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Optimising residential electricity demands through innovative demand side management strategies in Nigeria
No full textMirzania, Pegah - Associate Supervisor
Hart, Phil - Associate SupervisorThe Nigerian power supply faces significant shortages, resulting in frequent nationwide power
outages, load shedding and severe energy crises. The country relies heavily on a centralised
energy mix, primarily comprising gas-fired power plants with a capacity of 10.6 Giga Watt
(GW) and hydropower with a capacity of 1.9 GW. Despite having a total installed capacity of
12.5 GW, only around 4 GW actually reaches end consumers. This is mainly due to limited
transmission infrastructure, inadequate distribution facilities, poor metering, inadequate fuel
supply, lack of market competition and inadequate management of energy resources.
Innovative demand side management (DSM) strategies are required to optimise electricity
demands at customer ends to improve the power supply in Nigeria.
This thesis develops an innovative DSM method of utilising direct load control (DLC), acting
as a mandatory operational strategy for regional residential grids, as opposed to traditional
approach of load shedding. The proposed DLC method controls residential loads by classifying
loads into three different categories: critical, less critical, and non-critical. The evaluating
metrics include energy cost savings and comfort levels of residence (i.e., the length of supply
of the critical loads). Furthermore, paper-based surveys are used as the quantitative methods to
evaluate the understanding, awareness, and attitude of Nigerian households towards DSM
under different representative groups. The survey data are also used to model load profiles, to
which the DLC is applied to validate the proposed DLC method.
The proposed DLC method was compared with load shedding considering three load shedding
scenarios: 1) nobody uses generators during power cut period, 2) running home generators for
4 hours per day during power cut period, and 3) running home generators for 8 hours per day
during power cut period. Simulation results showed that, for scenario 1, the proposed DLC
method results in a 20% of energy cost saving and a 28% improvement of in comfort level; for
scenario 2, the proposed DLC method results in an 87% decrease in household expenditure and
a 5% decrease in comfort level, and for scenario 3, the proposed DLC method results in a 93%
energy cost saving but a 39% decrease in comfort level.
The study shows that households with the post-paid billing systems are less responsive to the
DSM approach. However, the proposed DLC strategy results in higher cost savings on the post-
paid billing systems (23%) than the pre-paid billing systems (17%), both compared to the load
shedding approach. Households working in the public sector who use the pre-paid billing
system have proven to be the most effective target group for implementing DSM. This is
because these households consume 23% more energy on average compared to other
representative household groups. This research presents an innovative DLC method designed
to enhance power supply in residential grids, providing an alternative to load shedding in
developing countries. Additionally, it utilises a methodology that involves gathering data
through paper-based surveys to construct electricity demand profiles, establishing a numerical
dataset for future DSM studies. The research findings reveal that the proposed DLC method
not only lowers energy expenses but also improve overall household comfort and quality of
life.PhD in Energy and Powe
Single- and two-stage fan designs for a supersonic airliner with focus on certification noise reduction
Get PDFA comprehensive analytical approach is taken to compare the aerodynamic performance as well as the landing and take-off noise of a single and a two-stage fan at pre-design level. The fans were designed for the engines of a supersonic airliner with the goal of minimizing noise certification levels. The prediction of aerodynamic performance is performed for on- and off-design points using analytical and semi-empirical models, the noise for landing and take-off operations is calculated using analytical approaches in modelling noise sources and propagation to the certification points. Certification metrics are also calculated and used in this comparison. This process is run for both fan designs on a baseline take-off trajectory in accordance with current regulations, as well as an optimized trajectory exploiting potential regulation changes for supersonic aircraft. With this study, the authors are able to demonstrate that a two-stage fan design produces significantly lower noise levels. In configurations and on trajectories on which fan noise is dominant, significantly lower certification levels could be achieved.The authors thank the European Union for the financial support in the context of the Horizon 2020 Research and Innovation Programme (Project SENECA, Grant Agreement No. 101006742).AIAA SCITECH 2025 Foru
Partitioning and removal of per- and polyfluoroalkyl substances (PFAS) in full-scale surface flow treatment wetlands with different upstream wastewater treatment
