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Green ammonia is gaining momentum as a globally significant technology for deep decarbonisation. In this thesis, several models are developed across chemical, techno-economic, and energy system modelling disciplines to explore the future role of green ammonia. First, standalone models of production (i.e., power-to-ammonia) and re-electrification (i.e., ammonia-to-power) are developed and compared to competing technologies. Second, these models are integrated into a planning and dispatch energy system model (ESM) of India to 2050. The ESM has several novel additions including the sector coupling of hydrogen and ammonia, multiple years of granular weather data, and learning-curve-based technology cost forecasts. India is chosen as an ideal case study given its globally unmatched demand growth in all three relevant sectors: electricity, green hydrogen, and green ammonia. The projected electricity demands for green hydrogen and ammonia production account for 25% of the total Indian electricity demand in 2050, underscoring the transformational potential that green hydrogen and ammonia sector coupling can have on the Indian energy system. The results of the state-of-the-art ESM highlight synergistic effects of hydrogen and ammonia sector coupling with the power system. The least-cost system employs seasonal green ammonia production paired with up to 40 million tonnes (i.e., 200 TWh) of ammonia storage, as well as some re-electrification via gas turbines. Sector coupling reduces system curtailment, addresses challenges of long-duration storage, and improves system resilience to interannual weather variations. While India is a crucial case study from a global decarbonisation perspective, the methodology and findings are generally applicable, and it is the aim of this work to motivate and accelerate the wider research community into considering the potential impacts of green ammonia sector coupling on electricity grid design. Finally, this work highlights strategic technology development direction for ammonia producers and gas turbine manufacturers, as well as implications for policymakers.

A brisk building boom of hydropower mega-dams is underway from China to Brazil. Whether benefits of new dams will outweigh costs remains unresolved despite contentious debates. We investigate this question with the "outside view" or "reference class forecasting" based on literature on decision-making under uncertainty in psychology. We find overwhelming evidence that budgets are systematically biased below actual costs of large hydropower dams - excluding inflation, substantial debt servicing, environmental, and social costs. Using the largest and most reliable reference data of its kind and multilevel statistical techniques applied to large dams for the first time, we were successful in fitting parsimonious models to predict cost and schedule overruns. The outside view suggests that in most countries large hydropower dams will be too costly in absolute terms and take too long to build to deliver a positive risk-adjusted return unless suitable risk management measures outlined in this paper can be affordably provided. Policymakers, particularly in developing countries, are advised to prefer agile energy alternatives that can be built over shorter time horizons to energy megaprojects.

This paper explores to what extent moving towards the 30% GHG emission reductions by 2020 with respect to 1990 in the EU can be considered a transformative target. To do so, we first define the concept of transformative targets from a complex systems perspective and show a novel approach and original results using an extended application of the GEM-E3 model. Traditional macroeconomic models cannot easily handle key synergetic system effects derived from green growth and sustainability policies, and thus require additional features. We analyse the role of semi-endogenous growth driven by learning-by-doing and low-carbon investment expectations following a long-term transformative trajectory.

In a number of African countries, the trophy hunting of large felids is an important revenue generator for landholders, governments and in some cases communities. The hunting of large felids is especially profitable but they are sensitive to harvest, as the killing of prime-aged, dominant males can lead to infanticide and lowered reproductive success. In an attempt to limit the negative impacts of trophy hunting on large felids, the scientific community has proposed a number of interventions, including age restrictions on the animals that may be hunted. Such interventions are theoretically complementary to trophy hunting, as hunters typically seek large trophies, and older animals are normally larger than younger ones in large felids. If trophy size results in an increase in trophy price, then interventions that improve average trophy size could confer elevated earnings. This is particularly true if such interventions increased the number of failed hunts such that the same tag can be sold more than once. However, if trophy size is not one of the most important factors determining the desirability of a hunt (which we judge by the price paid for a trophy hunt package), it may be more difficult to implement such schemes. It is therefore important to evaluate potential determinants of trophy hunt package price; and we examine that here for leopards (Panthera pardus) in Africa, at both the country and outfitter level. We show that Tanzania and Botswana have the most expensive package prices while South Africa has the cheapest packages. At the country level, we found no statistical relationships between package price and leopard trophy size (either through advertised website or Safari Club International (SCI) leopard trophy size), country GDP, relative hunt success, or quota size. Contrastingly, the number of charismatic species offered within a package and an index of outfitter reputation (as measured by total SCI trophy records) were positively associated with package price. Interestingly, SCI leopard trophy size was inversely correlated with package price. Our results suggest that hunters do not value leopard trophy size above other factors, which could hinder the implementation of more sustainable, age-based leopard hunting regulations.

Despite the fundamental role given to the sustainability of intergenerational programming regarding their demonstrated impact on an aging society, only a few studies have undertaken an exploration of the qualitative core dimensions of sustainable intergenerational programs. This article addresses how the sustainability of educational intergenerational programs relates to why and how intergenerational program managers in the Portuguese area of Porto may have developed different attitudes and beliefs around adequate implementation of the programs. Drawing on qualitative interview data of a four-case fieldwork study conducted in Porto, Portugal, the study examines autonomy, empowerment, and intergenerational relationships as dimensions other than time duration behind program sustainability. Attention to the managers’ narratives on how intergenerational programs are implemented can help to explain why some dimensions are more highlighted than others. A qualitative analysis of intergenerational program sustainability, it is argued, offers considerable findings which provide opportunities to its implementation and intersection with managers’ beliefs. Findings suggest a need to de-emphasize both time duration and managers’ persona as the key for sustainability. We recommend intergenerational program sustainability as an area for future theorizing through providing a conceptualizing framework that might go beyond the normative focus on its duration and into the relational nature of these programs.

Environmental distribution conflicts (EDCs) related to the construction and operation of waste incinerators have become commonplace in China. This article presents a detailed case study of citizen opposition to an incinerator in the village of Panguanying, Hebei Province. Drawing on in-depth fieldwork, we show how this case was notable, because it transcended the local arena to raise bigger questions about environmental justice, particularly in relation to public participation in siting decisions, after villagers exposed fraudulent public consultation in the environmental impact assessment. An informal network between villagers and urban environmental activists formed, enabling the Panguanying case to exert influence far beyond the village locality. This network was critical in creating wider public debate about uneven power and substandard public participation in siting disputes, a central feature in many Chinese EDCs. By transcending local specificities and exposing broader, systemic inadequacies, this case became instrumental in supporting "strong sustainability".

Interdisciplinary energy research that focuses on the upcoming energy transition is growing at pace and scale given the goal of the Paris Agreement to limit global warming to 1.5 °C. As a consequence, integrated interventions are needed to support the energy transition. However, gaps in the energy literature remain on how to manage uncertainties inherent in energy transition. Based on a review that showcases some of the shortcomings in the current literature, this paper introduces a novel framework to provide a structure on how to engage with uncertainty called targeted and tangential effects. Relevant case studies in residential energy and energy justice as well as household retrofits and health are used to demonstrate how the targeted and tangential framework can be used. The targeted and tangential effect concept provides an innovative framework for energy researchers and practitioners to use to proactively recognize and identify uncertainty in the energy transition. Benefits and shortcomings of this framework are presented. Areas of future research are identified, including relevance for policy.