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Abstract Large amounts of heat is wasted through air coolers and water coolers for cooling low temperature ( H ) recovered in the evaporator were 8.0–8.6 MW for ORC using i-pentane as working fluid and 8.2–8.3 MW for Kalina cycle, respectively. Efficiency (η) of selected systems obtained at the highest power generated (W T ) was 10.0% (W T = 862 kW) for ORC and 10.57% (W T = 996 kW) for Kalina cycle within the design boundaries. Calculated carbon dioxide (CO 2 ) emission reduction potential was 2260 t/y for ORC and 2600 t/y for Kalina system, respectively, at advantageous process conditions. Results showed that Kalina cycle provided higher efficiency and power generation ability on expense of higher system pressure (29 bar–7 bar). Economic calculations showed that the payback time is about 5.0 year for both systems.

SummaryThe German government has adopted a law that requires sewage plants to go beyond the recovery of phosphorus from wastewater and to promote recycling. We argue that there is no physical global short‐ or mid‐term phosphorus scarcity. However, we also argue that there are legitimate reasons for policies such as those of Germany, including: precaution as a way to ensure future generations’ long‐term supply security, promotion of technologies for closed‐loop economics in a promising stage of technology development, and decrease in the current supply risk with a new resource pool.

The basins of the Indus and Ganges rivers cover 2.20 million km2 and are inhabited by more than a billion people. The region is under extreme pressures of population and poverty, unregulated utilization of the resources and low levels of productivity. The needs are: (1) development policies that are regionally differentiated to ensure resource sustainability and high productivity; (2) immediate development and implementation of policies for sound groundwater management and energy use; (3) improvement of the fragile food security and to broaden its base; and (4) policy changes to address land fragmentation and improved infrastructure. Meeting these needs will help to improve productivity, reduce rural poverty and improve overall human development.

Three gray models for the radiative properties of gases were examined for their usage in oxy-combustion simulations of a full scale boiler with flue gas recycle. Fully coupled computational fluid dynamic (CFD) simulations of a full scale boiler were carried out employing the weighted-sum-of-gray-gases model (WSGGM) at air burn, dry-recycle and wet-recycle conditions. The resulting thermal and composition fields were then frozen and the radiative properties of the gaseous media recomputed employing the Exponential Wide Band Model (EWBM) and correlations for total emissivities of gas mixtures. It is shown that when high CO2/H2O ratios were encountered within the boiler such as in dry-recycle scenarios, employing emissivity correlations developed for purely CO2 media within the models can result in incorrect gas properties. The errors associated with this can be significant when there are large pockets within the furnace where the gas radiation dominates the particle radiation.

Abstract Urban planners, local authorities, and energy policymakers often develop strategic sustainable energy plans for the urban building stock in order to minimize overall energy consumption and emissions. Planning at such scales could be informed by building stock modeling using existing building data and Geographic Information System-based mapping. However, implementing these processes involves several issues, namely, data availability, data inconsistency, data scalability, data integration, geocoding, and data privacy. This research addresses the aforementioned information challenges by proposing a generalized integrated methodology that implements bottom-up, data-driven, and spatial modeling approaches for multi-scale Geographic Information System mapping of building energy modeling. This study uses the Irish building stock to map building energy performance at multiple scales. The generalized data-driven methodology uses approximately 650,000 Irish Energy Performance Certificates buildings data to predict more than 2 million buildings’ energy performance. In this case, the approach delivers a prediction accuracy of 88% using deep learning algorithms. These prediction results are then used for spatial modeling at multiple scales from the individual building level to a national level. Furthermore, these maps are coupled with available spatial resources (social, economic, or environmental data) for energy planning, analysis, and support decision-making. The modeling results identify clusters of buildings that have a significant potential for energy savings within any specific region. Geographic Information System-based modeling aids stakeholders in identifying priority areas for implementing energy efficiency measures. Furthermore, the stakeholders could target local communities for retrofit campaigns, which would enhance the implementation of sustainable energy policy decisions.

Domino reactions were designed to allow the byproduct of an upstream reaction to be internally recycled to catalyze a downstream reaction in a one-pot tandem sequence. Nitroarene reduction by In(0) generates an amine and In (III) byproducts. Addition of aldehyde followed by Danishefsky's diene or silyl ketene acetal provides access to dihydropyridin-4-ones or beta-amino esters, respectively, in yields that are comparable or superior to the reported stepwise reactions.