Get PDFThe performance of treatment wetlands (TWs), as a nature-based solution, in mitigating persistent per- and polyfluoroalkyl substances (PFAS) and their interactions with existing treatment flowsheets remain unclear. This study investigated PFAS removal in two full-scale surface flow TWs treating secondary effluent from different domestic wastewater treatment plants (WWTPs). The systems demonstrated their capacities to safeguard natural water bodies by achieving discharge levels of the legacy PFOS (4–4.6 ng L−1) and PFOA (1.79–3.27 ng L−1) with removal efficiencies of 29%–38% and 15%–34%, respectively. Further upstream and downstream water quality monitoring in receiving waters is required to accurately evaluate PFAS contributions from WWTP effluents. Partitioning behaviour analysis revealed that sediment adsorption was the dominant removal pathway, achieving removal rates 16–61 times higher than plant uptake for PFOS and 1.8–6 times higher for PFOA. Sediment iron content, depth, and bulk density were positively correlated with PFAS sequestration, highlighting their importance in controlling PFAS mobility. PFOS accumulation in the sediment was greater in the TW for the WWTP dosing with ferric sulphate than the WWTP without chemical dosing (2.80 mg m−2 y−1 vs. 1.34 mg m−2 y−1). Notably, a conventional mass balance analysis was challenged by the transformation of PFAS precursors into terminal compounds, including PFOS and PFOA, potentially inflating input concentrations and contributing to mass imbalance during treatment. Further research is necessary to address these complexities, but the findings are encouraging for the use of TWs as scalable, eco-friendly solutions for mitigating PFAS pollution and are instructive for optimising wetland design and operation to safeguard aquatic ecosystems.National Institute for Basic Biology, Engineering and Physical Sciences Research Council, European Commission, Biotechnology and Biological Sciences Research CouncilThis research is gratefully supported by the project sponsor Anglian Water. C.S. gratefully acknowledges MUR and EU-FSE for financial support of the PhD fellowship PON Research and Innovation 2014-2020 (D.M 1061/2021) XXXVII Cycle in Chemical Sciences: “Green deal and Zero Pollution strategy: innovative solutions for emerging contaminants removal”. We also acknowledge support from the PFAS working group in BBSRC/EPSRC Environmental Biotechnology Network (EBNet) NIBB (BB/S009795/1).Journal of Water Process Engineerin
A core-shell thermal barrier coating with strong resistance to molten silicate attack and fracture
Get PDFWe report a new thermal barrier coating (TBC) with strong resistance to calcia–magnesia–alumina–silicate (CMAS) attack and fracture. The design is based on a core-shell microstructure where each building block of the TBC comprises a tough yttria stabilised zirconia (YSZ) core and a CMAS-resistant shell. To demonstrate the feasibility of the design, we select alumina, an established CMAS-resistant ceramic, as the shell material and manufacture core-shell TBCs by first synthesising “YSZ core-alumina shell” powder using the sol-gel method and then thermally spraying the powder to form core-shell TBCs. Microstructural characterisations confirm that a core-shell coating structure is successfully manufactured. However, the melting and mixing of alumina and YSZ in thermal spray result in the formation of a microstructure composed of alumina-alloyed zirconia grains and intergranular alumina, with the overall alumina concentration increasing from the core to the shell. The CMAS penetration depth through the core-shell TBC is over an order of magnitude lower than that through the benchmark YSZ TBC, which is attributed to the multiscale protection of the core-shell microstructure against CMAS infiltration through cracks and grain boundaries. The core-shell TBC has a similar stiffness to the YSZ TBC but exhibits a lower erosion rate and higher fracture toughness, indicating enhanced fracture resistance without compromising strain tolerance. The improved fracture resistance of the core-shell TBC is attributed to its less defective intersplat structure and greater ferroelastic toughening strain. Compared to the YSZ TBC, the core-shell TBC shows lower stiffness and nearly identical fracture toughness after annealing.Ying Chen would like to thank the funding support from Innovate UK (project number: 10040292) and the Henry Royce Institute for advanced materials through the Industrial Collaboration Programme (EP/X527257/1). Part of this work was supported by the new lecturer start-up grant awarded to Ying Chen by the Department of Materials at the University of Manchester. Ping Xiao acknowledges support from the Royal Academy of Engineering and Rolls-Royce for the appointment of Rolls-Royce/Royal Academy of Engineering Research Chair in Advanced Coating Technology. This work was supported by the Henry Royce Institute for Advanced Materials through the Researcher and Student Access Scheme, funded through EPSRC grants EP/R00661X/1, EP/S019367/1, EP/P025021/1 and EP/P025498/1. The authors would like to acknowledge the support of Mr Arturo Vara Herrera (Cranfield University) in the erosion experiments.Acta Materiali
The persistence of failure in water, sanitation and hygiene programming: a qualitative study
Get PDFIntroduction
Unsafe water, sanitation and hygiene (WASH) causes millions of deaths and disability-adjusted life-years annually. Despite global progress towards universal WASH, much of WASH programming continues to fail to improve health outcomes or be sustainable in the longer term, consistently falling short of internal performance indicators and sometimes negatively impacting the well-being of local stakeholders. Although sector experts in high-income countries have often provided explanations for such failures, the opinions of those implementing WASH programming at the ground level are rarely published.
