Abstract

Although Concentrated Solar Power (CSP) is one of the promising renewable energy technologies, several technical and economic challenges should be addressed. One of the major issues associated with Concentrated Solar Power technologies is the reliability limitation of the plant in the stand-alone configuration. Therefore, Concentrated Solar Power systems can be integrated with either thermal energy storage (TES) or a fossil-fuelled power assist FFPA). However, initial and maintenance costs and emission production are the main challenges for the developing countries. Integrating biofuel/biogas with CSP increases the renewability while solar irradiation is in absent. The paper main objective is to perform a feasibility study of integrating a biofuel based gas turbine power units in a Concentrated Solar Power plant for electricity and water cogeneration. The study includes the thermodynamics analysis and assessment of three biofuels, namely, Jatropha oil, castor oil, and palm oil. In addition, a cost lifecycle, sensitivity, and Monte Carlo analyses were performed. The results showed that Castor oil had a better performance in terms of efficiency and carbon dioxide emissions with a maximum daily freshwater production of 181,000 m³/day. The proposed integration resulted in a levelized cost of water that is lower than the water tariff in the UAE by $1.39/m³ with a payback period of 5 years.

Abstract

An approach for life-cycle-based sustainability assessment for innovative energy technologies was developed that includes Life Cycle Assessment, economic assessment and selected social indicators, i.e. acceptance, patents and added value. As a case study for this approach, hydrogen supply by wind powered electrolysis was assessed and different distribution options to its final use in fuel cell vehicles were compared. First results of the Life Cycle Assessment show that lowest environmental impacts are caused by transporting hydrogen in pipelines, which is also the most cost-effective option. The preliminary survey about hydrogen refuelling stations showed that the fear of explosions is most relevant to people. Regarding added value, it could be revealed that a slight shift from domestic to more globalised expenditures is to be expected in the future. It can be concluded that hydrogen supply by pipelines is the most sustainable option. However, for the implementation of this technology, social issues such as acceptance of hydrogen filling stations and decrease of local employment have to be addressed.

Abstract

Building simulation software can provide a reliable prediction of the building environmental response, however, in historical building simulations the uncertainty increases due to the lack of information and the incorrect choice of the numerical model. In this work, the moisture buffering effect is investigated using two different models in EnergyPlus software. The analysis shows that the selection of the moisture buffering calculation method highly affects the simulation results and the set-up of some input variables during the calibration phase. In detail, the use of the Effective Capacitance model could overestimate the effects of the infiltration in terms of mixing ratio, leading to the adoption of a lower value of air change rate for the model validation (about 3 times in the case study analysed). Such phenomena particularly affect historical buildings, generally characterized by massive structures and many furnishings.

Abstract

This study aimed at designing, prototyping and testing the effectiveness of a solar disinfection system for improved rural household water treatment. The system was constructed using local materials. The effectiveness and efficiency of the system to kill microorganisms were determined by using contaminated raw water samples collected from rural areas. The prototype raised the bottle water temperature from 24.3 to 66 °C. After 3 hours of exposure to intense sunlight, the water samples registered no total and faecal coliform counts in line with allowable drinking water limits by Malawi Standards and the World Health Organization. When loaded with 12 L of the contaminated water, the system scored a 10.2 % efficiency. The prototype reached disinfecting temperature faster (80 minutes) under intense sunlight conditions and worked effectively well with water of low turbidity levels. The prototype was cost-effective and easy to use, hence to be promoted for improved rural household water treatment.

Abstract

As decentralized electricity generation is supporting grid development into the prosumer era, this paper investigates the economic viability of adding batteries to residential microgrids powered by photovoltaic units, under various electricity pricing schemes. Batteries bring the benefits of grid-stabilization and congestion relief, and they are also becoming cheaper. The problem identified is that the main grid effectively acts as a lossless storage system, especially under the net-metering scheme, whereas using a battery involves investment costs and energy losses. This mismatch is addressed by analysing residential microgrid projects under seven tariff designs, each in seven countries of the European Union, and compare the economic viability of photovoltaic systems with and without batteries. The findings show that the conditions most favourable to batteries are given by a capacity tariff scheme allowing price arbitrage. Based on these findings, the paper discusses possibilities for further support in order to bring the economic viability of microgrids with batteries on par with that of microgrids without batteries.

