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Granular economic insights on the net-zero transition in electricity and industry
No full textMeeting ambitious decarbonisation targets will require significant emission reduction efforts from industries, particularly the power sector, which is responsible for more than 30% of global emissions. Yet, the challenge of how to design markets and policies within the power sector and industry overall so as to accelerate decarbonisation while ensuring the economic benefits, efficiency and balance of the multi-objectives in the transition (e.g., security of supply, decarbonisation and affordability) is a key question and one which remains unresolved. Through four novel research papers, this thesis explores this question by using interdisciplinary datasets and employing advanced modelling and econometric approaches. The first paper constructs a novel framework to investigate the nationwide economic value that renewable-based smart local energy systems (SLES) can create and applies the framework to Great Britain as a test case. The results highlight the significant economic value that SLES can create and emphasise the importance of their market design, regional participation, and system configuration. The second paper explores the idea of making resource adequacy (i.e., the ability of an electricity system to meet peak demand reliably with a given probability) a private good facilitated by smart technologies and grid digitalisation, and concludes that this new conceptualisation can improve cost-effectiveness and help accelerate the decarbonisation process. However, this raises questions related to energy equity. By building an advanced optimisation model for a hypothetical energy-only market counterfactual (i.e., a liberalised market where generators are only remunerated for the electricity they generate), the third paper provides a systematic empirical assessment of future challenges that must be addressed by policy instruments beyond the basic electricity market functions. Applying the model to 17 European countries, the results reveal significant 'missing money' challenges to achieve system adequacy and carbon neutrality, which are, in reality, usually facilitated by the capacity market and renewable subsidies. The results highlight the combined severity of the challenges and the importance of developing proper remuneration for investments, as well as fully accounting for market outcome dynamics in the modelling. Finally, the fourth paper investigates the role of macro-level (common) and industry-specific driving forces in emissions intensity reduction patterns through the application of a block-level dynamic factor model applied to new industry-level emission data. The results highlight the role of sector-specific drivers in decarbonisation and suggest that effective climate policy should balance broad incentives with targeted industry support. Overall, this thesis provides granular insights into opportunities and challenges within the power sector and associated industries, highlighting the importance of designing the right systems and market mechanisms as well as policies to incorporate new technologies and ensure economic benefits in the decarbonisation process
Intelligent interaction at scale
No full textMulti-Agent Reinforcement Learning (MARL) aims to develop intelligent agents capable of complex interaction and coordination, but faces significant challenges. Standard single-agent reinforcement learning (RL) algorithms cannot achieve stable, pro-social behaviour in general-sum games, where individual and collective interests may conflict. Simultaneously, scaling learning agents in handling numerous interacting external agents and increasing the internal complexity (parameter count) of individual deep RL agents presents significant challenges; unlike supervised learning, larger deep RL models often fail to yield improved performance.This thesis addresses these challenges through complementary algorithmic and architectural advances. First, focusing on inter-agent dynamics, we investigate Opponent Shaping (OS). We introduce Consistent Learning with Opponent-Learning Awareness to formally resolve inconsistencies in prior OS methods that inaccurately model co-player adaptation. We further develop Shaper, scaling OS effectively to high-dimensional games with long horizons and demonstrating the benefits of shaping in more complex settings. The open-source JaxMARL library is also presented as a tool to accelerate MARL research.Second, we explore Mixture-of-Experts (MoE) architectures within deep RL to address the challenge of internal agent complexity and scalability. We demonstrate that MoEs, particularly Soft MoEs, unlock parameter scaling in value-based deep RL. Performance increases with model size, mitigating issues like representational collapse observed in standard architectures. Evaluating MoEs under the amplified non-stationarity of multi-task and continual RL further highlights their capacity for robust learning and specialisation. To motivate future research and keep the multi-agent theme of this thesis, we draw parallels between managing internal expert coordination and external multi-agent challenges.These contributions advance scalable MARL by providing methods to manage inter-agent influence (OS) and intra-agent complexity (MoE) by improving consistency, scalability, and architectural effectiveness
AC field driven interactions in concentrated electrolytes
