Contrail cirrus clouds, that evolve from line-shaped clouds that form in the wake of aircraft in the middle and upper troposphere, are an important part of the climate impacts of aviation. The increasing use of sustainable aviation fuels (SAFs) may not only reduce CO2 emissions but is also thought to have the advantage of shorter-lived contrails. However, to quantitatively predict the magnitude of this benefit we need to improve our fundamental understanding of contrail formation and the emission of ice-forming particles from the use of different SAFs and SAF-blends. The link between ice crystals number, crystal size and emitted aerosol. The radiative properties and lifetime of contrail cirrus are strongly affected by the number concentration of ice-forming particles in the engine exhaust. Contrails form when ambient air and exhaust plumes mix resulting in a supersaturation with respect to water where liquid water can condense on particles. At temperatures below homogeneous freezing (~-38°C), these droplets almost instantly freeze and then grow into ice crystals. If the background atmosphere is supersaturated with respect to ice, then these crystals continue to grow forming a persistent contrail. The fewer aerosol that are emitted the fewer ice crystals that can form, the larger these crystals grow, the more rapidly they sediment and the shorter the lifetime of the contrail, thus reducing the fraction of the atmosphere containing contrails. The overarching goal of SAFice is to quantify the change in the contrail radiative effect on transitioning to sustainable aviation fuels from standard fossil Jet A1 fuel. This will be achieved through: 1. Probing experiments: Aerosol chamber and PINE (Portable Ice Nucleation Experiment) measurements in Leeds to examine the competition between non-volatile soot and lubrication oil, as well as between aircraft emissions and proxies of background atmospheric aerosol. 2. Gas turbine experiments: Experiments in Sheffield to examine the contrail-ice-forming potential of turbine exhaust using a range of SAFs and blends making use of an aircraft turbine engine and our PINE instrument. This will be much more detailed than could ever be achieved flying aircraft. 3. Global contrail simulations: Define new parameterisation based on the laboratory data and use them to quantify contrail properties and radiative effects with a range of SAF usage scenarios. This is timely because we are at the cusp of the transition to SAF (with the first 100% SAF trans-Atlantic flight having taken place in Nov '23) and we need to understand the impact of this transition. The newly opened Translational Energy Research Centre (TERC) has developed a state-of-the-art facility comprising a turbine engine (APU) that has been shown to run on SAF fuels as well as having the connections to SAF producers and end users through the SAF clearing house. In Leeds we have developed an instrument for quantifying the concentration of ice forming particles - PINE. In Imperial we have developed modelling tools (pycontrails) which require our basic experimental input to make predictions of the effect of the switch to SAF on global contrail cirrus radiative properties. The team have also recently published the first ever study on the role of lubrication oil droplets in contrail formation and collaborated on the first 100% SAF flight operated by Virgin Atlantic, where TERC was used to measure changes in particle emissions resulting from the SAF used for the flight.

Achieving carbon neutrality targets by 2050 is widely recognised as the most formidable challenge globally, whilst simultaneously a key opportunity to build a greener future for the next generations. Utilisation of renewable energy sources (e.g., wind, solar) is largely addressing the net-zero commitment on energy transition, but this will only address 55% of all emissions. Materials-based net zero, contributing to the remaining 45%, are more challenging due to the unavoidable utilisation of carbon products especially Carbon-containing Engineering Materials (CEMs) such as polymers, chemicals, and composites. CEMs are ubiquitous to industries but around 90% of these CEMs are produced from fossil resources. Even though alternative carbon sources (e.g., biomass, wastes, and CO2) and various decarbonisation pathways (e.g., CO2/H2-to-chemicals, power-to-chemicals) are currently under investigation, the criteria to systematically evaluate the carbon matrix comprising not just the carbon footprint but also the quality of carbon resource is lacking. This FLF will provide the evidence base to develop a carbon measuring framework by expanding the current carbon measuring matrix to not only quantify the carbon emission, but also embed carbon quality as a new dimension. Adopting this new framework, the existing net-zero technologies will be reassessed and new zero-waste solutions will be identified. The impact will be maximised by developing national/global material-based net-zero strategic guidelines that address the United Nations' Sustainable Development Goals (SDGs) 11-13 and guide future industry direction, policy making, and public acceptance.

Converting biomass waste to bio-products will simultaneously provide a route to waste-disposal, and a process for the production of useful, economically attractive products. Within all the products derived from biomass waste, liquid hydrocarbon transport fuels are promising for the UK to meet its 2020 renewable energy target of providing 10% of its transport fuel from renewable sources. They will help to tackle the challenges of climate change and the ever-increasing fuel demand. The current waste-to-liquid technologies, however, are facing main problems of high production cost and technical uncertainty. To address these problems, we will develop a breakthrough technology in this project. This novel technology will co-produce liquid transport bio-fuel and one value-added bio-chemical. By doing this, high economic profits will be expected when comparing with conventional liquid bio-fuel plants. The co-production system will additionally benefit to the reduction of the biofuel's high oxygen content, which is known as the main source that leads to poor stability, immiscibility and low calorific value of the produced fuel. The integrated production system will be designed and evaluated within this project, with the involvement of three universities (Queen's University Belfast-QUB, Aston University-AU, and North China Electric Power University-NCEPU), three academics, one PDRA, and two PhDs (one is funded by QUB, the other is funded by NCEPU). The project is also highly industrial geared by directly involvement of two UK-based companies: Hirwaun Energy Ltd, who will provide a pilot scale biomass pyrolysis reactor for results validation, and Green Lizard Technologies Ltd, who will provide suggestions on the technology scale-up. Through the development of this innovative technology, high national impact will be realised to achieve the UK's 2020 Renewable Energy targets through the conversion of over 16 million tonnes per year of the UK's lignocellulosic biomass into advanced fuel together with value-added co-products. It will also have a positive impact on the UK's target of reducing carbon dioxide emissions and increasing the use of renewable materials.

