used. The study shows that the solar radiation is the primary source of energy for solar pump and it depends on the climatic condition and geographical location of the area. Most African countries are practicing the solar pump and it was highly practiced in sub-Saharan African countries such as Kenya, Ethiopia, Sudan and also other equatorial and sub-equatorial countries. Additionally, since the North and South hemisphere are linked with permanent cloud cover and only intermittent bright sunshine, the future installation of solar pump will also be practiced in these areas such as the Congo, Gabon, Rwanda, and Senegal. It is also highly practiced in Mali for irrigation, livestock production and for domestic use. There is a growing demand for solar pump irrigation in Ethiopia. Accordingly, one of the government’s strategy is to transit existing motor pump users to solar, while also introducing new solar pump irrigation to those not currently irrigating. The primary challenges of utilizing solar pumps in Ethiopia was high initial costs, while the country's abundant solar radiation and potential for increased agricultural productivity were the best opportunities for its implementation. However, this technology has to be supported through evidence by conducting research and creating awareness for the end users and other policy makers.
Abstract: Electricity is the most cost-effective and efficient energy source for pumping water, but farmers with small, scattered plots might not have access to it. To raise water for irrigation, farmers rely on diesel or gasoline pumps, which is expensive and non-sustainable. For better management of water and economic benefit, considering another option fo...
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Research Article
Single-Volume Magnetic Reconnection Converter (MRC) with Variable β of Plasma Based on Thermodynamic Duty Cycle “α- Dynamo – Magnetic Reconnection”
Oleg Agamalov*
Issue:
Volume 14, Issue 1, February 2025
Pages:
29-49
Received:
4 May 2025
Accepted:
21 May 2025
Published:
23 June 2025
DOI:
10.11648/j.ijepe.20251402.12
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Abstract: The paper considers the justification of a magnetic reconnection converter (MRC) based on a single-volume plasma (spheromak) with a variable β in the turbulent pumping (charging)/discharging phases of the thermodynamic duty cycle “α-dynamo – magnetic reconnection”. To obtain helpful energy, the proposed MRC uses a cyclic combination of two physical processes: 1) α-dynamo, generated by controlled turbulence, increases the global helicity H through the processes of twisting, writhing and bending of magnetic field (MF) flux tubes to the level of a local maximum (optimally global), which is determined by the plasma parameters, boundary conditions, tension of magnetic field lines, etc., and corresponding the MF strength and stochasticity in a limited plasma volume. At this stage of MF turbulent pumping, which corresponds to the α-dynamo physical process, β of the plasma will decrease to the minimum possible value with a corresponding increase in the accumulated "topological" energy of the MF; 2) when reaching the local (if possible global) maximum of the MF strength and stochasticity, turbulent magnetic reconnection (TMR) occurs in many places of the plasma, which lowers the state of the local (if possible global) maximum of the MF strength and stochasticity and increases the kinetic stochasticity of the plasma particles, accelerating and heating them, which is used in direct energy converters (DECs), and receiving coils of electrical energy. At this stage of turbulent discharge, which corresponds to multiple TMR, β of the plasma will increase to the maximum possible value with a corresponding increase in its kinetic and thermal energy. When the kinetic stochasticity of plasma particles decreases and reaches a minimum, the control system repeats the MF's turbulent pumping, generating multiple α-dynamo processes in the plasma, and the cycle repeats.
Abstract: The paper considers the justification of a magnetic reconnection converter (MRC) based on a single-volume plasma (spheromak) with a variable β in the turbulent pumping (charging)/discharging phases of the thermodynamic duty cycle “α-dynamo – magnetic reconnection”. To obtain helpful energy, the proposed MRC uses a cyclic combination of two physical...
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