Renewable Energy Alternatives

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2013 ISES Solar World Congress Promotion of PV Uptake and Sector Growth in Kenya through Value Added Training in PV Sizing, Installation and Maintenance
(Science Direct, 2014) Justus Simiyu; Sebastian M. Waita; Alex Ogacho; Robinson Musembi
Sub-Saharan Africa, and more specifically the East African region, has the lowest rates of access to electricity in the world. On average, at most 15% of the rural population has access to electricity. Rural households and remote institutions use traditional energy sources such as charcoal, firewood, kerosene and diesel for generator sets, batteries and dry cell batteries. On the other hand, the region is one of the most promising in the world in economic development with growth levels being high and market saturation is a far away future problem. This growth has however been hampered by several factors with lack of energy being one of them. Kenya being one of the countries in the region faces a similar problem with the traditional sources of hydro facing weather related challenges. The situation is more wanting in the rural setting having only achieved electrification rates of between 5 and 10%. The rural being where the majority of low-income earning groups reside is further compounded with large geographical imbalance in electricity demand and supply. The main challenge to adopting pv utilization however, is lack of local capacity to handle the uptake all the way from solar home systems to grid connected and hybrid systems. According to Kenya Renewable Energy Association (KEREA), it is estimated that between 800 and 1000 pv technicians have been in practice since this sector started in Kenya in the late eighties, majority of them having the basic skills but no formal training to provide the service. They however have been offering necessary service to end-users and are hence an important aspect in the pv sector as a whole. Currently the pv (mainly SHS) comprise an over the counter trade system which provides loopholes when it comes to quality of products and installation. To safeguard the quality and safety of installations, formal training has to be incorporated in the system.
A Review of the Current Trends in the Production and Consumption of Bioenergy
(Sami Publishing Company, 2021-02-01) Korir, Benjamin K.; Kibet, Joshua; Mosonik, Bornes C.
With the current traditional fossil fuels depleting at an alarming rate coupled with environmental degradation because of toxic emissions, there is a mounting desire in search of renewable and sustainable energy resources. In this regard, bioenergy is considered one of the greatest potential to address the global energy demands in order to foster confidence in energy security, economic sustainability, and environmental protection. Global use of biomass to generate electricity and enhanced green energy transport is expected to increase in the near future. Accordingly, the demand for renewable energy is aimed at minimizing energy poverty and mitigation against climate change. Bioenergy despite bioconversion challenges is one of the key solutions to the world’s current energy demands. Model bioenergy plant sources – Croton megalocarpus, palm oil, Jatropha, and soybeans are briefly discussed in this review as major sources of bioenergy. The increased focus on bioenergy has been necessitated by high oil and gas prices, and the desire for sustainable energy resources. Nonetheless, corrupt practices and lack of political goodwill has hampered efforts towards achieving the full utilization of bioenergy. Corruption has been widely cited as a major setback to bioenergy development in a range of global jurisdictions. In order to minimize environmental damage, carbon trade has been projected as a necessary action by developing countries to reduce carbon emissions. Generally, the analysis of the use of fossil fuels across the world shows a strong interrelationship involving energy utilization, degradation of air quality, and environmental health concerns.
A Simple Low Cost Solar Panel/cell Characterization Experiment for Senior Undergraduate Students
(ISES, 2015-11-11) Sebastian Waita*, Justus Simiyu, Alexander N. Kiragu, Vivian Imali and Bernard Aduda
A simple low cost solar cell characterization experiment has been developed for senior undergraduate students in the Department of Physics, University of Nairobi. Experiments were conducted with solar panels (also called solar modules/photovoltaic modules) rated 20 W and 40 W peak power on different sunny days on the roof top of Physics Department, University of Nairobi. It was observed that the current- voltage (I-V) curves obtained for all the measurements for each panel were comparable. The fill factor (FF), short circuit current (Isc), open circuit voltage (Voc), current at maximum power point (Im) and voltage at maximum power point (Vm) were within acceptable margins when compared with the manufacturer’s rated values, an indication of the reliability and accuracy of the method. The method eliminates the need for expensive characterization equipment like solar simulators, unaffordable by many developing country institutions. The experiment is recommended for senior undergraduate students with an interest in renewable energy as one way of introducing them to renewable energy. The experiment may also help in arousing the learner’s interest in solar energy.