Abstract

The United Nations Sustainable Development Goals aim to ‘do more and better with less’, with numerous calls to action arising from the business sector concerning the substantial reduction of targeted types of commercial and industrial waste. Emanating from the original work on closing material loops by McDonough and Braungardt in the 1990s, over the last two decades the concept of ‘upcycling’ has increased in popularity as a targeted intervention to reduce material and energy use in business processes. Essentially upcycling involves reusing, repairing, repurposing and upgrading waste material to avoid the conventional endpoint of ‘disposal’. However, upcycling is still considered a niche practice and many business enterprises remain unclear as to how to use upcycling opportunities for better management of their waste. In this paper, the authors propose a Tiered Approach to Waste Upcycling for Business, as a strategic way for businesses to close the loop within their industrial processes and production chains. The paper comprises a systematic literature review of opportunities and barriers for enabling business enterprises to close the loop through waste upcycling. The review highlights the ad hoc, champion-based and highly variable use of upcycling practices and uncovers opportunities for more systematic and streamlined practices to produce value-added products from waste material. Synthesising the findings, the authors establish three tiers of ‘macro’, ‘meso’ and ‘micro’ barriers and enablers that businesses can consider identifying upcycling opportunities for managing their waste. The authors also discuss key benefits of upcycling including improved quality and life of material, creating jobs and influencing positive consumer behaviour. The authors conclude the benefits of a structured approach to considering circular economy opportunities, towards improved waste management that is better for the bottom line, people and planet. With regard to future research in the field, the authors define a set of key theoretical constructs relating to waste upcycling, that can facilitate innovation and investigations into applying ideas.

Abstract

Hydrogen sulfide is a highly toxic by-product in the refineries. Traditional sulfur recovery units are already used, but optimization studies on them are still limited. The proposed process evaluates the possibility of a new frontier for sulfur recovery and carbon dioxide emissions reduction in refineries. The technological kernel is the regenerative thermal reactor which allows to convert hydrogen sulfide with another challenging emission, carbon dioxide, to valuable products (syngas) and harmless compound as elemental sulfur and water. The work has compared the effectiveness of the proposed technology with the traditional sulphur recovery units in terms of techno-economics and environmental impacts by proposing several sensitivity analyses on the main process parameters. Results state that it greatly improves the sustainability of the process in terms of quality of syngas produced while limiting the emissions. The economic analysis results look to be very promising for a pilot plant setup.

Abstract

This paper approaches the energy transition towards decarbonization and lower primary energy use in the steel and glass industries through the exploitation of radiant waste heat. In contrast with exhaust gases heat recovery, radiant waste heat has typically not been used. This energy waste is found in energy intensive processes in which high temperatures are reached. For instance, in the steel making process, the cast steel is red hot and emits a considerable amount of radiant energy. In this paper the conceptual design of a radiant heat capturing device is presented. This device enables the recovery of currently unused energy while solving the radiative emission-related problems. The achieved design gets to an optimized solution regarding view factors and optical properties of the involved surfaces. In this research work, those factors are optimized to maximize the amount of heat recovered by the presented device. Simulation tools are used to test different designs and define the most appropriate solution for a given case.

Abstract

Reductions in coal use and greenhouse gas emissions may be achieved through implementing biomass co-firing in existing coal-fired power plants with minor retrofits. Furthermore, the biomass may be sourced sustainably from agricultural wastes. Under direct co-firing, biomass is directly used as secondary fuel, while indirect co-firing separately processes the biomass reducing risks for equipment damage from unconventional feedstock. Despite the increased costs, this approach generates a biochar by-product that may be applied directly to soil for permanent carbon sequestration. However, these systems face uncertainties in biomass quality that may increase costs and environmental impacts during actual operations. This work develops a multi-objective target-oriented robust optimization model to design biomass co-firing networks integrating uncertainty in biomass properties with investment and operations planning. A case study is solved to demonstrate model capabilities. Monte Carlo simulation shows that the robust optimal network is relatively insusceptible to uncertainties compared to the deterministic solution.

Abstract

This study designed to optimize the operating parameters of the Fenton process in removing acetic acid from food processing using Response Surface Methodology module in the Design of Expert for sustainable water reuse. Optimum operating conditions needed for the highest removal efficiency of 95.2% and 84.7% for color and chemical oxygen demand respectively were found to be at hydrogen peroxide concentration of 0.004 mol/L, ferrous iron concentration of 0.02 mol/L, initial pH of 3.45, and reaction time of 149.08 min for color. While, chemical oxygen demand had a maximum of around 84.7% removal efficiency that could be obtained at a hydrogen peroxide concentration of 0.014 mol/L, ferrous iron concentration of 0.051 mol/L, initial pH of 2.04, and reaction time of 144.58 min. The results showed that the Fenton process via Response Surface Methodology, at a certain level, may be used as a useful technology for pre- and post-treatment of wastewater from food processing for water scarcity as reclaimed water.

