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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.

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.

Railway is currently envisioned as the most promising transportation system for both people and freight to reduce atmospheric emission and combat climate change. In this context, ensuring the energy efficiency of the railway systems is paramount in order to sustain their future expandability with minimum carbon footprint. Recent advancements in computing and communication technologies are expected to play a significant role to enable novel integrated control and management strategies in which heterogeneous data is exploited to noticeably increase energy efficiency. In this paper we focus on exploiting the convergence of heterogeneous information to improve energy efficiency of railway systems, in particular on the heating system for the railroad switches, one of the major energy intensive components. To this aim, we define new policies to efficiently manage the heating of these switches exploiting also external information such as weather and forecast data. In order to assess the performance of each strategy, a stochastic model representing the structure and operation of the railroad switch heating system and environmental conditions (both weather profiles and specific failure events) has been developed and exercised in a variety of representative scenarios. The obtained results allow to understand both strengths and limitations of each energy management policy, and serves as a useful support to make the choice of the best technique to employ to save on energy consumption, given the system conditions at hand.

This data represents the input and output data for the optimisation model developed in "Multi-objective Optimisation of Power-to-Mobility in Decentralised Energy Systems". The input data is specific to the case study used in the paper and includes: 1. The electricity and heating loads for each building (please note that although 50 buildings are used in the case study, two-family homes have been grouped together to result in 35 listed in these files) and solar radiation on the rooftop are included for the representative days horizon in "Building Loads Representative days 2018.xls", "Building Loads Representative days 2035.xls" and "Building Loads Representative days 2050.xls" 2. The driving profiles for each vehicle are found in "Charging profiles with driving cycles.xlsx". This includes profiles for the highway, average, and urban cycle profiles with the representative days horizon and the binary to indicate whether or not a vehicle is at home. 3. "Car2building.json" maps each vehicle index to the associated building. 4. "Power limit per building.xlsx" shows the maximum amount of power per building in the case study. 5. "PV Maximum Area per rooftop.xlsx" is the maximum area on each rooftop available for solar PV installation taken from the Sonnendach data set (https://www.uvek-gis.admin.ch/BFE/sonnendach/). Please note that all other input variables are indicated in Appendix B. The output data from the optimisation includes three file types for the three years (2018, 2035, and 2050) and for the Pareto optimum solutions and the reference case solutions: 1. "Sizing and Storage Operation" includes the sizing of conversion and storage technologies (sheets "PVCapacity" for PV and "TechCapacity" for all others) and the selection of vehicle technologies (sheet "Car_selection"). The charging, discharging (sheets "ChDsch"), and storage level ("Level") of all storage technologies for each Pareto solution are also included. The discharging of the vehicles back to the buildings is also in ("VBiDi"). This sheet also includes the calculation of the costs ("TechCost") and emissions ("TechCO2") 2. "Conversion Tech and Vehicle Charging" includes the energy consumed by conversion technologies ("InOps") and the energy produced by conversion technologies ("OutOps"). The PV output has its own tab in ("PVOps"). Vehicle charging in the community or at home is performed in ("VCharg") and public charging is performed in ("PCharg"). 3. "Export and Import" includes the energy carriers exported ("Export") and imported ("Import") into the system.

Full data table for Carbon content, Nitrogen content, and biovolume measurements of planktic Rhizaria. This data is associated with the publication: Mansour, J.S., Norlin, A., Llopis Monferrer, N., L'Helguen, S., and Not, F. (2020). Carbon and nitrogen content to biovolume relationships for marine protists of the Rhizaria lineage (Radiolaria and Phaeodaria). Limnol. Oceanogr. doi: 10.1002/lno.11714 Rhizaria are ubiquitous in oceanic waters. They have previously been underestimated due to their fragility, but recent (molecular) studies show that they are major components of the planktic community and contribute greatly to, among others, the carbon and silica flux. This study provides key data on the carbon and nitrogen content of Rhizaria and its relation to cell biovolume. Here presented are the raw data of measured (CN Elemental Analyzer) carbon and nitrogen content of Rhizaria (i.e. specifically Collodaria, Acantharia, Nassellaria, Spumellaria, Aulacantha, Protocystis, and Challengeria), as well as picture-based estimates of biovolume and derived characteristics. The biovolume-to-mass relationship for these protists has allowed the formulation of mass-to-volume equations and ratios that can be used to estimate mass from biovolume. Our data shows that global Rhizaria biomass might have in fact still been underestimated. This will be pivotal information for studies of ocean ecology and for modeling biomass fluxes, whether it is biogeographic or smaller-scale system dynamics.

