Modelling and analysis of a PV/wind/diesel hybrid standalone microgrid for rural electrification in Nigeria

The scarce electricity supply in Nigeria is a key factor to the low industrial development in a country well-known for having the least electrification in Africa per capita. Presently, Nigeria employs four different kinds of energy such as coal, natural gas, hydro, and oil. Three of the four resources mentioned above used for the production of energy in Nigeria is connected with increasing emissions of greenhouse gas: natural gas, oil, and coal, with coal releasing the worst. This paper presents a model and analysis of PV/Wind/Diesel hybrid system for rural electrification in Kaduna state, northern Nigeria. HOMER (Hybrid Optimization Model for Electric Renewable) software tool was used for optimization and modeling of this work. Simulation results show that the PV/Wind/Diesel system with Battery storage is the most cost-effective system since it recorded considerable cost of energy and reduces CO2 emissions significantly.

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Comparison between Concentrated Solar Power and Gas-Based Generation in Terms of Economic and Flexibility-Related Aspects in Chile

Energies ◽

10.3390/en14041063 ◽

2021 ◽

Vol 14 (4) ◽

pp. 1063

Author(s):

Catalina Hernández Moris ◽

Maria Teresa Cerda Guevara ◽

Alois Salmon ◽

Alvaro Lorca

Keyword(s):

Natural Gas ◽

Solar Power ◽

Renewable Energy Sources ◽

Cost Effective ◽

Hybrid Plant ◽

Point Of View ◽

Concentrated Solar Power ◽

Economic Point ◽

Hybrid Plants ◽

Cost Of Energy

The energy sector in Chile demands a significant increase in renewable energy sources in the near future, and concentrated solar power (CSP) technologies are becoming increasingly competitive as compared to natural gas plants. Motivated by this, this paper presents a comparison between solar technologies such as hybrid plants and natural gas-based thermal technologies, as both technologies share several characteristics that are comparable and beneficial for the power grid. This comparison is made from an economic point of view using the Levelized Cost of Energy (LCOE) metric and in terms of the systemic benefits related to flexibility, which is very much required due to the current decarbonization scenario of Chile’s energy matrix. The results show that the LCOE of the four hybrid plant models studied is lower than the LCOE of the gas plant. A solar hybrid plant configuration composed of a photovoltaic and solar tower plant (STP) with 13 h of storage and without generation restrictions has an LCOE 53 USD/MWh, while the natural gas technology evaluated with an 85% plant factor and a variable fuel cost of 2.0 USD/MMBtu has an LCOE of 86 USD/MWh. Thus, solar hybrid plants under a particular set of conditions are shown to be more cost-effective than their closest competitor for the Chilean grid while still providing significant dispatchability and flexibility.

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Cogeneration Economics for Greenhouses in Europe

Energies ◽

10.3390/en13133373 ◽

2020 ◽

Vol 13 (13) ◽

pp. 3373 ◽

Cited By ~ 2

Author(s):

Kalliopi Tataraki ◽

Eugenia Giannini ◽

Konstantinos Kavvadias ◽

Zacharias Maroulis

Keyword(s):

Natural Gas ◽

Combustion Engine ◽

Meteorological Data ◽

Cost Effective ◽

Comparative Investigation ◽

European Countries ◽

Price Ratio ◽

Efficient System ◽

Heating And Cooling ◽

Cost Of Energy

Cogeneration is a cost-effective technology, and modern greenhouses are considered one of the best applications for it due to their energy intensity. Taking into account that in such cases the production cost is significantly affected by the cost of energy, the potential of combined heat and power (CHP) has already been examined and proved in practice in some European countries, with the Netherlands being the most representative example. In this study, a comparative investigation of the greenhouse energy cost in all European countries is presented through the use of a combined cooling heat and power (CCHP) system. Using actual historical data spanning a decade, a total overview of the European level is given regarding greenhouse thermal requirements and CCHP energy costs for the cultivation of products with an accepted temperature cultivation range 20 ± 5 °C. By consulting (a) the available daily historical meteorological data for the 2008–2018 period, (b) the recorded actual electricity and natural gas prices for the 2008–2018 period, and (c) the technical characteristics of the CCHP system, the annual heating and cooling requirements of greenhouses are determined for all EU countries. Assuming a cogeneration unit with an internal combustion engine (ICE) as a prime mover, as well as a single-effect absorption chiller for the production of useful cooling, the unitary cost of energy is estimated along with the annual cost for heating and cooling per unit cultivation area. Using this methodology, the economic efficiency of cogeneration in greenhouses is assessed for the selected 10-year period, allowing the identification of the countries that benefit the most from this technology. The results indicate that the spark ratio (e.g., the electricity to natural gas price ratio) is the most crucial parameter for greenhouse costs. For countries where the ratio is larger than 3, greenhouses can even result in an extra cashflow instead of energy expenditures. The most favorable conditions for cogeneration use were found in Italy and the United Kingdom with an average spark ratio more than 4, resulting in an annual total cost of heating energy close to −7 €/m2 per year. On the other hand, cogeneration proved not to be a cost-efficient system in Sweden and Finland as a result of significantly high greenhouse energy requirements.