Adoption of Improved Cookstoves in the Peri-urban Areas of Nairobi: Case of Magina Area, Kiambu County, Kenya
(Research Gate, 2019-02-04) Kong'ani, Lilian Sarah; Ang'u, Cohen; Muthama, Nzioka
Concerted efforts have been made to enable communication and adoption of improved cookstoves by diverse development organizations in Kenya. However, their adoption remains low. This study sought to examine levels of adoption and use of improved cookstoves in Magina, Kiambu County and determine factors affecting their adoption and use. Results demonstrate that 93% of the households received the cookstoves from developmental programmes, among these 50% were making use of them but only 14% of the 50% had fully adopted them as main cookstoves. Efficiency and suitability, socio-cultural practices, economic capacity, limited capacity to appreciate the improved cookstoves concept and governance considerations were the cited limiting factors to adoption and use. There is need for an enabling policy and strategies to implement the bottom-up approach in the design and implementation of improved cookstoves to facilitate the upscaling of the adoption and use of improved cookstoves to conserve the forests in the country for sustainable development.
ASSESSMENT OF WIND CHARACTERISTICS AND POWER POTENTIAL AT KESSES LOCATION - UASIN-GISHU COUNTY, KENYA
(University of Eldoret, 2015) Cheruiyot, Wilkins
Wind energy is increasingly becoming popular all over the world as a green energy source for electricity generation since it is renewable and environmentally friendly. Pioneer wind turbines for electricity generation in Kenya were recently installed at Ngong Hills and Lake Turkana, and more is expected to be initiated in different parts of the country. Wind turbines extract the kinetic energy carried by the flowing wind and this energy is directly proportional to the cube of wind speed. Thus, the wind speed is the most important parameter to consider in designing and selecting an efficient wind energy conversion system. Meteorological Department (MET) and some learning institutions in Kenya have been collecting and storing climatic data for several years, including wind speeds and most of them have not been analyzed. Precise knowledge of availability of wind at any given location is a pre-requisite for the effective planning and implementation and speed analysis is useful for the assessment of wind characteristicsand power potential at a location. In this work, analyses of five years (2009-2013) wind speed data collected at a meteorological unit at Moi University, Kesses area, Uasin Gishu County- Kenya, was done. The station measures wind speed at a height of 2 m and were extrapolated to the standard height of measurements of 10 m and typical hub heights of 40 m, 70 m and 100 m for purposes of characterization and determination of energy potential respectively. The extrapolated results revealed that the average annual wind speed at the height of 10 m is 3.86 ms-1, meaning that the location wind speed can be classified as class IV with a maximum wind power density of 100 Wm-2. The average annual wind speed at the hub heights of 40 m, 70 m and 100 m were 5.48ms-1, 6.33ms-1and 6.93ms-1, giving corresponding power densities of 115.563Wm-2, 175.395Wm-2and 228.917 Wm-2respectively. Weibull distribution model was used in the analysis of wind speed distribution. The Weibull scale parameter range from 2.543 ms-1to a maximum of 3.046 ms-1. The Weibull shape parameter was peaked at 5.902 in the year 2012. Both cumulative and probability density function were assessed and graphically presented.Results showed that the site has potential for harnessing wind energy for electricity generation and both small and medium scale wind power turbines are recommended for installation at the site.
Bio-alkanol gel fuel for rural households in the Lake Victoria Basin
(2019) Nyambega, Benson
The clean energy potential in eastern Africa is sufficient to develop a strong economic, social and environmentally beneficial supply that can exceed regional energy needs, make significant progress in increasing energy access, and do so in a way that achieves environmental sustainability and a more diverse and vibrant private sector.The Lake Victoria basin which is a significant water resource for the region is characterized by high rates of deforestation. Only 6% of rural households around the lake basin rely on modern fuels with the majority predominantly using solid fuel such as charcoal and firewood for their primary cooking needs. The resulting degradation of the catchment areas of Lake Victoria basin is a major threat to these resources and livelihoods. Moreover, firewood and paraffin which are popularly used by the rural households are a major source of indoor air pollution and are known to cause numerous respiratory ailments such as pneumonia, asthma and lung cancer among others.To minimize reliance on wood-based fuel and paraffin, the project will commercialize a renewable biofuel known as ‘bio-alkanol gel’ made from fruit waste. The bio-alkanol gel also has the potential to repel mosquitoes that cause malaria. An enterprise will be established through which the gel will be commercially produced, and sustainable business models developed to scale the product to benefit rural household communities in the Lake Victoria basin, youth and women among others
Biogas Technology in Kenya
(KIRDI, 2021-06-15) Lumadede H.M.*, Wangai L., Kwach S., Khalifa J. and Mbithi V.