Get PDFUsing a surface force balance, we measure the force between two crossed-cylinder electrodes for different electrolyte systems and different geometrical configurations under the influence of an AC field. When an AC field is applied to concentrated mixtures of an ionic liquid (IL) in a polar solvent, a force arises that is at least an order of magnitude larger and slower to reach steady state than the static response of the electrolyte. We demonstrate that this AC field effect persists in concentrated electrolytes beyond what has already been observed in pure ILs or aqueous electrolytes. Furthermore, we show that the magnitude of the electric field force response is dependent on the electrode radius of curvature. In experiments with pure ILs, a stronger force magnitude is observed for a smaller radius of curvature, implying that these interactions can be fine-tuned through geometrical design. These observations should guide the application of AC electric fields for the control of colloids and the design of passive control mechanisms in microfluidics and nanotribology
Assessing the Effectiveness of the Ramsar Convention in the Conservation of Nesting Waterbirds in Benin, West Africa
Get PDFThe longest-standing international treaty for wetland and waterbird protection, the Ramsar Convention has resulted in the establishment of more than 2500 protected areas covering over 2.5 million square kilometers around the world. However, its measures are not legally binding, and its effectiveness as a tool for wildlife conservation has rarely been quantitatively assessed. In Benin, West Africa, breeding waterbirds are subjected to intense hunting and egg harvesting for both commercial and subsistence purposes. We quantified count data of waterbirds and eggs taken by local hunters and trappers to assess the effectiveness of the Ramsar Convention as a wildlife conservation tool in southeastern Benin. During the six-month period between May and October 2022, 64 people reported harvesting a total of 12,053 breeding waterbirds and 63,987 eggs, comprising eight species in three families in Ramsar site 1018. Birds most heavily targeted included Allen’s Gallinule (Porphyrio alleni), with 4187 breeding birds taken (~35% of all birds captured), and the White-faced Whistling Duck (Dendrocygna viduata), with 24,491 eggs taken (~38% of all eggs taken) over the course of a single breeding season. The Eurasian Moorhen (Gallinula chloropus) and Lesser Moorhen (Paragallinula angulata) were the third and fourth most targeted bird species, respectively, followed by the African Swamphen (Porphyrio madagascariensis), Black Crake (Zapornia flavirostra), African Jacana (Actophilornis africanus), and African Crake (Cecropsis egregia). Captured waterbirds were sold live at local markets, while eggs were eaten by hunters, except eggs containing chicks, which were discarded. Our findings show heavy persecution of waterbirds during their breeding season, when nesting birds are especially vulnerable to human predation, on a scale that is likely unprecedented and threatens to drive declines of targeted species in Benin. As local residents do not currently appear to recognize any deterrents to the uncontrolled hunting of breeding waterbirds or the collection of eggs in Ramsar site 1018, there is an urgent need to better leverage the Ramsar Convention to enforce conservation practices in this region
Sourcing Critical Metal from Critical Habitat: Is the Trade-Off Worth Making?
Get PDFThis study analyzes the environmental impact of nickel mining on biodiversity in Indonesia’s Wallacea region, using habitat quality as a proxy. It employs the Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) Habitat Quality Model to project current and future habitat quality and degradation. Findings confirm that nickel mining significantly threatens habitat quality. Under a future scenario, 10% (513 km2) of excellent-quality habitat is projected to be lost across the study area. Specifically, mining zones face severe degradation and a future absence of excellent habitat, though protected areas are expected to maintain excellent quality. The study highlights Indonesia’s core dilemma between economic nickel dominance and severe environmental destruction, stressing the need for equitable global risk-sharing. We recommend three strategies: (1) an Integrated Land-Sparing Strategy, (2) Responsible Mining Practices, and (3) Risk Mapping with Equitable Global Risk-Sharing Policies
Optimizing Interface Dielectric Loss in Superconducting Coplanar Waveguide Resonators for Improved Quantum Circuit Coherence
Get PDFSuperconducting quantum computing systems, including coplanar waveguide (CPW) resonators and qubits, are highly susceptible to energy dissipation from two-level systems (TLS) within bulk and interfacial dielectrics. CPW resonators serve as an ideal platform for characterizing these material losses at the single-photon excitation level. Building on recent experimental evidence that interface engineering can mitigate TLS losses, this study employs simulations to evaluate resonator quality factors across various interface modifications. Our results demonstrate that reducing losses at the substrate–air (SA) interface can increase the internal quality factor Qi by up to three orders of magnitude. While etching the SA interface also enhances Qi, material loss remains the dominant dissipation mechanism. Furthermore, we find that other lossy interfaces have a significantly smaller impact on the quality factor compared to the SA interface. These simulation results align with established experimental findings, providing a robust framework for refining resonator design. This work offers precise guidelines for TLS mitigation, essential for enhancing coherence times and developing more reliable superconducting quantum processors