- Database of African Renewable Energy Policies, based on publicly available soures, e.g. World Bank, IRENA, IEA, Climatescope.- Country sample: Algeria, Angola, Benin, Botswana, Burkina Faso, Burundi, Cameroon, Cape Verde, Côte d‘Ivoire, Democratic Republic of the Congo, Egypt, Ethiopia, Gabon, Gambia, Ghana, Guinea, Kenya, Madagascar, Malawi, Mali, Mauritius, Morocco, Mozambique, Namibia, Nigeria, Rwanda, Senegal, South Africa, Tanzania, Togo, Tunisia, Uganda, Zambia and Zimbabwe.- Renewable energy policy mapping according to policy content, actor constellation, transformative potential of each policy.Publication: Is Green a Pan-African Colour? Mapping African Renewable Energy Policies and Transitions in 34 Countries, in: Energy Research and Social Science

The main aim of study is examing farmers understanding towrds the emerging concepts of sustainable agricultural waste management falls under circular agriculture-a circular, green economy with cleaner production and bioeconomy reconciled with economic, social and environmental dimensions. This study is a prototype in Mirab Gojjam Zone of Amhara region as well in Ethiopia. we seek to determine farmers’ willingness-to-pay (WTP) for eco-friendly AWM. Data were collected through a contingent valuation survey of 353 randomly selected farmers in Mirab Gojjam. The improper discarding and unsafe use of agricultural waste causes health and environmental problems. It also contributes to GHG emissions, particularly in Mirab Gojjam, the focus of our study. We thus assessed farmers’ WTP for eco-friendly AWM to improve the local environment in Mirab Gojjam and maintain low carbon sustainable development. The result indicates an annual WTP of 6.84 household days (equivalent to 273.5 Birr) for the surveyed farmers. The Tobit results indicate that the social capital, socioeconomic, cognitive, and altruism variables significantly influence the degree of WTP. Our results are thus useful for understanding farmers’ attitudes and WTP for eco-friendly AWM, as well as the need for private and public instruments in agricultural waste for developing and disseminating resource technology.To improve the use of agricultural waste in biofuel, construction, and feedlot and to enhance sources of rural income, green marketing and low-carbon innovative recycling technologies should be established parallel to proper discarding. In our study, the mean WTP in labour days per year was higher than the amount of money farmers that were willing to pay for eco-friendly AWM.We thus propose three suggestions for sustainable and eco-friendly AWM. First, the government must assess and understand the current generation potential of agricultural waste. It must formulate rural sustainable waste management policies and create awareness accordingly.Second, agricultural waste recycling technology should be provisioned in rural areas through public–private collaboration. The vacuum in the local waste recycling market should be addressed by opening the market to private and informal micro-enterprise sectors, along with full government support.Lastly, proper follow-up and inspection is important to ensure all parties function in accordance with the laws, norms, and policies.Generally speaking, AWM must be prioritised as much as other SDGs to sustain holistic development, cleaner production, and clean-living environments for reducing carbon emission and looping conventional waste into circular agriculture.

1.- Data for Tulancingo City, Mexico. Monthly cloudiness calculation for insulation correction in the spatial process. Include the graphic of monthly results. (Excel) 2.- Data exported by ASrcGis and calculation of Indices. (Excel) 3.- Statistics (Excel)

This dataset contains temperature and rainfall data obtained from the Zambia Meteorological Department and maize yield data obtained from the Central Statistical Office aggregated at the district level for 30 years. The beans yield data is available upon request. Further, we merge this data with rainfall and temperature predictions from the HadGEM-ES2 global circulation model.