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Extended Routine Follow-up of Primary Uncomplicated Hip and Knee Arthroplasty is not Necessary

The Open Orthopaedics Journal ◽

10.2174/1874325001913010266 ◽

2019 ◽

Vol 13 (1) ◽

pp. 266-271

Author(s):

Georgina Kakra Wartemberg ◽

Thomas Goff ◽

Simon Jones ◽

James Newman

Keyword(s):

Aseptic Loosening ◽

Revision Surgery ◽

Revision Arthroplasty ◽

Cost Effective ◽

Face To Face ◽

Primary Surgery ◽

Effective System ◽

Knee Revision Surgery ◽

Knee Revision

Aims: To create a more effective system to identify patients in need of revision surgery. Background: There are over 160,000 total hip and knee replacements performed per year in England and Wales. Currently, most trusts review patients for up to 10 years or more. When we consider the cost of prolonged reviews, we cannot justify the expenditure within a limited budget. Study Design & Methods: We reviewed all patients' notes that underwent primary hip and knee revision surgery at our institution, noting age, gender, symptoms at presentation, referral source, details of the surgery, reason for revision and follow up history from primary surgery. Results: There were 145 revision arthroplasties (60 THR and 85 TKR) that met our inclusion criteria. Within the hip arthroplasty group, indications for revision included aseptic loosening (37), dislocation (10), and infection (3), periprosthetic fracture, acetabular liner wear and implant failure. All thirty-seven patients with aseptic loosening presented with pain. Twenty-five were referred from general practice with new symptoms. The remaining were clinic follow-ups. The most common reason for knee revision was aseptic loosening (37), followed by infection (21) and then progressive osteoarthritis (8). Most were referred from GP as a new referral or were clinic follow-ups. All patients were symptomatic. Conclusion: All the patients that underwent revision arthroplasty were symptomatic. Rather than yearly follow up, we recommend a cost-effective system. We are implementing a 'non face-to-face' system. Patients would be directly sent a questionnaire and x-ray form. The radiographs and forms will be reviewed by an experienced arthroplasty surgeon. The concerning cases will be seen urgently in a face-to-face clinic.

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Pitfalls in the Immunochemical Determination of β‑Lactam Antibiotics in Water

Antibiotics ◽

10.3390/antibiotics10030298 ◽

2021 ◽

Vol 10 (3) ◽

pp. 298

Author(s):

Alexander Ecke ◽

Rudolf J. Schneider

Keyword(s):

Limit Of Detection ◽

Cost Effective ◽

Enzyme Linked Immunosorbent Assay ◽

Degree Of Hydrolysis ◽

Site Analysis ◽

Antibody Recognition ◽

Immunochemical Determination ◽

Key Factor ◽

Lactam Ring

Contamination of waters with pharmaceuticals is an alarming problem as it may support the evolution of antimicrobial resistance. Therefore, fast and cost-effective analytical methods for potential on-site analysis are desired in order to control the water quality and assure the safety of its use as a source of drinking water. Antibody-based methods, such as the enzyme-linked immunosorbent assay (ELISA), can be helpful in this regard but can also have certain pitfalls in store, depending on the analyte. As shown here for the class of β-lactam antibiotics, hydrolysis of the β‑lactam ring is a key factor in the immunochemical analysis as it influences antibody recognition. With the antibody used in this study, the limit of detection (LOD) in the immunoassay could be significantly reduced by hydrolysis for the five tested penicillins, with the lowest LOD for carbenicillin (0.2 nmol/L) and the greatest impact on penicillins G and V (reduction by 85%). In addition to enhanced quantification, our strategy also provides access to information about the degree of hydrolysis in water samples as shown for the most abundant penicillin amoxicillin.

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Practical Cross-Layer Radio Frequency-Based Authentication Scheme for Internet of Things

Sensors ◽

10.3390/s21124034 ◽

2021 ◽

Vol 21 (12) ◽

pp. 4034

Author(s):

Arie Haenel ◽

Yoram Haddad ◽

Maryline Laurent ◽

Zonghua Zhang

Keyword(s):

