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In recent decades, many societal changes have unfolded, including population ageing, reconfigurations of household structures, labour market transformation, and a secular deceleration of economic growth. These shifts pose considerable challenges to preexisting welfare states, particularly to the efficacy of countries’ pension systems. This dissertation examines the context and trajectory of pension reforms in Mexico, the United Kingdom, and the United States. Its contribution is to ascertain the viability and political feasibility of reforms that enhance the financial sustainability of their pension systems, while maintaining adequate income and coverage levels. The dissertation builds on political economy approaches and on the institutionalist literature, which highlight how the role of interest groups and structure of institutions and political systems shape policy outcomes. The frameworks of blame avoidance and credit-claiming are also considered, to provide a comprehensive analysis of the complex dynamics surrounding pension systems and reform efforts. This dissertation uses a mixed-methods approach – including public opinion surveys of 3,000+ individuals, semi-structured elite interviews, historical document analyses, and specialized fiscal and actuarial projections of selected pension reforms in the three selected countries. It addresses three core research questions: 1) What is the current context for pension reform in Mexico, the United Kingdom, and the United States given their histories? 2) Is the necessary (for achieving specific minimum levels of sustainability, adequacy, and coverage) pension reform politically feasible? 3) How do the characteristics of each reform affect its political feasibility? Corollary: The modification of which channel (benefits, contributions, retirement age) is perceived as more politically feasible for diverse stakeholders? The methodology chosen provides a timely picture of the context surrounding potential pension reforms in the three case studies. In Mexico, credit-claiming and the interests of private stakeholders explain the success of recent pension reforms, and partisan politics are the key determinants for future fiscal changes. For the United Kingdom, the institutionalist literature helps explain the reasons for the relatively easier reform avenues; the most politically feasible reforms are those in the private sector, while the housing market is of key importance for pensions. In the United States, the institutionalist literature and the framework of blame avoidance also help explain the current legislative gridlock and the reasons why no major reform has been enacted for decades. For Mexico and the United Kingdom there exist politically feasible reforms, notably a modification of the retirement age channel, that can increase the system’s sustainability while maintaining income adequacy and coverage; whereas based on the current context of extreme polarisation and legislative gridlock, there do not seem to exist politically feasible pension reforms that preserve the structure of Social Security in the United States. The dissertation brings the lens of political feasibility to bear on a previously technical literature on the structure of the pension systems in the three countries, and thus on the feasibility of reform to deliver financial sustainability, adequacy of retirement incomes, and adequate coverage of the old age population. It identifies the feasible routes for reform in Mexico and the United Kingdom, but concludes that the political economy context the United States has reached rules out feasible reforms of its current pension structures.

The aggravating global problems of energy crisis, rising atmospheric greenhouse gas concentrations and accumulation of persistent waste have attracted the attention of scientists, policy-makers and global organisations to come up with effective and expeditious solutions to address these challenges. In this context, the development of sustainable technologies driven by renewable energy sources for the production of clean fuels and commodity chemicals from diverse waste feedstocks is an appealing approach towards creating a circular economy. Over the years, semiconductor photocatalysts based on TiO₂, CdS, carbon-nitrides (CNx) and carbon dots (CDs) have been widely used for the photocatalytic reforming (PC reforming) of pre-treated waste substrates to organic products, accompanied with clean hydrogen (H₂) generation. However, these conventional solar-driven processes suffer from major drawbacks such as low production rates, poor product selectivity, CO₂ release, challenging process and catalyst optimisation, and harsh waste pre-treatment conditions, which limit their commercial applicability. These challenges are tackled in this thesis with the introduction of new and efficient photoelectrochemical (PEC) and chemoenzymatic processes for reforming a diverse range of waste feedstocks to sustainable fuels. Solar-driven PEC reforming based on halide perovskite light-absorber is first developed as an attractive alternative to PC reforming. The PEC systems consist of a perovskite|Pt photocathode for clean H₂ production and a Cu-Pd alloy anode for reforming diverse waste streams, including pre-treated cellulosic biomass, polyethylene terephthalate (PET) plastics, and industrial by-product glycerol into industrially-relevant, value-added chemicals (gluconic acid, glycolic acid and glyceric acid) without any externally applied bias or voltage. Additionally, the single light-absorber PEC systems can also convert the airborne waste stream and greenhouse gas CO₂ to diverse products with the simultaneous reforming of PET plastics with no applied voltage. The perovskite-based photocathode enables the integration of different CO₂ reduction catalysts such as a molecular cobalt porphyrin, a Cu-In alloy and formate dehydrogenase enzyme, which produce CO, syngas and formate, respectively. The versatile PEC systems, which can be assembled in either a ‘two-compartment’ or standalone ‘artificial leaf’ configurations achieve 60‒90% oxidation product selectivity (with no over-oxidation) and >100 µmol cm‾² h‾¹ product formation rates, corresponding to 10²‒10⁴ times higher activity than conventional PC reforming systems. In addition to developing PEC platforms, this thesis also explores avenues for circumventing the harsh alkaline pre-treatment strategies (pH >13, 60‒80 ºC) adopted for photoreforming waste substrates. For this purpose, a chemoenzymatic pathway is introduced whereby PET and polycaprolactone plastics were deconstructed using functional enzymes under benign conditions (pH 6‒8, 37‒65 ºC), followed by PC reforming using Pt loaded TiO₂ (TiO₂|Pt) or Ni₂P loaded carbon-nitride (CNx|Ni₂P) photocatalysts. The chemoenzymatic reforming process demonstrates versatility in upcycling polyester films and nanoplastics for H₂ production at high yields reaching ∼10³‒10⁴ µmol gsub‾¹ and activities at >500 µmol gcat‾¹ h‾¹. The utilisation of enzyme pre-treated plastics also allowed the coupling of plastic reforming with photocatalytic CO₂-to-syngas conversion using a phosphonated cobalt bis(terpyridine) co-catalyst immobilised on TiO₂ (TiO₂|CotpyP). Finally, moving beyond solar-driven systems, a bio-electrocatalytic flow process is demonstrated for the conversion of microbe pre-treated food waste to ethylene (an important feedstock in the chemical industry) on graphitic carbon electrodes via succinic acid as the central intermediate. In conclusion, with its focus on improving efficiencies, achieving selective product formation, building versatile platforms, diversifying substrate and product scope, and reducing carbon footprint and economic strain, this thesis aims to bring sustainable waste-to-fuel technologies a step closer to commercial implementation.