This chapter uses data on Intended Nationally Determined Contributions (INDCs) to examine the nature of climate change mitigation and adaptation actions being pursued in African countries and assesses the extent to which preferred mitigation and adaptation priorities advance the cause of sustainable development on the continent. The prospective synergies between mitigation and adaptation approaches and sustainable development are assessed. Also, the pathways through which resource constraints and institutional and policy environment affect Africa’s ability to mitigate and adapt to climate change are examined, as well as the degree to which these constraints are being addressed. It is argued that Africa’s ability to benefit from sustainable development synergies embedded in the mitigation and adaptation strategies in the INDCs will be greatly limited by institutional and policy environment that hinders funding, capacity building, and technological innovation systems development. The slow pace of efforts to address these impediments further erodes confidence that climate adaptation in Africa will be effective at sufficiently contributing to a reduction in climate change risks to the continent.

Currently, fossil fuels make up a significant proportion of global energy demand and cause many concerns, such as increasing greenhouse gas emission. Therefore, there is a considerable need for cost-effective, facile and efficient processing of environmental-friendly energy harvesting and storage systems. Solar energy is one of the most promising energy sources that meet the energy demand. The silicon-based solar cells exhibit competitive power conversion efficiency and dominate the solar cell market in recent years. In contrast, organic solar cells (OSCs) have emerged as promising third-generation photovoltaic devices owing to their outstanding properties such as the potential of low-cost mass manufacturing, lightweight, mechanical flexibility and easy processability. Therefore, OSCs have received growing attention from the research community. For solar cell technologies, a smectic liquid crystal C8-BTBT was selected in Chapter 3 due to its unique thermal dynamic and crystal properties. A range of ternary OSCs with and without C8-BTBT loading at gradient weight fractions were thermally treated and fabricated. In addition, the assessment of fabricated OSCs on the photovoltaic characteristics reveals the evolution of various cell parameters with annealing temperature and C8-BTBT weight fractions. The cell with 5 wt% C8-BTBT loading exhibited the best performance after thermal annealing treatment at 120 oC. Furthermore, flexible hydrogel substrates were fabricated for flexible OSCs in Chapter 4. The PHEMA hydrogel films were optimised via adjusting photopolymerisation duration under UV light. Based on the fabricated PHEMA substrates, flexible OSCs were subsequently made, whose extracted device parameters showed comparable characteristics with those in Chapter 3. Moreover, PHEMA-based OSCs can be dissolved in different types of polar solvents, which is promising for realising sustainable and recyclable solar cells. For the development of energy storage devices, asymmetric carbon nanohorns were proposed as an active material to fabricate flexible solid‐state carbon wire (CW)‐based electrochemical supercapacitors (ss‐CWECs) which exhibited high power density and ultra‐low cutoff frequency. Based on microscopy and electrochemical characterisation, the fundamental reaction mechanism in polyvinyl‐based electrolyte system was elucidated in Chapter 5, as being associated with deprotonation reaction under the acid, base, and elevated temperature conditions. In Chapter 6, by using activated carbon, multi‐walled carbon nanotubes, and single‐wall carbon nanohorns as hybrid electrode materials (5:1:1), remarkable specific length capacitance of 48.76 mF cm−1 and charge-discharge stability (over 2000 times cycles) of ss‐CWECs were demonstrated, which are the highest reported to date. Furthermore, a high‐pass filter for eliminating ultra‐low electronic noise was demonstrated, enabling an optical Morse Code communication system to be operated. vThe collective works in this thesis demonstrate novel energy conversion and storage applications with the liquid crystal in OSCs and carbon nanoparticles in supercapacitors. These results provide a step forwards in the development of energy conversion and storage devices for a more efficient energy system.

Life Cycle Assessment (LCA) has matured over the past decades and become part of the broader field of sustainability assessment. To strengthen LCA as a tool and eventually increase its usefulness for sustainability decision-making, it is argued that there is a need to expand the ISO LCA framework by integration and connection with other concepts and methods. This paper explores the potential options for deepening and broadening the LCA methodologies beyond the current ISO framework for improved sustainability analysis. By investigating several environmental, economic and social assessment methods, the paper suggests some options for incorporating (parts of) other methods or combining with other methods for broadening and deepening the LCA.