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Carbon capture and storage in the UK: Deployment requirements and risks
Get PDFThe UK’s pathway to Net Zero by 2050 is critically dependent on the large-scale deployment of carbon capture and storage (CCS) technologies. Despite strong political commitments and significant funding pledges, no operational CCS facilities currently exist in the UK, and global experience shows high project failure rates. This raises the central question: can CCS be deployed at sufficient scale and pace to meet national climate targets?
This report evaluates current UK CCS plans against the Climate Change Committee’s (CCC) projections of required capacity, using project pipeline and historical failure rate data, and extrapolates planned capacity growth to 2050 under varying assumptions of project success and failure.
Results show that while planned projects could deliver 5–10 MtCO₂ annually by 2030, this falls short of the CCC’s requirement of 13 MtCO₂. Even under optimistic assumptions, deployment would require compound annual growth rates of up to 75% in early years. Historical failure rates of 82% suggest that without significant improvements, UK CCS capacity could reach only one-third of required levels by 2050.
The report recommends sustained political and financial support, the prioritisation of CCS in sectors without viable alternatives, integration of Carbon Removal Obligations into regulation, and flexible industrial cluster decarbonisation strategies. Public acceptance and ethical governance are also essential to ensure CCS complements, rather than displaces, near-term emissions reductions, mitigating risks of mitigation deterrence and stranded assets
Purposive transition governance for road freight decarbonization
Get PDFRoad freight decarbonization, like other complex system transitions, presents a formidable political, social and organizational as well as technical and economic challenge. While technical and economic aspects have received considerable research focus, there is much less research on political, social and organizational aspects. Purposive road freight decarbonization furthermore needs an effective governance framework to coordinate system-level decision-making that reflects all these important system dimensions. Findings from literature regarding governance requirements for purposive system transitions are synthesized to form a novel framework organized around the three pillars of governance processes, effectiveness and legitimacy. This framework is validated and further developed via thirteen semi-structured interviews and a workshop with transport authorities and industry associations. Conclusions are drawn regarding maintaining system functions and managing asymmetric power relations during transitions; key governance enablers; and the importance of achieving input, throughput and output legitimacy. Governance connections are identified, and the implications of these for transition wickedness discussed
Oxidation of Gasoline Direct Injection Engine Soot in Oxygen-Lean and Oxygen-Rich Atmospheres: A Comparative Analysis of Physicochemical Properties
Get PDFGenuine Multipartite Entanglement is Not Necessary for Standard Device-Independent Conference Key Agreement
Get PDFConference key agreement aims to establish shared, private randomness among many separated parties in a network. Device-independent conference key agreement (DICKA) is a variant in which the source and the measurement devices used by each party need not be trusted. So far, DICKA protocols largely fall into two categories: those that rely on violating a joint Bell inequality using genuinely multipartite entangled states and those that concatenate many bipartite protocols. The question of whether a hybrid protocol exists, where a multipartite Bell inequality can be violated using only bipartite entanglement, was asked by Grasselli et al. [Quantum 7, 980 (2023)]. We answer this question affirmatively, by constructing an asymptotically secure DICKA protocol achieving the same rate as the concatenation of bipartite device-independent quantum key distribution, yet relying on a single joint Bell violation. Our results prompt further discussion on the benefits of multipartite entanglement for DICKA over its bipartite alternative, and we give an overview of different arguments for near-term devices
STEM Undergraduates’ Perceptions of AI Chatbots: A Cross-Sectional Descriptive Survey
Get PDFWe surveyed 297 STEM undergraduates at a single English-medium Sino–UK joint institution to document perceptions of AI chatbots for learning. Students reported high willingness to adopt AI chatbots (78%; 95% CI: 73.1–82.4) alongside concerns about over-reliance (67%; 95% CI: 61.4–72.1), content quality (52%; 95% CI: 46.2–57.5), and reduced human interaction (42%; 95% CI: 36.5–47.8). Over half (52%; 95% CI: 46.3–57.7) requested language/terminology support features, whereas only 16.8% reported language-related barriers. We attempted exploratory factor analysis and k-means clustering, but neither met the inclusion criteria; therefore, we report item-level frequencies only. The findings are descriptive and not generalisable (53% first-year, 80% male convenience sample). These patterns generate testable hypotheses about verification scaffolds, language support utility, and human–AI balance that warrant investigation through controlled studies
The importance of whole system considerations for sustainable, long-term CO₂ injection and storage: Interplay between infrastructure-related corrosion and reservoir rock chemistry effects on the evolution of the CO₂ storage capacity
Get PDFAs global emissions fail to reduce rapidly, Carbon Capture and Storage (CCS) is attracting ever-growing attention. CCS involves capturing, treating, transporting and storing CO₂ to ensure its long-term removal from the atmosphere. To design a viable CCS system, the different interactions and impacts of injected CO₂ (either as sub-critical or supercritical fluid) across the whole CCS system need to be considered. However, it is unclear how changes in fluid chemistry and the pre-existing reservoir rock chemistry influence the evolution of the two key storage properties, porosity and permeability.