Research into biogas production and sustainability in Kenya is in progress at Kenya Industrial Research and Development Institute (KIRDI) through its biogas laboratory. Biogas production is one of the renewable energies which we use in Kenya. Biogas importance, development, opportunities and the economical and sustainability in Kenya are discussed. The full exploitation of Kenya ‘s agricultural potential will yield a lot of biomass through which innovative use of the available bio waste from maize, cotton, tea and sugarcane can be utilized. Present and emerging biogas technologies convert these biowaste into renewable energy, thereby replacing the expensive fossil energy sources, and reducing dependency on fossil fuels. Other substrates like water hyacinth and molasses distillery waste have been found to be a good source of biogas. This review examines the energy potential of biogas production from crop residues. The findings will promote biogas addition to the energy mix Kenya needs as well as providing approaches, achievements, lessons learnt and other relevant aspects of domestic biogas programmers. It aims to achieve a greater, more effective use of biogas and contributes to the process by providing knowledge of biogas use in Kenya and its potential. Development partners are supporting the implementation of market-based domestic biogas programmers in Kenya with a view to establish a commercially viable biogas sector.
Characteristics of TiO2 Compact Layer prepared for DSSC application
(Path of Science, 2018-11-04) Musila, Nicholas; Munji, Mathew; Simiyu, Justus; Masika, Eric; Nyenge, Raphael; Kineene, Miriam; Musila, Nicholas; Munji, Mathew; Simiyu, Justus; Masika, Eric; Nyenge, Raphael; Kineene, Miriam
Dye-sensitized solar cells (DSSCs) offer an economically reliable and suitable alternative in moderating the challenges presented by the existing convectional photovoltaic cells. However, the efficiency of dye-sensitized solar cells has remained relatively low. For this reason, this research was aimed at studying the characteristics of TiO2 compact layer that can be applied in DSSCs as a way of improving efficiency. To achieve this, TiO2 compact layer was deposited on a conductive glass substrate by using Holmarc’s Spray Pyrolysis system, using Ultrasonic Spray Head and spraying in the vertical geometry. X-ray Diffraction studies revealed that TiO2 compact layer was of anatase phase and had tetragonal crystalline structure. Raman spectroscopy showed that the most intense peak appeared at 142 cm-1 due to the external vibration of the anatase structure. Hall Effect studies revealed that TiO2 compact layer has a high density of charge carriers’ value of 1.25 × 1019 cm-3 hence it can be used in DSSC applications.
Characterization of Local Nano-Heat Transfer Fluids for Solar Thermal Collection
(Advances in Materials Science and Engineering, 2020-07-07) Millien, Kawira
Performance of organic oils in solar thermal collection is limited due to their low thermal conductivity when they are compared to molten salt solutions. Extraction of organic oils from plants can be locally achieved. The purpose of this study was to investigate the effect of use of copper nanoparticles in some base local heat transfer fluids (HTFs). Addition of volume fraction of 1.2% of the copper nanoparticles to oil-based heat transfer fluids improved their thermal conductivity as deduced from the thermal heat they conducted from solar radiation. The oil-based copper nanofluids were obtained by preparation of a colloidal solution of the nanoparticles. Impurities were added to increase the boiling point of the nano-heat transfer fluids. Stabilizers were used to keep the particles suspended in the oil-based fluids. The power output of the oil-based copper nano-heat transfer fluids was in the range of 475.4 W to 1130 W. The heat capacity of the steam in the heat exchanger was 93.7% dry and had a thermal capacity of 5.71 × 103 kJ. The heat rate of flow of the oil-based copper nano-heat transfer fluids was an average of 72.7 Js−1·kg−1 to 89.1 Js−1·kg−1. The thermal efficiency for the oil-based copper nano-heat transfer fluids ranged from 0.85 to 0.91. The average solar thermal solar intensity was in the range 700 Wm−2 to 1180 Wm−2. The heat exchanger used in this study was operating at 4.15 × 103 kJ and a temperature of 500.0°C. The heat transfer fluids entered the exchanger at an average temperature of 381°C and exited at 96.3°C and their heat coefficient ranged between 290.1 Wm−2°C and 254.1 Wm−2°C. The average temperatures of operation ranged between 394.1°C and 219.7°C with respective temperature efficiencies ranging between 93.4% and 64.4%. It was established that utilization of copper nanoparticles to enhance heat transfer in oil-based local heat transfer fluids can mitigate energy demand for meeting the world’s increasing energy uses, especially for areas inaccessible due to poor land terrain.