Internet Of Things ◽

Radio Frequency ◽

Real Life ◽

Computation Time ◽

Cost Effective ◽

Battery Life ◽

Cross Layer ◽

Security Level ◽

Cost Of Energy ◽

Iot Devices

The Internet of Things world is in need of practical solutions for its security. Existing security mechanisms for IoT are mostly not implemented due to complexity, budget, and energy-saving issues. This is especially true for IoT devices that are battery powered, and they should be cost effective to be deployed extensively in the field. In this work, we propose a new cross-layer approach combining existing authentication protocols and existing Physical Layer Radio Frequency Fingerprinting technologies to provide hybrid authentication mechanisms that are practically proved efficient in the field. Even though several Radio Frequency Fingerprinting methods have been proposed so far, as a support for multi-factor authentication or even on their own, practical solutions are still a challenge. The accuracy results achieved with even the best systems using expensive equipment are still not sufficient on real-life systems. Our approach proposes a hybrid protocol that can save energy and computation time on the IoT devices side, proportionally to the accuracy of the Radio Frequency Fingerprinting used, which has a measurable benefit while keeping an acceptable security level. We implemented a full system operating in real time and achieved an accuracy of 99.8% for the additional cost of energy, leading to a decrease of only ~20% in battery life.

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Compliance as a Cost-Effective System of Interaction Between Business and Government

Journal of Business Ethics ◽

10.1007/s10551-021-04890-5 ◽

2021 ◽

Author(s):

Nikolay I. Dorogov ◽

Ivan A. Kapitonov ◽

Nazygul T. Batyrova

Keyword(s):

Cost Effective ◽

Effective System

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Dominance of Fossil Fuels in Japan’s National Energy Mix and Implications for Environmental Sustainability

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18147347 ◽

2021 ◽

Vol 18 (14) ◽

pp. 7347

Author(s):

Tomiwa Sunday Adebayo ◽

Abraham Ayobamiji Awosusi ◽

Seun Damola Oladipupo ◽

Ephraim Bonah Agyekum ◽

Arunkumar Jayakumar ◽

...

Keyword(s):

Economic Growth ◽

Sustainable Development ◽

Natural Gas ◽

Co2 Emissions ◽

Environmental Sustainability ◽

Least Square ◽

Kuznets Curve ◽

Gas Oil ◽

Energy Mix ◽

Ordinary Least Square

Despite the drive for increased environmental protection and the achievement of the Sustainable Development Goals (SDGs), coal, oil, and natural gas use continues to dominate Japan’s energy mix. In light of this issue, this research assessed the position of natural gas, oil, and coal energy use in Japan’s environmental mitigation efforts from the perspective of sustainable development with respect to economic growth between 1965 and 2019. In this regard, the study employs Bayer and Hanck cointegration, fully modified Ordinary Least Square (FMOLS), and dynamic ordinary least square (DOLS) to investigate these interconnections. The empirical findings from this study revealed that the utilization of natural gas, oil, and coal energy reduces the sustainability of the environment with oil consumption having the most significant impact. Furthermore, the study validates the environmental Kuznets curve (EKC) hypothesis in Japan. The outcomes of the Gradual shift causality showed that CO2 emissions can predict economic growth, while oil, coal, and energy consumption can predict CO2 emissions in Japan. Given Japan’s ongoing energy crisis, this innovative analysis provides valuable policy insights to stakeholders and authorities in the nation’s energy sector.

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A cost-effective system for the aerobic stabilization and disposal of waste activated sludge solids

Water Research ◽

10.1016/0043-1354(82)90073-2 ◽

1982 ◽

Vol 16 (5) ◽

pp. 535-542 ◽

Cited By ~ 5

Author(s):

Linvil G. Rich

Keyword(s):

Activated Sludge ◽

Cost Effective ◽

Waste Activated Sludge ◽

Aerobic Stabilization ◽

Effective System

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Analysis of Material Behaviour in Experimental and Simulative Setup of Joining by Forming of Aluminium Alloy and High Strength Steel with Shear-Clinching Technology

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.966-967.549 ◽

2014 ◽

Vol 966-967 ◽

pp. 549-556 ◽

Cited By ~ 5

Author(s):

Martin Müller ◽

Réjane Hörhold ◽

Marion Merklein ◽

Gerson Meschut

Keyword(s):

High Strength ◽

Cost Effective ◽

Metallic Materials ◽

Material Behaviour ◽

Transportation Sector ◽

Reference Process ◽

Key Factor ◽

Mechanical Clinching ◽

Safety Parameters ◽

Systematic Development

In transportation sector the reduction of moving masses without the decrease of safety parameters is a key factor for future economic success. One possible approach for this is the use of different metallic materials in composite construction. Therefore, it is essential to establish a reliable component connection by means of suitable and cost-effective joining technologies. Mechanical joining technologies such as self-piercing riveting and mechanical clinching have proven to be effective methods for joining lightweight materials like aluminium and ductile steels. As these technologies require formability or pre-holing of the joining partners, the field of application is limited by the mechanical properties of the joining partners. Great potential for joining hot stamped steels, which have a very low elongation at fracture and therefore a low formability, offers the shear-clinching technology. For a systematic development of the shear-clinching technology, detailed investigations of the process are required. This paper presents an analysis of the material behaviour during the shear-clinching process and the reference process – clinching with pre-hole.

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