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The public‐private partnership (PPP) procurement approach enables the development and management of public infrastructure and services through leveraging private capital, management expertise, and creative commercial skills. This approach, pursued by the Ghanaian Government in the development and management of water supply services, contains a plethora of risks resulting from the complexity and dynamic interactions between municipal and central governments (pursuing monetary and political goals), public movements, private water operators, and international donors pursuing their own objectives. The paper seeks to increase awareness of the risks that can erode or reduce potential benefits of PPPs in the water supply sector.

A research approach integrating a literature survey and case study is adopted. A rigorous literature review of PPP risks is first undertaken. Based on six case studies carried out in the Ghanaian water supply sector, this paper identifies and categorises the risks specific to water supply PPP contracts in Ghana.

A total of 40 risk factors are identified, classified into eight categories based on their sources and their content presented in detail. Common risks which are worth practitioners' attention include weak regulatory and monitoring regime; financing; absence of risk allocation mechanisms; inexperience in PPPs; public opposition; delayed and non‐payment of bills, etc.

A comprehensive list of risks associated with water supply projects in Ghana has been identified. This list will aid practitioners, municipal and central government authorities, and the domestic and the (potential) international private sector audience in managing risks involved in such projects.

The purpose of this paper is to analyze the performance of the gas turbine cycle integrated with solid oxide fuel cell technology. In the present work, intermediate temperature solid oxide fuel cell has been considered, as it is economical, can attain an activation temperature in a quick time, and also have a longer life compared to a high-temperature solid oxide fuel cell, which helps in the commercialization and can generate two ways of electricity as a hybrid configuration.

The conceptualized cycle has been analyzed with the help of computer code developed in MATLAB with the help of governing equations. In this work, the focus is on the performance investigation of a Gas turbine intermediate temperature solid oxide fuel cell hybrid cycle. The work also analyzes the performance behavior of the proposed cycle with various design and operating parameters.

It is found that the power generation efficiency of the IT-SOFC-GT hybrid system reaches up to 60% (LHV) for specific design and operating conditions. The cycle calculations of an IT-SOFC-GT hybrid system and its conceptual design have been presented in this work.

The unique feature of this work is that IT-SOFC has been adopted for integration instead of HT-SOFC, and this work also provides the performance behavior of the hybrid system with varying design and operating parameters, which is the novelty of this work. This work has significant scientific merit, as the cost involved for the commercialization of IT-SOFC is comparatively lower than HT-SOFC and provides a good option to energy manufacturers for generating clean energy at a low cost.

This paper aims to evaluate the effect of optimal use of rooftop photovoltaic (PV) systems on improving the loss of life (LOL) of distribution transformers, reducing power losses as well as the unbalance rate of the 69-bus distribution network.

The problem is studied in three scenarios, considering different objective functions as multi-objective optimization in balanced and unbalanced operations. Meta-heuristic golden ratio optimization method (GROM) is used to determine the optimal size of the rooftop PV in the network.

The simulation results show that in all scenarios, the GROM by optimally installing the rooftop PV is significantly capable to reduce the transformer distribution loss of loss, unbalance rate and power loss as well as reduce the temperature of the oil and transformer winding. Also, the lowest %LOL, power loss and unbalance rate occurred in the second scenario for the balanced network and first scenario, respectively. In addition, the results showed that the unbalance of the network results in increased power losses and LOL of the distribution transformer.

The better capability of GROM is proved compared with the grey wolf optimization algorithm with better objective function and by achieving better values of LOL, unbalance rate and power loss. The results also showed that the %LOL, unbalance and power losses are weakened compared to without considering the PV cost but the achieved results are realistic and cost-effective.

This paper aims to examine the role of technological Innovation in ensuring resource sustainability in the water, energy and food (WEF) nexus, as there exists a shortage of statistical research on the extent of the influence of technological Innovation on the WEF nexus.

The study used a quantitative research method, using a well-structured questionnaire to collect data from management staff in the WEF departments in South Africa. The collected data were analyzed by using mean score ranking, exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) for structural equation modelling (SEM).