Methods
In 2020, we purposively recruited 108 front-line WASH professionals in Malawi, South Africa, Tanzania and Zimbabwe to participate in 96 in-depth interviews, explaining why they believe WASH failure persists. Through participatory analysis, including framework analysis with additional axial coding and member-checking of our findings, we determined the core reasons for WASH failure as perceived by participants.
Results
Interviewees reported poor engagement and commitment of intended users, unrealistic and idealistic expectations held by funders and implementers, and a general lack of workforce and financial capacity as significant contributors to WASH failure. Our analysis shows that these issues stem from WASH programming being implemented as time and budget-constrained projects. This projectisation has led to reduced accountability of funders and implementers to intended users and a focus on measuring inputs and outputs rather than outcomes and impacts. It has also placed high expectations on intended users to sustain WASH services and behaviour change after projects officially end.
Conclusions
Our findings imply that WASH programming needs to move away from projectisation towards long-term investments with associated accountability to local governments and longitudinal measurements of WASH access, as well as realistic considerations of the needs, abilities and priorities of intended users. Funders need to reconsider the status quo and how adjusting their systems could support sustainable WASH services.Funding for this project was awarded by the Royal Academy of Engineering as part of the UK Government’s Global Challenges Research Fund.BMJ Global Healt
Material strength at high pressure
Get PDFOver the past 30 years, advancements in the focusing schemes, beam quality, and X-ray brilliance at synchrotron light sources have enabled the reduction of X-ray beam dimensions from tens of micrometers into the sub-micrometer domain. These developments have enabled spatial mapping of the stress state at multi-megabar pressures in the diamond anvil cell. This work presents angle-dispersive X-ray diffraction results collected on beamline P02.2 at the Petra-III synchrotron using a beam size (FWHM) of 0.85 x 0.85 microns on an Ir sample. Variations in the local stress state in the sample were analysed through two approaches based on X-ray diffraction peak shifting and broadening. The results of the two methods are compared and highlight the effectiveness of Bi as a pressure transmitting medium, even at multi-megabar pressures. We look to apply these techniques to future experiments into obtaining more precise investigations of phase transitions and material strength at extreme pressure.Engineering and Physical Sciences Research Council (EPSRC)AWE ScholarshipDefence and Security Doctoral Symposia 2024 (DSDS24
Mapping variability of mycotoxins in individual oat kernels from batch samples: implications for sampling and food safety
Get PDFOats are susceptible to contamination by Fusarium mycotoxins, including deoxynivalenol (DON), zearalenone (ZEN), and T-2/HT-2 toxins, posing food safety risks. This study analyses the variation in levels of 14 mycotoxins in 200 individual oat kernels from two DON-contaminated batch samples (mean = 3498 µg/kg) using LC-MS/MS. The samples also contained deoxynivalenol-3-glucoside (DON-3G), 3-acetyldeoxynivalenol (3-ADON), 15-acetyldeoxynivalenol (15-ADON), and ZEN. Contamination levels varied notably among individual kernels, with DON detected in 70% of them, followed by DON-3G (24.5%) and 3-ADON (20.5%). Importantly, 8% of kernels exceeded the EU legal limit for DON (1750 µg/kg), and some occasionally surpassed limits for ZEN and T-2/HT-2. Correlation analyses revealed strong associations between DON and its derivatives but weaker correlations with other toxins. Mycotoxin ratios varied widely, indicating that although they often co-occur, their concentrations differ between kernels. Contamination did not significantly impact kernel weight, though a slight trend toward lower weights in contaminated kernels was noted. Additionally, sampling statistics showed that as the percentage of selected kernels increased, the probability of batch sample rejection for DON contamination rose significantly. The study highlights the heterogeneity of mycotoxin contamination in oat batches, emphasising the importance of accurate detection and regulatory compliance to ensure safer oat-based products.This work was supported by the Spanish Ministry of Science and Innovation (Project PID2020-114836RB-I00 funded by MCIN/AEI/10.13039/501100011033) and by the Spanish Ministry of Universities (predoctoral grant FPU21/00073). Additionally, this research received funding from the EU Project 101079173-FunShield4Med (HORIZON-WIDERA-2021-ACCESS-03).Toxin