Leptospirosis Incidence at Four Sites in Sub-Saharan Africa and South East Asia: An International Multi-Site Hybrid Surveillance Study
Get PDFBackground: There are few leptospirosis incidence studies despite such estimates being central to accurate burden of disease estimation. We used data from the multicenter Febrile Illness Evaluation in a Broad Range of Endemicities (FIEBRE) study to make leptospirosis incidence estimates from new sites. Methods: Febrile patients aged ≥2 months in Laos, Malawi, Mozambique, and Zimbabwe were enrolled and underwent standardized clinical and exposure assessment. Acute and convalescent sera were tested by Leptospira microscopic agglutination test and acute plasma by lfb1 polymerase chain reaction (PCR). Participants with ≥4-fold rise in antibody titer between acute and convalescent sample, or Leptospira PCR positive for the lfb1, had confirmed leptospirosis. Leptospirosis incidence was estimated after adjusting for incomplete enrollment of febrile patients, availability of paired sera, and use of study healthcare facilities by febrile patients based on healthcare utilization data from community controls. Results: Leptospirosis incidence (95% CI) per 100 000 population per year was 1302 (1011, 1677) in Laos, 1337 (874, 2044) in Malawi, 187 (85, 409) in Mozambique, and could not be calculated for Zimbabwe. Sensitivity analysis restricted to pre-COVID years of 2018 and 2019 produced similar estimates of incidence to that of the whole study period. Conclusions: Leptospirosis incidence was high at the Laos, Malawi, and Mozambique sites and at the upper end of published incidence estimates from the Asia and Africa regions. We recommend more leptospirosis incidence studies be done in areas lacking data to strengthen leptospirosis global burden of disease estimates and to stimulate progress on diagnosis, management, and control
Identifying community pharmacists’ preferences for attributes of public health interventions in Kenya: a discrete choice experiment
Get PDFCommunity pharmacies are increasingly recognized as access points for public health interventions (PHIs) such as vaccination, family planning services, and disease screening. In Kenya, evidence suggests the feasibility of pharmacy-delivered PHIs; however, the uptake remains inconsistent. This is partly attributed to poor programme design without taking pharmacy providers preferences into consideration. We employed a discrete choice experiment (DCE) to investigate community pharmacists’ preferences for attributes of PHIs delivered in community pharmacies in Kenya. We constructed a Bayesian efficient design and conducted a DCE survey among 663 community pharmacy providers in Makueni, Nairobi, and Kisumu counties in Kenya from January 2025 to March 2025. Panel multinomial mixed logit, generalized multinomial logit, and latent class models were used in the analysis. We also estimated willingness to pay (WTP) and willingness to accept (WTA) estimates using cost and profit margins as the monetary estimates, respectively. We found that community pharmacists were willing to offer PHIs with a low preference for opting out (β = −3.5723, P < 0.01). Preferences for PHIs significantly increased with higher profit margins (β = 0.028, P < 0.01) and decreased with higher cost of equipment (β = −0.00023, P < 0.01). There were higher preferences for PHIs that require moderate training (β = 0.266, P < 0.01) and extensive training (β = 0.141, P < 0.05) compared to no additional training and lower preferences for PHIs with complex interventions compared to simple interventions (β = −0.323, P < 0.01). The WTP estimates showed that providers were willing to pay Khs. 11 738 (USD 90) for moderate training and Kshs. 7327 (USD 56) for extensive training. Moreover, the WTA estimates showed that providers were willing to accept a 10.9% increase in profit margin in order to deliver complex interventions. In addition to this, a three-class latent class model revealed preference heterogeneity among the respondents. These findings can be used to inform the design of PHIs to enhance uptake and acceptability among providers
Visible‐Shortwave Infrared (VSWIR) Spectral Parameters for the Lunar Trailblazer High‐Resolution Volatiles and Minerals Moon Mapper (HVM 3 )
Get PDFPlain Language Summary: The High‐resolution Volatiles and Minerals Moon Mapper (HVM3) is one of two science instruments on the Lunar Trailblazer smallsat mission, whose science goal is to understand the distribution, abundance, and form of water on the Moon, as well as the lunar water cycle. HVM3 uses patterns in infrared light reflection and absorption at different wavelengths to detect water and minerals in rocks and soils on the Moon's surface. In July 2025 the Lunar Trailblazer mission end was declared. Here, we detail the formulation and testing of algorithms for making water and mineral maps in preparation for the anticipated HVM3 returned data using existing Moon Mineralogy Mapper (M3) and Deep Impact spacecraft lunar data sets, which are similar types of instruments. We demonstrate that presented spectral parameters can distinguish lunar minerals of interest and therefore, capture lunar mineral diversity well. We also show that a newly developed water spectral parameter can be used as a reliable indication of lunar surface water presence, thereby demonstrating the value of expected HVM3 maps for the broader scientific community as well as planning future exploration of the Moon