The findings show that the technological process of technological innovation is significant for resource sustainability. The result also showed that technological innovations directly and statistically significantly affect WEF nexus. The EFA resulted in three components of WEF nexus product innovation, WEF nexus process innovation and WEF nexus novel innovations. Furthermore, the CFA and SEM analysis reveals that six technological innovation indicators influence the sustainability of the nexus: smart water metering technology, smart metering technology, food quality monitoring technology, agricultural technology solutions, new technological design and eco-friendly WEF products.

The sustainability of these three inevitable resources for man’s survival is dependent on technological innovations, and this study has shown the major categories of innovations needed, thus establishing a pathway for engineering design.

This paper aims to empirically investigate the differences and similarities on the implementation constraints in public–private partnership (PPP) in developing and developed economies/countries, represented by Ghana and Hong Kong, respectively.

A questionnaire survey was conducted with relevant experienced PPP practitioners in Ghana and Hong Kong. One hundred and three completed questionnaires were received for analysis. Kendall’s coefficient of concordance analysis, mean score ranking, Mann–Whitney U test and quartile grouping were used for data analysis.

The results show six implementation constraints with significant differences. Constraints related to the general investment climate of PPP projects (i.e. ecological conditions of PPP) are ranked higher in Ghana than in Hong Kong, whereas constraints related to the organisation and negotiations of PPP projects are higher in Hong Kong than in Ghana. Further, two constraints, lengthy delay in finalising negotiations and lengthy delay due to political debate, are very critical in both jurisdictions, whereas “negative public perceptions on PPP transactions” and “high use of unsolicited proposals” are of less challenge in the implementation of PPP in both jurisdictions.

The findings of this study contribute to knowledge on the international best practices of PPP. In addition, international private bidders would be informed of the mitigation measures to adopt when engaging in PPP arrangements in any part of the world, whether in a developing or developed economy country.

The aim of this study is to examine the effect of carbonization on the surface and its influence on heavy metal removal by water hyacinth based carbon.

Dried water hyacinth stem was used as precursor to prepare carbon based adsorbent by pyrolysis method. The adsorbent proximate (ash, volatile matter and fixed carbon) and elemental (carbon hydrogen nitrogen sulfur) composition, surface area, pore size distribution, surface chemistry was examined and compared.

The results demonstrated that through carbonization in comparison to dried water hyacinth stem, it increased the surface area (from 58.46 to 328.9 m²/g), pore volume (from 0.01 to 0.07 cc/g), pore size (from 1.44 to 7.557 Å) thus enhancing heavy metal adsorption. The metal adsorption capacity of Cd, Pb and Zn was measured and analyzed through induced coupled plasma-mass spectrometer. At metal concentration of 0.1 mg/l adsorption rate for Cd, Pb and Zn was 99% due to increased large surface area, coupled with large pore size and volume. Furthermore, the adsorbent surface hydroxyl group (OH⁻) enhanced adsorption of positively charged metal ions through electrostatic forces.

It is presumed that not only adsorption with synthetic wastewater but real wastewater samples should be examined to ascertain the viability of adsorbent for commercial application.

There are little or scanty data on the effects of carbonization on water hyacinth stem based carbon and subsequent effects on heavy metal removal in effluents.

Wastewater treatment plants (WWTPs) have long-time environmental impacts. The purpose of this paper is to assess the environmental footprint of two advanced wastewater treatment (WWT) technologies in a life cycle and sustainability perspective and identify the improvement alternatives.

In this study life cycle-based environmental assessment of two advanced WWT technologies (moving bed biofilm reactor (MBBR) and sequencing batch reactor (SBR)) has been carried out to compare different technological options. Life cycle impacts were computed using GaBi software employing the CML 2 (2010) methodology. Primary data were collected and analysed through surveys and on-site visits to WWTPs. The present study attempts to achieve significantly transparent results using life cycle assessment (LCA) in limited availability of data.