Characterization of Local Nano-Heat Transfer Fluids for Solar Thermal Collection
(Hindawi, 2020) Millien, Kawira
Performance of organic oils in solar thermal collection is limited due to their low thermal conductivity when they are compared to molten salt solutions. Extraction of organic oils from plants can be locally achieved. The purpose of this study was to investigate the effect of use of copper nanoparticles in some base local heat transfer fluids (HTFs). Addition of volume fraction of 1.2% of the copper nanoparticles to oil-based heat transfer fluids improved their thermal conductivity as deduced from the thermal heat they conducted from solar radiation. The oil-based copper nanofluids were obtained by preparation of a colloidal solution of the nanoparticles. Impurities were added to increase the boiling point of the nano-heat transfer fluids. Stabilizers were used to keep the particles suspended in the oil-based fluids. The power output of the oil-based copper nano-heat transfer fluids was in the range of 475.4 W to 1130 W. The heat capacity of the steam in the heat exchanger was 93.7% dry and had a thermal capacity of 5.71 × 103 kJ. The heat rate of flow of the oil-based copper nano-heat transfer fluids was an average of 72.7 Js−1·kg−1 to 89.1 Js−1·kg−1. The thermal efficiency for the oil-based copper nano-heat transfer fluids ranged from 0.85 to 0.91. The average solar thermal solar intensity was in the range 700 Wm−2 to 1180 Wm−2. The heat exchanger used in this study was operating at 4.15 × 103 kJ and a temperature of 500.0°C. The heat transfer fluids entered the exchanger at an average temperature of 381°C and exited at 96.3°C and their heat coefficient ranged between 290.1 Wm−2°C and 254.1 Wm−2°C. The average temperatures of operation ranged between 394.1°C and 219.7°C with respective temperature efficiencies ranging between 93.4% and 64.4%. It was established that utilization of copper nanoparticles to enhance heat transfer in oil-based local heat transfer fluids can mitigate energy demand for meeting the world’s increasing energy uses, especially for areas inaccessible due to poor land terrain.
Compositional analysis and optical properties of Co doped TiO2 thin films fabricated by spray pyrolysis method for dielectric and p hotocatalytic applications
(Science Direct, 2017-01-01) Wafula, Henry Barasa; Musembi, Robinson Juma; Juma, Albert Owino; Tonui, Patrick; Simiyu, Justus; Sakwa, Thomas; Prakash, Deo; Verma, K. D.
Cobalt doped TiO2 thin films (CTF) deposited by spray pyrolysis has been studied. The compositional analysis has been done using RBS method, while optical spectroscopy has been done by measuring the transmittance and reflectance of the films. The CTF thin films were prepared by doping TiO2 at different concentration levels of Co which was varied between 0 and 4.51 at.%. The optical transmittance of the thin film has been found to be about 80% in the visible and near infra red regions. The calculated optical band gap has been observed to shift by about 0.22 eV, this shows a high potential for application as a dielectric and a Photocatalyst material.
Creating livelihoods through clean energy and agriculture
(The International Journal Of Rural development, 2020-06-26) Shirley, Rebekah
Just 35 per cent of the African population have access to electricity, with rural access rates at less than one-third of urban communities. Not only could decentralised renewable energy technologies help in meeting energy demand in rural areas in a climate-friendly manner, and promoting innovations in the agri-food sector, they are also an important potential driver of local job creation and the formalisation of labour – provided that the skills gaps hindering the sector’s growth can be closed.