This study investigates how upstream corrosion-induced fluid chemistry changes and realistic rock composition could affect the injectivity and storage capacity of reservoirs. The condition and material chosen for this project fall into the possible envelope of conditions of interest during CO₂ injection and storage. Corrosion occurring during CO₂ injection through saline aquifers was simulated at 40 bar, 60°C for two weeks, using X65 carbon and ¹³Cr steel. The fluid resulting from the experimental fluid-metal interaction was then reacted at ∼40 bar, 60°C for another two weeks with two fine-grained arkoses, with and without lithic clast, representative of siliciclastic reservoir rocks.
Results show that upstream corrosion caused a change in fluid chemistry and decreased fluid acidity. The corrosion-induced chemical changes had a marked effect on the evolution of porosity and permeability within the reservoir rocks. The storage capacity of reservoir rocks with diverse mineralogy is highly dynamic, and directly affected by rock chemical composition and, importantly, the chemical evolution of the incoming fluid
Consumption of commercial and traditional sugar-sweetened beverages among adolescents in Pakistan:evidence from a national survey
Get PDFBackground: Pakistan faces a growing burden of adolescent overweight, early-onset diabetes, and one of the world’s highest adult diabetes prevalence rates. Yet, nationally representative data on adolescents’ sugar-sweetened beverages (SSBs) consumption are lacking. This study addresses this evidence gap by examining consumption patterns and sociodemographic determinants of SSB intake, including both commercial (packaged) and traditional (home-prepared) drinks, among 10–16-year-olds in Pakistan. Methods: We analysed data from the nationally representative TAP (Tobacco & Adolescent Health in Pakistan) survey, conducted from December 2023 to May 2024, including 14,232 adolescents (63% in-school, 37% out-of-school) from nine districts. Weekly frequency of two SSB categories (‘commercial’ (packaged) including soft drinks, fruit drinks, energy drinks; and ‘traditional’ including traditional sweetened home-prepared beverages) was assessed. Consumption was categorised as low, moderate, or high. Weighted descriptive statistics and proportional/generalised ordinal logistic regression were used to examine associations with sociodemographic variables. Results: Overall, 70.5% of adolescents reported high total SSB intake (>7 times per week). High consumption was reported in 22.3% for commercial SSBs and 38.1% for traditional SSBs. In adjusted models, males (OR = 1.32, 95% CI: 1.16–1.51), older adolescents (OR = 1.39, 95% CI: 1.20–1.61), and out-of-school youth (OR = 1.48, 95% CI: 1.26–1.74) had greater odds of high total intake, while higher female caregiver’s education was protective (OR = 0.68, 95% CI: 0.54–0.86). Patterns for commercial SSBs were broadly similar, though male caregiver’s education was positively associated. Traditional SSBs also followed these trends, with stronger associations for out-of-school adolescents (OR = 2.05, 95% CI: 1.77–2.37) and rural residence (OR = 1.14, 95% CI: 1.01–1.28). Conclusion: SSB consumption including both commercial and traditional beverages is widespread among adolescents in Pakistan. Intake patterns vary significantly by sex, schooling, caregiver education and urbanicity. Policies should prioritise both school and community interventions, implement fiscal and labelling policies, and engage caregivers. Future research should assess portion sizes, nutrient profiles, and strategies to shift social norms around sugar use in beverages
A dandelion optimization-based MPPT control technique for solar PV system under partial shading conditions
Get PDFSolar photovoltaic (PV) systems require maximum power point tracking (MPPT) algorithms to ensure efficient energy harvesting. However, their performance deteriorates under partial shading conditions (PSC) due to non-uniform irradiance, temperature fluctuations, and other environmental factors. This paper proposes a novel MPPT method based on the Dandelion Optimization (DO) algorithm—a nature-inspired metaheuristic technique—designed to accurately identify the global maximum power point (GMPP) under PSC. The proposed DO-MPPT algorithm is evaluated through simulations under various shading scenarios and compared against four established algorithms: Perturb and Observe (P&O), Particle Swarm Optimization (PSO), Dragonfly Algorithm (DFO), and Adaptive Cuckoo Search (ACS). Results show that the DO algorithm achieves a convergence time of 0.2 s, a settling time of 0.23 s, and a tracking efficiency of 99.9 %, surpassing the alternatives in speed, accuracy, and stability. Furthermore, it minimizes voltage oscillations and reliably tracks GMPP across diverse operating conditions. These findings demonstrate the effectiveness of the DO algorithm in enhancing PV system performance under challenging real-world environments
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