The results of both direct measurements in the studied wastewater systems and the LCA support the fact that advanced treatment has the best environmental performance. The results show that the operation phase contributes to nearly 99 per cent for the impacts of the plant. The study identified emissions associated with electricity production required to operate the WWTPs, chemical usage, emissions to water from treated effluent and heavy metal emissions from waste sludge applied to land are the major contributors for overall environmental impacts. SBR is found to be the best option for WWT as compared to MBBR in the urban context. In order to improve the overall environmental performance, the wastewater recovery, that is, reusable water should be improved. Further, sludge utilisation for energy recovery should be considered. The results of the study show that the avoided impacts of energy recovery can be even greater than direct impacts of greenhouse gas emissions from the wastewater system. Therefore, measures which combine reusing wastewater with energy generation should be preferred. The study highlights the major shortcoming, i.e., the lack of national life cycle inventories and databases in India limiting the wide application of LCA in the context of environmental decision making.

The results of this study express only the environmental impacts of the operation phase of WWT system and sludge management options. Therefore, it is recommended that further LCAs studies should be carried out to investigate construction and demolition phase and also there is need to reconsider the toxicological- and pathogen-related impact categories. The results obtained through this type of LCA studies can be used in the decision-making framework for selection of appropriate WWT technology by considering LCA results as one of the attributes.

The results of LCA modelling show that though the environmental impacts associated with advanced technologies are high, these technologies produce the good reusable quality of effluent. In areas where water is scarce, governments should promote reusing wastewater by providing additional treatment under safe conditions as much as possible with advanced WWT. The LCA model for WWT and management planning can be used for the environmental assessment of WWT technologies.

The current work provides a site-specific data on sustainable WWT and management. The study contributes to the development of the regional reference input data for LCA (inventory development) in the domain of wastewater management.

The objective of this article is to propose the use of nuclear power to provide electricity and wide‐scale desalination to meet future population growth in Israel and a Palestinian State.

The extent of future water and power shortages in Israel and a Palestinian States expounded in the article and various methods for alleviating these shortages are explored. Comparisons are made with historical approaches.

Nuclear pebble‐bed technology is found to be the most cost‐effective way to energize future water and power needs. It is safe, non‐polluting, and terrorist resistant.

This article makes the case that abundant water and power in the Middle East is both a pre‐requisite and a stimulant for peace in the region.

This paper aims to analyze energy and exergy analysis of solar-based intercooled and reheated gas turbine (GT) trigeneration cycle using parabolic trough solar collectors (PTC) with the use of MATLAB 2018.

In the first section of this paper, the solar-based GT is validated with the reference paper. According to the reference paper, the solar field is comprising 30 modules in series and 35 modules in parallel series, where a total of 1,050 modules of PTC are taken into consideration. In the second part of this paper, the hybridization of the solar, GT trigeneration cycle is analyzed and optimized. In the last section of this paper, the hybridization of solar, intercooled and reheated GT trigeneration systems is examined and compared.

The results examined the first section, the power produced by the cycle will be 37.34 MW at 0.5270 kg/s mass flow rate of the natural gas consumption and the efficiencies of energy and exergy will be 38.34% and 39.76%, respectively. The results examined in the second section, the power produced by the cycle will be 38.4 MW at 0.5270 kg/s mass flow rate of the natural gas consumption and accordingly the efficiency of energy and exergy is found to be 40.011% and 41.763%. Where in the last section, the power produced by the cycle will be 41.43 MW at 0.5270 kg/s mass flow rate of the natural gas consumption and the energy and exergy efficiencies will be 39.76% and 40.924%, respectively.

The author confirms that this study is original and has neither been published elsewhere nor it is currently under consideration for publication elsewhere.

Improved nuclear reactor configurations that address major concerns of environmentalists and safety analysts are discussed. In addition to social acceptance, these new modes of power generation have economic potential to become the dominant producers of energy in the twenty‐first century. The class of power generation with this promise is the high temperature gas reactor (HTGR); the variant we focus on is the pebble‐bed modular reactor (PBMR). We also focus on using nuclear power as an energy source for desalinating seawater. Finally, the case is made that HTGR reactors are ideal for supplying the high‐temperature heat needed for manufacturing molecular hydrogen, a leading candidate for clean fuel consumption. These three themes are developed in a broad context with the objective of recommending policy actions dealing with global warming, public health, and economic opportunity.