Dioxin and dibenzofuran like molecular analogues from the pyrolysis of biomass materials—the emerging challenge in bio-oil production
(BMC Chemistry, 2021-01-15) Kirkok, Samuel K.; Kibet, Joshua K.; Kinyanjui, Thomas; Okanga, Francis I.; Nyamori, Vincent O.
Introduction The aggressive search for renewable energy resources and essential pyrosynthetic compounds has marked an exponential rise in the thermal degradation of biomass materials. Consequently, clean and sustainable transport fuels are increasingly desirable in a highly industrialized economy, for energy security and environmental protection. For this reason, biomass materials have been identified as promising alternatives to fossil fuels despite the challenges resulting from the possible formation of toxic nitrogen-based molecules during biomass degradation. In order to understand the free radical characteristic challenges facing the use of bio-oil, a brief review of the effects of free radicals in bio-oil is presented. Methodology Pyrolysis was conducted in a tubular flow quartz reactor at a residence time of 2 s at 1 atm. pressure, for a total pyrolysis time of 5 min. The thermal degradation of biomass components was investigated over the temperature range of 200 to 700 °C typically in 50 °C increments under two reaction conditions; pyrolysis in N2 and oxidative pyrolysis in 5% O2 in N2. The pyrolysate effluent was analysed using a Gas chromatograph hyphenated to a mass selective detector (MSD). Results The yield of levoglucosan in the pyrolysis of cellulose in the entire pyrolysis temperature range was 68.2 wt % under inert conditions and 28.8 wt % under oxidative conditions. On the other hand, formaldehyde from pyrolysis of cellulose yielded 4 wt % while that from oxidative pyrolysis was 7 wt % translating to ⁓ 1.8 times higher than the yield from pyrolysis. Accordingly, we present for the first time dioxin-like and dibenzofuran-like nitrogenated analogues from an equimassic pyrolysis of cellulose and tyrosine. Levoglucosan and formaldehyde were completely inhibited during the equimassic pyrolysis of cellulose and tyrosine. Conclusion Clearly, any small amounts of N-biomass components such as amino acids in cellulosic biomass materials can inhibit the formation of levoglucosan–a major constituent of bio-oil. Overall, a judicious balance between the production of bio-oil and side products resulting from amino acids present in plant matter should be taken into account to minimize economic losses and mitigate against negative public health concerns.
Effect of Stirring Intervals on Biogas Production from Cow Dung and Maize Silage Mix Ratio
(International Journal of Power and Energy Research, 2021-04-30) Chol, Monyluak M. Y.; Muchuka, Nicasio M.; Nyaanga, D.
Most biogas plants’ poor performance may be attributed to inadequate stirring strategy. The study evaluated the effect of stirring intervals on biogas production from cow dung and maize silage mixture (at mixed ratio 3:1) digested in a 0.15m3 laboratory digester at 30℃. SIEMENS LOGO PLC and ATV12HU15M2 Drive automatically controlled the stirring of 100 rpm for 3minutes at intervals of 1hour, 2hours, 6hours and 12hours with no stirring as control. The stirring intervals showed a significant effect on biogas production (P≤0.05) with 6hours and 12hours increased biogas by 3.11% and 1.48%, and the methane increase of 8.77% and 1.75%, respectively. The 2hours and 1hour reduced biogas by 26.5% and 39.35%, and methane decreased by 3.52% and 15.79%, respectively compared to control (implying that the frequent stirring is not good for biogas). The stirring interval of 6hours is thus recommended for 0.15m3 laboratory batch reactor of cow dung and maize silage.