Abstract While it is generally accepted that our fossil fuel-dominated energy systems must undergo a sustainable transition, researchers have often neglected the potential impacts of this on water and land systems. However, if unintended environmental impacts from this process are to be avoided, understanding its implications for land use and water demand is of crucial importance. Moreover, developed countries may induce environmental stress beyond their own borders, for instance through extensive imports of bioenergy. In this paper, Germany serves as an example of a developed country with ambitious energy transformation targets. Results show that in particular, the politically-driven aspiration for more organic farming in Germany results in a higher import quota of biomass, especially biofuels. These imports translate into land demand, which will exceed the area available in Germany for bioenergy by a factor of 3–6.5 by 2050. As this will likely bring about land stress in the respective exporting countries, this effect of the German energy transformation ought to be limited as much as possible. In contrast, domestic water demand for the German energy system is expected to decrease by over 80% through 2050 due to declining numbers of fossil-fuelled power plants. However, possible future irrigation needs for bioenergy may reduce or even counterbalance this decreasing effect. In addition, energy policy targets specific to the transport sector show a high sensitivity to biomass imports. In particular, the sector-specific target for greenhouse gas reductions will seemingly promote biomass imports, leading to the above-described challenges in the pursuit of sustainability.

Moisture availability is a strong determinant of decomposition rates in forests worldwide. Climate models suggest that many terrestrial ecosystems are at risk from future droughts, suggesting moisture limiting conditions will develop across a range of forests worldwide. The impacts of increasing drought conditions on forest carbon (C) fluxes due to shifts in organic matter decay rates may be poorly characterised due to limited experimental research. To appraise this question, we conducted a meta-analysis of forest drought experiment studies worldwide, examining spatial limits, knowledge gaps and potential biases. To identify limits to experimental knowledge, we projected the global distribution of forest drought experiments against spatially modelled estimates of (i) future precipitation change, (ii) ecosystem total above-ground C and (iii) soil C storage. Our assessment, involving 115 individual experimental study locations, found a mismatch between the distribution of forest drought experiments and regions with higher levels of future drought risk and C storage, such as Central America, Amazonia, the Atlantic Forest of Brazil, equatorial Africa and Indonesia. Decomposition rate responses in litter and soil were also relatively under-studied, with only 30 experiments specifically examining the potential experimental impacts of drought on C fluxes from soil or litter. We propose new approaches for engaging experimentally with forest drought research, utilising standardised protocols to appraise the impacts of drought on the C cycle, while targeting the most vulnerable and relevant forests.