Abstract

In the near future, cities will have to supply innovative and high value-added mobility services, that shall be sustainable in terms of environmental impact, traffic management and energy efficiency. This represents a great challenge: transportation accounts for 20% of the global energy consumption, with a large share in urban areas (around 40% of total transport consumption). One of the most promising solutions to reduce congestion, energy consumption and air pollutants in highly-populated areas is Ride Sharing. Ride Sharing systems aim to bring together travellers with similar itineraries and time schedules, thus providing significant societal and environmental benefits, such as reducing the number of cars used for personal travel and improving the utilization of available seat capacity (also defined “occupancy rate”). This paper examines the impact of Ride Sharing by developing an enhanced transport model in Visum, which takes into account the shareability of passengers mobility patterns. The model is applied to the Milan Metropolitan Area, which represents an interesting test case for two main reasons: first, its high population density and strong transport offer and second, the large amount of information and data available on passengers mobility. The paper assumes an optimal 20% participation rate to Ride Sharing and estimates its benefits in terms of congestion reduction, energy efficiency and environmental impact. The COPERT software is used to estimate Carbon Dioxide emissions and fuel consumption savings. The simulation results show that Ride Sharing brings a sort of rebound effect, since there is an increase in passengers traveling by car. However, the overall effect is a reduction in the number of vehicles used, with consequent reductions in vehicle kilometers travelled (-3.8%). This translates into 6% energy savings and 6% Carbon Dioxide emissions reduction. Some policy recommendations are provided to develop Ride Sharing in order to increase the effectiveness of this system while restraining side effects.

Abstract

Wastewater treatment and post-treatment drying techniques play a crucial role on the fertilizer value of biosolids. The aim of this study was to investigate: the nitrogen fertilizer value of biosolids from selected biosolid treatment and post treatment dewatering techniques (a) and the effect of drying depth and time on the nitrogen content of biosolid (b). To achieve the first aim, laboratory nitrogen mineralization study was conducted using thermally-hydrolysed-biosolid, activated-biosolid, and anaerobically-digested-biosolids. To achieve the second aim five drying depths were tested (5, 10, 15, 20 and 25 cm). Nitrogen release per tonne biosolid applied was highest for activated (24 kg), and lowest for anaerobically-digested-biosolid (6 kg). Highest total nitrogen was reported for 10 cm drying depth (3.63%) (4 weeks) and lowest for 25 cm (2.64%) (8 weeks). Selection of appropriate biosolid treatment and dewatering technique is key to improve fertilizer value of biosolids.

Abstract

The future ability of urban centres in Australia and around the globe to adapt and respond to big challenges of climate change, economic development, and social inclusion, will depend on how well we integrate and embed them within these built environments. Such a complex agenda presents a major collective challenge for designers, planners and engineers to address with politicians, developers, financiers and community leaders. Refocusing design requires collaborative processes and co-creation in a design space currently dominated by siloed approaches to traffic management, transport planning, precinct design and engineering, architecture and landscaping. With the aim of bridging these silos, an interdisciplinary research team has synthesised and then applied a set of principles of design to a range of development scenarios with the aim of delivering sustainable urban centre outcomes. This paper uses the lens of the Theory of Urban Fabrics to present a place making Sustainable Centres Framework created by the authors, comprising 7 principles and 21 associated practices of design. This formed a critical first step for a national sustainable centres research project underway at the time. The paper then presents the findings of a two-phase investigative study to apply the framework to four place-oriented urban regeneration initiatives (i.e. case study sites) that were endeavouring to enable transit activated corridors with local micro-mobility linkages, in Townsville, Sydney, Melbourne and Perth. The first phase of the study comprised a desk-based application of the Sustainable Centres Framework to the four sample urban fabric types observed the case study locations. The second phase involved detailed sense-checking of the framework in the one of the case study locations (Townsville), through stakeholder workshops. The findings provide insights into opportunities and considerations for managing the complexity of urban regeneration projects. The authors discuss the potential for the Framework to inform planning tools and decision support tools, and opportunities to further refine the Framework.

Abstract

The absorber section is a critical component in solar thermal collectors and is responsible for converting electromagnetic radiation into sensible thermal energy. The optical properties of the surface of the absorber dictates the effectiveness of this conversion. In this work, a manufacturing process is designed to provide bulk surface treatment for solar absorber plates in order to enhance their radiative properties. The process utilizes a novel approach of graphene synthesis and simultaneous deposition via high pressure blasting of graphite. The results show enhanced spectral, thermal and electrochemical performance of the absorber due to the turbostratic nature of graphene adhesion to its surface, especially when three blasting passes are used. The absorptivity of the absorber exhibited a 7% increase when three passes were applied on its surface. Using graphene has also enhanced the corrosion resistance of the absorber plate. This manufacturing system will provide a facile yet effective treatment of absorbers with various degrees of automation. Applied as a final layer, the process can be retrofitted to existing manufacturing facilities with minimum overhead costs.

