The desire to combat the negative externalities of climate change and its variability has gained a lot of ground over the last few decades. This has resulted in the development of several approaches among which is the UI GreenMetric university ranking developed in 2010. In light of this, this article seeks to examine the performance of African higher education institutions on the ranking table and the impact they have had on their respective countries. To achieve this, this article compared performance scored between participating universities, carbon dioxide (CO₂) emission trends, and renewable energy consumption trends. The findings paint a picture of poor performance across each of the categories measured under the UI GreenMetric ranking. However, there was some marginal decline in CO₂ emissions as well as an increase in renewable energy consumption for some participating countries. The findings reveal that participation of African universities in the ranking has been very low. Institutionalizing green campus initiatives by African governments to make it a must for a higher education institution to adopt such strategies was recommended. The study also recommends an increase in sup- port for research in the area of green technologies, methods, and procedures in Africa so as to create enough awareness and education on the topic.

Corn cobs can be processed chemically to generate new products for electricity employing a simple, low-cost, and environment friendly method. In this article, silicon carbide (SiC) and activated carbon can be synthesized from corn cobs via sol–gel and a chemical activation method, respectively. SiC was synthesized by reacting the synthesized silica and activated carbon with magnesium powder, which served as catalyst at 600 oC. The SiC was doped with varying amount of Al2O3 (0.01, 0.015, 0.02 and 0.1 g), a p-type dopant, via solvothermal synthesis. The undoped SiC was characterized using Scanning Electron Microscopy with Energy Dispersive X-ray Spectroscopy (SEM-EDX) and Fourier Transform Infrared (FTIR). Then, the band-gap energy and conductivity of undoped SiC and p-doped SiC were determined. SEM-EDX and FTIR analysis confirmed the presence of Si–C bond in the synthesized SiC from corn cob. It was observed that p-doped SiC absorbs higher energy in the visible region than undoped SiC. FTIR analysis confirmed the incorporation of the aluminum in the SiC. UV–vis spectros-copy confirmed that the synthesized p-doped SiC exhibits higher absorbance compared with undoped SiC. Aluminum doping also increased absorption bands on the visible region making it more efficient for potential application in photovoltaic (solar) cells because of the decreased band-gap energy and increase in conductivity of p-doped SiC. The ratio of 1:1–2 (SiC:Al) showed the lowest band-gap and highest conductivity with a value of 1.57–1.58 eV and 0.080–0.082 mS/cm compared with the amount of other p-dopants. Statistically, it was found that the 1:1–2 ratio of SiC:Al can be an effective p-junction for the application in photovoltaic (solar) cells.

This work presents a new method for identifying the bubbling regime of a fluidized bed gasification reactor. The method has been developed using experimental measurements and a computational model. Pressure drops are measured in experiments, and pressure drop as well as solid volume fraction fluctuations are calculated by implementing the model. experiments are carried out with sand and limestone particles of mean diameter 346 µm and 672 µm, respectively. A computational particle fluid dynamics (CPFD) model has been developed for the reactor and implemented using a commercial CPFD software Barracuda VR. The model is validated against experimental measurements. The validated model is used to analyse the fluctuation of pressure drop and solid volume fraction as a function of superficial air velocity. The change in standard deviation of pressure drop and solid volume fraction fluctuation is used to predict the transition from one regime to another. The method can be used in the design and operation of a bubbling fluidized bed gasification reactor. The results show that the minimum fluidization velocity for sand and limestone are 0.135 m/s and 0.36 m/s, respectively and are independent of the particle aspect ratio. Both types of particle beds make the transition into bubbling regime as soon as they get fluidized. The bed aspect ratios have almost no effect on the onset of bubbling fluidization regime. The slugging velocity decreases with increasing aspect ratio for both types of particles. The operating range of the bubbling fluidized bed for sand particle is 0.2–0.4 m/s and 0.5–0.8 m/s for the limestone particles.

Following the COP21 conference in Paris, most of the world’s industrialized countries, as well as emerging markets, pledged to reduce or stabilize their greenhouse gas (GHG) emissions in light of increasing concerns regarding climate change [1]. The necessity to decrease ghg emissions will have implications on the consumption patterns of different types of energies around the world. apart from the obvious need to replace part of the increasing fossil fuel consumption in transportation (including road, rail, air and sea), there is a growing demand in other sectors as well, such as for electricity production, heating and cooling. Many opportunities are being investigated to address some of the issues related to this green energy transition, including the increased harnessing of alternative energy sources such as wind, solar, hydro, geothermal and biomass. Despite varying potential for each of the mentioned energy sources to help replace or supplement fossil fuels, only biomass currently has the potential to address most of these needs without requiring significant changes to existing energy distribution networks. for example, bio-mass can be burnt to generate combined heat and power, but it can also be used as a source of carbon to produce biofuels. In the latter case, biofuels such as ethanol could be blended into the existing fuel pool as well as distributed and utilized in engines without requiring significant modifications to the existing chain of distribution. This adaptiveness is not necessarily the case when considering electric vehicles (EV), although they are also of crucial importance towards collectively reducing ghg emissions. This manuscript will review the Biorefinery Done right-concept, developed by the company RéSolve Énergie in close collaboration with the Biomass Technology laboratory. This simple feedstock-agnostic technology allows conversion of any type of residual biomass (including but not limited to softwood bark) to three-types of biofuels. The first objective is to take advantage of the carbohydrate content in the biomass through hydrolysis of the constitutive hemicellulose and cellulose. The fermentable sugars are then converted to ethanol, achieved without any constraints, since the RéSolve process generates a hydrolysate with very low inhibitor levels. The lignin recovered from the process is essentially unmodified lignin and after washing, it is pelletized. Pellets, containing the most energetic components of the lignocellulosic biomass, can provide up to 26 GJ/tonne. Finally, the non-fermentable sugars (C5), as well as the lignin that does not comply with grade a lignin characteristics, are predigested for utilization in a classical biomethanation system. Hence, through this approach, 100% of the carbon from the biomass is converted into commercial products, which at this point are all related to the energy market.