Virtual electroencephalogram acquisition: a review on electroencephalogram generative methods
Get PDFDriven by the remarkable capabilities of machine learning, brain–computer interfaces (BCIs) are carving out an ever-expanding range of applications across a multitude of diverse fields. Notably, electroencephalogram (EEG) signals have risen to prominence as the most prevalently utilized signals within BCIs, owing to their non-invasive essence, exceptional portability, cost-effectiveness, and high temporal resolution. However, despite the significant strides made, the paucity of EEG data has emerged as the main bottleneck, preventing generalization of decoding algorithms. Taking inspiration from the resounding success of generative models in computer vision and natural language processing arenas, the generation of synthetic EEG data from limited recorded samples has recently garnered burgeoning attention. This paper undertakes a comprehensive and thorough review of the techniques and methodologies underpinning the generative models of the general EEG, namely the variational autoencoder (VAE), the generative adversarial network (GAN), and the diffusion model. Special emphasis is placed on their practical utility in augmenting EEG data. The structural designs and performance metrics of the different generative approaches in various application domains have been meticulously dissected and discussed. A comparative analysis of the strengths and weaknesses of each existing model has been carried out, and prospective avenues for future enhancement and refinement have been put forward.This work was supported in part by the National Key R&D Program of China (project number: 2023YFC2506600; task number: 2023YFC2506601), and by the National Natural Science Foundation of China (Grant No. 62273017).Sensor
Predicted yield and soil organic carbon changes in agroforestry, woodland, grassland, and arable systems under climate change in a cool temperate Atlantic climate
Get PDFThe impact of a changing climate on crop and tree growth remains complex and uncertain. Whilst some areas may benefit from longer growing seasons and increased CO2 levels, others face threats from more frequent extreme weather events. Models can play a pivotal role in predicting future agricultural and forestry scenarios as they can guide decision-making by investigating the interactions of crops, trees, and the environment. This study used the biophysical EcoYield-SAFE agroforestry model to account for the atmospheric CO2 fertilization and calibrated the model using existing field measurements and weather data from 1989 to 2021 in a case study in Northern Ireland. The study then looked at two future climate scenarios based on the representative concentration pathways (RCP 4.5 and RCP 8.5) for 2020–2060 and 2060–2100. The predicted net impacts of future climate scenarios on grass and arable yields and tree growth were positive with increasing CO2 fertilization, which more than offset a generally negative effect of increased temperature and drought stress. The predicted land equivalent ratio remained relatively constant for the baseline and future climate scenarios for silvopastoral and silvoarable agroforestry. Greater losses of soil organic carbon were predicted under arable (1.02–1.18 t C ha−1 yr−1) than grassland (0.43–0.55 t C ha−1 yr−1) systems, with relatively small differences between the baseline and climate scenarios. However, the predicted loss of soil organic carbon was reduced in the long-term by planting trees. The model was also used to examine the effect of different tree densities on the trade-offs between timber volume and understory crop yields. To our best knowledge this is the first study that has calibrated and validated a model that accounts for the effect of CO2 fertilization and determined the effect of future climate scenarios on arable, grassland, woodland, silvopastoral, and silvoarable systems at the same site in Europe.We acknowledge the support of EU Horizon 2020 AGROMIX project under grant agreement 862993 and the DEFRA Nature for Climate Fund (NCF) England Tree Planting Programme (ETTP) Expanding Agroforestry project.Agronomy for Sustainable Developmen