Ammonia has been responsible for feeding population growth in the 20th century through synthetic fertilizer, and is poised to become the preferred energy storage medium for a society powered by renewable electricity in the 21st century. However, conventional brown ammonia production through the Haber-Bosch process is optimized for utilization of centralized and steady energy supply from fossil-fuels. When shifting to distributed and intermittent energy supply through wind and solar energy, a re-optimization is required for a low-capital and flexible green ammonia production processes. This thesis re-designs and Haber-Bosch process by targeting the integration of reaction and separation in a single process vessel at low pressures, thereby achieving the simplification and down-scaling of the high pressure recycle loop of the Haber-Bosch process. Materials are developed for this purpose, the feasibility of integration is demonstrated, and mathematical modeling is utilized for assessing the application of the single-vessel process to a range of renewable energy sources in comparison to competing ammonia production processes. Herein, a catalyst with low-temperature (< 350°C) and high-conversion (i.e. near equilibrium) activity is developed using ruthenium nanoparticles as the active metal supported on ceria and promoted with cesium to mitigate hydrogen and ammonia inhibition, respectively. This catalyst is compared to commercial iron-based catalyst from the perspective of the final application. Concurrently, a high-temperature (> 300°C) manganese chloride absorbent is developed that resists decomposition and is stable when supported on silica. These catalyst and absorbent are integrated in a layered reactor configuration to demonstrate the feasibility of the integrated process by exceeding single-pass reaction equilibrium. Mathematical modelling of ammonia production processes illustrates that at small-scales (< 1 t day-1) the single-vessel process is optimal compared to the Haber-Bosch process due to its modular design. In addition, it can achieve simpler ramping because the Haber-Bosch process is constrained by heat-integration in the recycle loop and the potential for runaway reaction. For final application, the pairing of ammonia production processes with examples of intermittent solar and wind sources demonstrates that the flexibility of the production process is essential when considering non-ideal sources of energy with a long-term (e.g. seasonal) oscillations. Flexible ammonia production also expands the economic usage of ammonia as an energy storage vector from the seasonal to the weekly time-scale, with advantage compared to batteries or hydrogen. The work of this thesis provides a framework for advancing the electrification of the chemical industry given the novel constrains of intermittent and distributed renewable energy. A systems level approach is applied from the ground up, starting from material design and progressing to optimized process design and application.

This chapter explores the implications of trade unions not being formally involved in local service improvements in the NHS (England) over the last decade. This is despite their involvement in the largest pay modernisation in the NHS (Buchan and Evans 2007) and national level collective bargaining (Bach and Kessler 2012). This chapter draws on evidence from three national government-funded initiatives to illustrate the crowding out of collective dialogue, and concludes that such actions undermine the sustainability of service improvements and increase the potential for ‘partial failure’ (Hyman 1987, p. 30). This highlights the contradictory nature of management more generally in accepting the co-ordinating role of trade unions while eschewing the perceived critique of managerial objectives from which it could ultimately benefit.

Abstract Urban transformation is vital to global sustainable development as humans increasingly come to dwell in cities. Within cities, the mobility sector promises the highest potential of carbon emission reduction. The disruptive business innovation brought about by the advent of app-based smart-sharing systems is emancipating collaborative consumption of mobility at larger and deeper scales, ranging from car-pooling, expanded electric vehicle (EV) use to bike-sharing. Synchronizing the existing yet under-realized low-carbon transport modes in cities, such as public transport, with emerging and diversifying app-based sharing mobility business models, offers huge potential to transform urban mobility toward sustainability. Yet, the rapid business expansion and innovation of the sharing mobility companies have profoundly challenged existing socio-economic relationships, knowledge systems and physical infrastructures in cities. This study explores the synergy between the social-ecological innovation in the sharing economy and the sustainable development of urban systems, using empirical data from three business cases in the emerging sharing mobility sector – in modes of ride-sharing, EV-sharing and bike-sharing - of Shanghai, China. It indicates that there is a strong co-evolution mechanism between the transformation towards more sustainable city at the macro-level and the business ecosystem innovation towards greener and smarter transport at the meso-level. We argue that the two level transformations, triggered by the disruptive innovation of the sharing economy and led by urban transformation towards sustainability, mutually influence each other and re-enforce sustainable values and practices in the fast changing urban context and business innovations in Shanghai.

Abstract Level(s) is a common European Union framework of core sustainability indicators for measuring the performance of buildings along their life cycle, enabling emissions reductions and circular resource flows. A fundamental tool for the development of European policies to boost the market for sustainable, resilient and climate change adapted buildings. The objective of this study is to contribute to the existing body of knowledge in the field of sustainable building research, through the definition of strategies to adopt Level(s) for bringing buildings into the Circular Economy. For this reason, a triple SWOT-Analytical Hierarchy Process (AHP)-TOWS analysis was applied. The strengths, weaknesses, opportunities and threats (SWOT) of the Level(s) have been identified in relation to the availability of resources, product quality, internal and market structure, consumer perception, among others. The results obtained are conclusive in terms of the experts’ positive assessment of the tool; highlighting factors such as its response to the need to adapt buildings to climate change, its a standard reference language, and its use in multiple situations. However, several barriers have also been identified, which may affect its development, including its complexity of use, its lack of self-sufficiency, and its dependence the criteria used in each evaluation. Finally, the key strategies to be carried out for the implementation of the Levels have been established.