Effect of TiO2 Compact Layer on DSSC Performance
(Social Science Research Network, 2018-09-30) Musila, Nicholas; Munji, Mathew; Simiyu, Justus; Masika, Eric; Nyenge, Raphael
Dye-sensitized solar cells offer an economically reliable and suitable alternative in moderating the challenges presented by the existing convectional photovoltaic cells. Whereas, for convectional solar cells the semiconductor adopts both the duty of light absorption and charge carrier transport, these two functions are separated in dye-sensitized solar cells. However, the efficiency of dye-sensitized solar cells has remained relatively low. For this reason, this research was aimed at how to increase the dye-sensitized solar cells performance. To achieve this, compact cover of TiO2 was deposited on a conductive glass substrate by using Holmarc’s Spray Pyrolysis system, using Ultrasonic Spray Head and spraying in vertical geometry, while TiO2 nanoparticles and nanotubes were deposited by screen printing technique on top of a transparent conducting FTO glass slide with or without the TiO2 compact layer. Transmission characteristics showed that introducing TiO2 compact layer on the conductive film lowers the transmission while reflectance properties were less than 15 % for all the prepared thin films. SEM micrographs showed that TiO2 nanotubes had a skein-like morphology with abundant number of nanotubes intertwined together to form a large surface area film. Solar cell performance properties revealed that introducing compact layer to dye-sensitized solar cells improved the performance by 145 % (from 1.31 % to 3.21 %) while TiCl4 treatment on compact layered dye-sensitized solar cells increased the efficiency by 28.79 % (from 0.66 % to 0.85 %).
Effect of Total Solids on Biogas Production in a Fixed Dome Laboratory Digester under Mesophilic Temperature
(Annals of Advanced Agricultural Sciences, 2020-05) Barasa, Henry; Nyaanga, David; Njue, Musa; Matofari, Joseph
An investigation on the effect of total solids on biogas production was done using a laboratory scale batch reactor of 0.15 m3 capacity. The feedstock was dung from dairy cows managed under a free-range system. Experiments were done on a substrate having total solids of 6%, 7%, 8%, 9%, and 10% at a constant temperature of 35°C; and the mean biogas production was 0.249, 0.304, 0.487, 0.287, and 0.244 m3 of biogas per m3 of digester volume per day (m3/m3d), respectively. It was concluded that the highest average biogas production of 0.487 m3/m3d is attained at total solids of 8%.
Effects of Green Bio-Catalysts and Ferric Oxide in Cryo-Mesophillic Temperature Biogas Production
(International Journal of Research and Innovation in Applied Science (IJRIAS), 2019-09) Chaka, Osano Aloys and Bakari
Biogas production at low temperature regimes isannoyingly slow and yields low biogas volumes. Most biogassupplements are expensive and substrate-specific. The effects oftwo bio-catalysts Saccharomyeces spp. and Acanthaceae spp. andan inorganic catalyst ferric oxide on biogas production using cowdung slurry was investigated. 1.5L batch anaerobic digesteroperating in unstirred cryo-mesophilic temperature regime of20.0 -24.5 0C were utilized. The substrate underwent mildsynergistic pre-treatment by steaming with 1% sodiumhydroxide solution. The alkalinity and volatile acids of thesubstrates were insignificantly perturbed by inclusion of theadditives. Additives Saccharomyeces spp. and Acanthaceae spp.stabilized digestion temperature while ferric oxide stabilized pHdrifts. The overall biogas yields produced in the 100-dayretention period were in the order of 4615ml (990.34ml/g-Volatilesolids) for ferric oxide, 2335ml (494.08ml/g-Volatile solids) forSaccharomyeces spp., 1750ml (328.94ml/g-Volatile solids) forAcanthaceae spp. and 1030ml (212.37ml/g-Volatile solids) for thecontrol sample. Use of these additives would thus optimize biogasproduction in cold countries.
Effects of TiO2 Blocking Layer on Photovoltaic Characteristics of TiO2/Nb2O5 Dye Sensitized Solar Cells
(Springer Nature, 2020-09-13) Owino, Brian O.; Nyongesa, Francis W.; Ogacho, Alex A.; Aduda, Bernard O.; Odari, Benjamin V.
This study reports on the effect of introducing TiO2 compact layer on the photovoltaic characteristics of TiO2/Nb2O5 composite dye sensitized solar cell. The compact layer was deposited by spray pyrolysis technique. It was observed that introduction of 60 nm thick compact layer improved the short circuit current density Jsc,Open circuit voltage Voc, and efficiency of the cell from 4.9 mA/cm2 to 8.2 mA/cm2, 6.8×10-1 V to 7.2×10-1 V and 1.9 % to 3.4 % respectively compared to traditional cell prepared without compact layer. Electrochemical impedance spectroscopy confirmed an increase in recombination resistance from 5.5×101 Ω.cm2 for bare DSSC to 9.0×101 Ω.cm2 for DSSC with compact layer thereby improving electron lifetime of the cells from 2.5×10-4 s to 386.9×10-4 s.