Abstract

Detailed demand profiles for the residential sector are an important prerequisite for the improvement of building energy efficiency and the development of polygeneration systems. Therefore, the aim of this paper is to provide a generic pattern for each energy demand required for a single-family dwelling. The data of electricity, domestic hot water and freshwater were obtained through literature reported methods of demand profile estimation, whereas heating and cooling have been estimated by TRNSYS software simulation. All methods provide energy consumption profiles with 1-hour time step along 1-year period. Daily, weekly and yearly results are presented. The total dwelling consumption amounts to 3,866 kWh/y of electricity, 941 kWh/y of heating, 1,450 kWh/y of cooling, 41 m³/y or 2,090 kWh/y of domestic hot water and 110 m³/y of freshwater. Primary energy saving can achieve up to 13,917 kWh/y in case of renewable energy use and a higher comfort level is felt by the users during summer.

Abstract

The United Nations Sustainable Development Goal 9 on building resilient infrastructure highlights the urgent need for enabling evidence-based decision making for Infrastructure Asset Management supported by targeted platforms such as digital engineering and digital earth. In this paper the authors argue that an Asset Information Requirement matrix is an essential decision support tool for authorities and practitioners to evaluate right time, right place use of infrastructure data for resilient outcomes. The authors present an exploratory study that synthesizes the experiences of senior asset management decision-makers from road research institutes, state and local government bodies based in South East Queensland, Australia. The findings are discussed  in relation to: digital engineering for managing complex data; current practice and outlook; key asset information requirements; and data structures, interactions and interdependencies. The authors present an ‘Asset Information Requirement Matrix’ that categorises 66 data requirements  across four key infrastructure data types (including 13 information categories), and asserts the relevance of these data requirements for the six key phases of planning, design, construction, acquisition, operations and end-of-life treatment. The authors also present an ‘Asset Interaction Matrix’ which depicts the temporal, spatial and logical relationships between the 13 information categories. The authors conclude the importance of these asset matrices to leverage digital engineering for resilience infrastructure outcomes. The two matrices create a common language platform for engaging in digital engineering conversations, wherein authorities and practitioners can establish clear arrangements for measuring and monitoring road infrastructure through its life cycle.

Abstract

While traces of pharmaceuticals have been found in the environment, the pharmaceutical industry produces waste streams high in pharmaceutically active compounds concentration along with other components such as salts. This work investigated the removal of three common pharmaceuticals, carbamazepine, ibuprofen, and diclofenac, at concentrations found in the pharmaceutical industry, under different monovalent salt concentrations of sodium chloride using a commercially available nanofiltration membrane. The influence of a monovalent salt concentration and temperature on the removal were determined. Pharmaceutical rejection was found to be dependent on the compounds’ molecular weights, charge, and hydrophobicity. Diclofenac and ibuprofen rejections were found to be high (90-99%) and (85-96%) respectively, and the rejection increased with increasing salt concentration. Meanwhile, moderate retention values were found for the neutral carbamazepine (65-77%) and these values decreased with increasing salt concentration, and also decreased with increasing temperatures. A threshold salt concentration was found at which these effects were buffered or even reversed.

Abstract

Water, Energy, and Food sectors are interlinked in a nexus wherein actions relevant to one sector can often influence other sectors to a high degree. Globally, there has been a growing focus on ensuring water, energy, and food security in different kinds of frameworks and models. The current research aims to describe the complex interlinks between the three sectors by evaluating the challenges and opportunities in the following domains: policy, management, and technology. The hypothesis is to provide a basic practice framework to secure better outreach to tackle the interlinks and mismatches within the nexus elements. The methods used a dynamic framework through a transdisciplinary team; the team divided the nexus into six sub-sectors and collecting the primary data through fieldwork interviewing 22 stakeholders and secondary data of 211 literature. The approach of complex adaptive systems and evolving mental models have been used to analyse and develop the framework. The results show that interlinks within the water, energy, and food nexus are quite challenging to be identified since each region has different needs. However, the customized framework covered the gaps holistically, which can be used as a fundamental practice guideline. The study also proposed practical solutions and highlighting the opportunities to secure the future of sustainable development goals.  

Abstract

Abstract

Skygardens are increasingly being seen as design interventions for improving the social, economic and environmental values of a building. Additionally, the integration of vegetation within the building space can have health benefits for occupants, occupants’ satisfaction while improving the air quality. However, the aerodynamic response of skygarden vegetation must be understood in detail to assist designers in the selection and arrangement of species for creating a conducive environment for occupants. The current study analyses nine different vegetation configurations within a high-rise skygarden to determine the aero-thermal performance. Computational fluid dynamics simulations were carried out using the standard k-Ɛ method, where the vegetation was modelled as a porous zone with cooling capacity. The results indicate that vegetation can attenuate high wind speeds within comfort levels at occupants’ height, as well as reduce temperatures by over 1 °C in the wake of the vegetation. Whereas the performance improves with higher number of trees, but when considering limited vegetation space, the relative performance of a single-row configuration is better than a double row of trees along the skygarden edge.