Converting biomass waste to bio-products will simultaneously provide a route to waste-disposal, and a process for the production of useful, economically attractive products. Within all the products derived from biomass waste, liquid hydrocarbon transport fuels are promising for the UK to meet its 2020 renewable energy target of providing 10% of its transport fuel from renewable sources. They will help to tackle the challenges of climate change and the ever-increasing fuel demand. The current waste-to-liquid technologies, however, are facing main problems of high production cost and technical uncertainty. To address these problems, we will develop a breakthrough technology in this project. This novel technology will co-produce liquid transport bio-fuel and one value-added bio-chemical. By doing this, high economic profits will be expected when comparing with conventional liquid bio-fuel plants. The co-production system will additionally benefit to the reduction of the biofuel's high oxygen content, which is known as the main source that leads to poor stability, immiscibility and low calorific value of the produced fuel. The integrated production system will be designed and evaluated within this project, with the involvement of three universities (Queen's University Belfast-QUB, Aston University-AU, and North China Electric Power University-NCEPU), three academics, one PDRA, and two PhDs (one is funded by QUB, the other is funded by NCEPU). The project is also highly industrial geared by directly involvement of two UK-based companies: Hirwaun Energy Ltd, who will provide a pilot scale biomass pyrolysis reactor for results validation, and Green Lizard Technologies Ltd, who will provide suggestions on the technology scale-up. Through the development of this innovative technology, high national impact will be realised to achieve the UK's 2020 Renewable Energy targets through the conversion of over 16 million tonnes per year of the UK's lignocellulosic biomass into advanced fuel together with value-added co-products. It will also have a positive impact on the UK's target of reducing carbon dioxide emissions and increasing the use of renewable materials.

The Centre for Doctoral Training in Green Industrial Futures (CDT-GIF) will deliver the next generation of global leaders in the energy transition, through a world-leading, interdisciplinary whole systems research and training programme to address national and global priorities to realise the green industrial revolution. The CDT-GIF is critically important, as skill shortages are currently limiting the opportunities of the green industrial revolution, adding significant risk of loss of economic and social value. For example, over 350,000 additional jobs (28% professional roles) are required to meet the demands of the current UK industrial cluster decarbonisation projects between 2025 to 2040. Therefore, there is a substantial and pressing demand for training doctoral-level graduates to fill these roles to drive R&D for industrial decarbonisation, lead critical important decarbonisation projects, and prepare future graduates for the net zero agenda. The CDT-GIF directly addresses this and is in closed alignment with the EPSRC mission inspired priority 'Engineering Net Zero' by providing an industry-guided, interdisciplinary training environment in transformative low-carbon technologies that will uniquely train 100 doctoral students, whilst leveraging significant investment from academic and industry partners. Four institutions with global standing in decarbonisation (Heriot-Watt University, Imperial College London, University of Bath and University of Sheffield) have partnered with a comprehensive range of stakeholders to ascertain the critically in-demand skills and knowledge that prospective employers are seeking to deliver net zero industries. These include technically trained on systems thinking, career ready and industry literate, and internationally connected. As a result, we have co-developed a training programme, based on three pillars, that will equip our students with these attributes, namely: (1) a cohort-based whole systems taught training programme (2) metaskills development programme (Net Zero Leadership Programme), and (3) unrivalled international opportunities to visit world-leading facilities, e.g. National Carbon Capture Centre (USA), ECCSEL (European network), Heriot-Watt Dubai campus and UNECE Sustainability Week. The training elements of the programme will run parallel to student's research in order to ensure cohesive learning within and across yearly cohorts, building peer-to-peer networks. A series of activities have been designed to foster a cohesive cohort trained in a diverse and inclusive environment that engenders a culture of environmental sustainability, research trust and responsible research and innovation. The CDT-GIF research and training programme is centred on four technological themes, with one cross-cutting systems theme: (1) Advancing carbon capture, utilisation and storage technologies, (2) Green hydrogen & low carbon fuels, (3) Developing next generation CO2 removal technology, (4) Energy processes, systems integration & resource efficiency, and (5) Integrated thematic areas including socio-behavioural change, policy & regulation and net zero economics related to the four technological themes. Within these themes, students will undertake challenging & original research projects that will be co-created with industrial collaborators to discover transformative, responsible and integrated solutions to achieve net zero. Challenging and original research projects will be rooted in one of these research themes, as well as across three integrated thematic areas and supervised by >75 internationally recognised researchers with excellent track record of doctoral supervision. In summary, CDT-GIF has the capacity, expertise and unique training opportunities to deliver the most comprehensive and transformational Centre for Doctoral Training to realise the green industrial revolution.