The enhancement of heritage resources helps to promote conservation, contributes to more significant and better protection, and favors the efficient use of these resources. Many heritage works and liabilities linked to mining activity are abandoned, causing the deterioration of heritage resources that may become environmental liabilities over time. this work aims to develop strategies for the development of the Mining-industrial heritages through participatory methods for geomining enhancement and development of places in the Zaruma-Portovelo area. The proposed methodology consists of: (i) the creation and development of a database with several publications and documents that register the Mining-industrial heritage sites; (ii) the assessment of mining-industrial sites based on criteria or methodologies proposed by other authors; (iii) focal group work considering: (a) the identification and cataloging geosites of interest, (b) the creation and/or development of museums, tourist mines, mineral routes or geoparks in which the natural and geological-mining factors complement each other and (iv) SWOT analysis and matrix which provides several strategies for value-making of geomining heritage and its promotion in the development of geotourism in a project proposal for Zaruma and its surroundings. in conclusion, this work includes twelve unified mining sites in the Proposal for Geopark ‘Ruta del Oro,’ as a strategy to guarantee the conservation of heritage values and contribute to local development and geotourism.

Geothermal energy is developing with high progress to provide clean energy production standards at a world-wide scale. These projects are characterized with high risk level associated with drilling methods, resource existence, uncertain heat water temperature and its chemistry. The risk mitigation scenarios are crucial to avoid investment failure. Presented paper is a case study of geothermal investment in Trzęsacz, located in the Baltic coastline in Poland, where predicted heat water (38°C) was planned to be used for leisure, swimming and balneological purposes. The final effect of test drilling was disruptive. Thermal water has temperature 27°C and is not enough to fulfill needs of planned water park facilities and hot springs recreational proposals. The concept had to be revised. The amount of wasted water and embodied energy were recognized as a high entropy problem. In the spirit of syntropic development model, an idea to consume unwanted geothermal water and to treat it as useful local resource for aquaculture purposes was taken into consideration. That way the Jurassic Salmon Farm realization in Janowo in 2015, the first in the world salmon fishery based on geothermal resources, became an inspiration for future fishery deliberation, the fastest growing food sector globally. The Farm was realized 5 km from operating geothermal well, supported with EU funds and research programme led by West – Pomeranian University of Technology in Szczecin. The greenfield investment powered by renewable energy, based on biosafety and industrial ecology rules is an example of the 21st century bioculture. This one moved to urban areas may comply with broad sense to the city aquaculture, aquaponics or urban agriculture, with improvement of the risk reduction strategy in geothermal energy investments. This is the potential to be used by local communities, which can favor synergy effect on the way to regenerative design and syntropic development model.

This article describes an expert system of probability type for diagnostics and state estimation of steam turbine technological subsystems’ components. The expert system is based on Bayes’ theorem and permits one to troubleshoot the equipment components, using expert experience, when there is a lack of baseline information on the indicators of turbine operation. Within a unified approach, the expert system solves the problems of diagnosing the flow steam path of the turbine, bearings, thermal expan- sion system, regulatory system, condensing unit, and the systems of regenerative feed-water and hot water heating. The knowledge base of the expert system for turbine unit rotors and bearings contains a description of 34 defects and 104 related diagnostic features that cause a change in its vibration state. The knowledge base for the condensing unit contains 12 hypotheses and 15 pieces of evidence (indications); the procedures are also designated for 20 state parameters’ estimation. Similar knowledge bases containing the diagnostic features and fault hypotheses are formulated for other technological subsystems of a turbine unit. With the necessary initial information available, a number of problems can be solved within the expert system for various technological subsystems of steam turbine unit: for steam flow path, it is the correlation and regression analysis of multifactor relationship between the vibration and the regime parameters; for thermal expansion system, it is the evaluation of force acting on the longitudinal keys depending on the temperature state of the turbine cylinder; for condensing unit, it is the evaluation of separate effect of the heat exchange surface contamination and of the presence of air in condenser steam space on condenser thermal efficiency performance, as well as the evaluation of term for condenser cleaning and for tube system replacement. With the lack of initial information, the expert system formulates a diagnosis and calculates the probability of faults’ origin.