Electron Impact Elastic Scattering of Strontium Using Distorted Wave Method
(Kenyatta University, 2018-11)
Differential and integral cross sections for electron-atom are useful for interpretation and understanding of electron contact with the targets and for determining dynamics of the collision processes. They are useful in X-ray photoelectron spectroscopy (XPS), upper atmosphere dynamics, Monte-Carlo simulation (MCS), Auger-electron spectroscopy (AES), in gaseous-exchange, laser development, plasma physics and fluorescent lighting. For elastic scattering of strontium very few calculations have been performed and currently there are no known results using the present method. Also the available theoretical results do not have other results to be compared with so it makes it important to obtain results to compare them and to be compared with future experimental results. In calculation of differential and integral cross section for elastic scattering of electron by strontium atom, first-order distorted wave born approximation method has been used to determine DCS and ICS at impact energies of 10eV to 200eV and scattering angles ranging from 00 to 1800. Also in this study at the initial state, both initial and final channel distortion potential of elastic scattering of electron by a strontium atom are taken as the static potentials since it is an elastic scattering. The distorted waves are expanded in terms of radial wavefunctions and spherical harmonics, Numerov method was then used to solve the radial equations to obtain the radial wavefunctions. The Madison and Bartschat computer program DWBA1 for e- - H scattering was modified to perform the mathematical computations for e - - Sr scattering and the results for differential and integral cross sections are calculated and compared with the available results. The integral cross sections (ICS) results agree well qualitatively with the other theoretical results. At lower incident energies (10-30 eV), the present differential cross section (DCS) results disagree with results obtained from optical potential method. This is because the first order distorted wave method gives poor results at low impact energies and also the nature of the distortion potential used. At intermediate and higher energies (60-200 eV), the present DCS results agree well with the results obtained from optical potential method. In conclusion, the DWBA was developed and applied to 𝑒− - Sr scattering, changes on the DWBA1 computer program were made for strontium, differential cross section (DCS) and integral cross section (ICS) at impact energies 10-200eV for elastic scattering of electron-strontium were determined using DWBA at intermediate and high energies and the results compared with the other available results. From this work it was recommended that some experimental studies on electron impact elastic scattering of strontium should be made to give results for comparison with the calculated results, more theoretical studies using other methods should be conducted on DCS and ICS for purposes of comparison with the present results, a distortion potential that incorporates the polarization potential, exchange potential and absorption potential should be used in the calculation and the present method incorporating all the distortion potentials should be extended further for electron impact elastic scattering of other alkaline earth metals such as beryllium, cesium, ytterbium, and radium.
EMERGING TRENDS FOR ENERGY CONSUMPTION WITHIN ICT DEVICES
(International Journal of Engineering Applied Sciences and Technology, 2020) Chitechi, Kadima Victor; Odoyo, Collins Otieno
The information and communicationtechnology (ICT) is closely related to the future ofglobal energy consumption, not only because theICT equipment itself increasingly consumesenergy, but also because it is a general-purposetechnology, which may affect energy use of almostall sectors. The growing demand for ICT devicesand services outpaces the efficiency gains ofindividual devices. Previous studies had alludedthat cumulated potentials for ICT-induced savingsis several times larger than the entire energyconsumption of ICT itself. More studies on ICTrelated energy consumption do exist, and anincreasing number of studies looking at ICTinduced energy efficiency. The few studies,however, considering both aspects, typically do soindependently, without relating the two aspects.Moreover, in the energy efficiency discourse, ICTis usually treated as a monolithic block oftechnologies – only the application areas that areexpected to benefit from it being differentiated. Itis only by consequently following low energyconsumption targets for technologies with a lowenergy efficiency potential, while at the same timenot suffocating technologies with a high-energyefficiency potential through restrictiveconsumption targets, this paper will discuss thevarious emerging trends in energy consumptionswithin ICT devices.

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