The energy supply sector is undergoing massive technological changes to reduce its greenhouse gas emissions. At the same time, the climate is progressively changing creating new challenges for energy generation, networks and demand. The Adaptation and Resilience in Energy Systems (ARIES) project aims to understand how climate change will affect the UK gas and electricity systems and in particular its 'resilience'. A resilient energy system is one that can ensure secure balance between energy supply and demand despite internal and external developments such as climate change. The physical changes in climate up to 2050 coincide with the energy sector moving towards a low-carbon future, with massive renewables targets, new smart grid infrastructure and more active demand management. As such, it is of importance to identify whether new technology and policy strategies for reducing emissions also imply changes in energy system resilience. A particular concern is that increasingly large renewable energy targets aimed at decarbonisation may create new vulnerabilities given the weather-dependency of renewable energy sources. With affordable, secure energy critical to the UK economy it is imperative to fully understand the risk posed by changing climate for the energy supply sector and its infrastructure. ARIES will develop new methods to model the impacts of climate changes on current and new energy generation technologies and understand its effect on gas and electricity demand. It will identify the impacts that these new supply and demand patterns have on energy system resilience and will suggest changes or adaptation that can 'build-in' resilience.

Electrical power systems are undergoing unprecedented changes that increase the levels of complexity and uncertainty, mainly driven by decarbonisation targets on the way to achieving net zero operation and addressing climate change. As an example, towards this direction the UK government has set a bold target for zero carbon electricity by 2035. Increasing complexity comes from the introduction of a large number of converter-interfaced devices (CID) that exhibit very different dynamic behaviour, governed to a large extent by control. In addition, uncertainty in power system operation is increasing, due to the intermittent behaviour of renewable sources but also increasingly by social behaviour through EVs and potential electrification of heating as well as complex market and power industry structures. This leads to an exploding search space of possible operating conditions and contingencies, which is particularly challenging for computationally intensive stability assessment and dynamic studies. This aspect coupled with the increasing complexity of dynamic behaviour, makes identifying critical operating conditions and contingencies challenging. Consequently, these developments raise the need for improved representation and understanding of dynamic phenomena as well as fast and informative dynamic security and stability assessment. Both aspects are crucial in order to avoid potentially hidden risks of instability that in the worst-case scenario can lead to widespread events and even blackouts. Consequently, the aim of this proposal is to develop methods, tools and models needed to achieve a secure, resilient and cost-effective power system operation. Building on progress made in the initial part of the fellowship, the extension will continue focusing on two main directions. From one hand, it will develop tools, methods and models to represent and investigate the changing dynamic behaviour of power systems in order to capture new arising dynamic phenomena, spanning both transmission and distribution (e.g. offshore/onshore wind, solar PVs, HVDC links, EVs, heat pumps, electrolysers, etc.). On the other hand, it will develop novel machine learning based and data-driven methods for the fast and informative stability assessment as well as the estimation of the stability boundary. This direction will enable unique understanding of the dynamic behaviour that will lead to ancillary services and control to mitigate or alleviate the impact of disturbances and improve system security and resilience. In addition, the fellowship extension will continue and ramp-up engagement with industrial partners to capture practical aspects and fine tune developed methodologies to pave the way for real world applications. In effect, the results of the fellowship will enable more secure, resilient and potentially more cost-effective operation of power systems due to better knowledge of system stability limits. Consequently, much higher integration of renewables and new technologies with various technical and environmental benefits can be achieved in order to meet bold decarbonisation targets in a secure, resilient and cost-efficient manner.

Electrical power systems are undergoing unprecedented and ever-increasing change that will increase the levels of complexity and uncertainty to unprecedented levels, particularly in GB. Ensuring secure, reliable and stable power system operation is clearly paramount; not only for "traditional" electrical loads, but to power telecommunications, water supply and sanitation, natural gas production and delivery, and for transportation. Social discomfort, economic disruption and loss of life can arise in cases of partial or full blackouts. Uncertainty and complexity will arise due to the prevalence of Renewable Energy Sources (RES). In GB, millions of intermittent small energy sources (not under the control of the system operator) may be connected to the electricity distribution system in future, as opposed to historical arrangements, where a much smaller number (100 or so) of large-scale generators, under the control of the system operator, were connected to the transmission system. Furthermore, energy storage, electric vehicles, heat pumps, HVDC interconnectors, "smart grids" and associated control systems, will all act to increase the complexity and unpredictability of, and possibly introduce chaos to, the system. Extreme weather events are on the increase empirically and with reliance on renewable sources (mostly from solar and wind), this could also increase risks associated with uncertainty, complexity and system operability. Internationally respected organisations such as the IEEE and CIGRE emphasise the increasing complexity of power systems and highlight problems with unpredictable and changing power system dynamics as challenges that might compromise security and could increase the risk of blackouts. They also highlight potential improvements in reducing these risks through enhanced monitoring, control, automation and special protection schemes. Prevention and mitigation of the risk of blackouts is essential and the focus of this proposal. Understanding the changing nature of system dynamics is fundamental to addressing this risk. This Fellowship is focused on investigating, understanding, defining and representing previously un-encountered dynamic phenomena that will be manifest in future power systems due to the aforementioned increases in complexity and uncertainty. Novel modelling, prediction and control tools and methodologies will be developed to ensure an accelerated path to stable, secure, reliable and cost-effective operation and enhance understanding. This research will lead to prototype applications and demonstration in the world-leading facilities available at the host institution. Ultimately, the main impact will be maximisation of the secure use of renewables and effective decarbonisation of the electricity system, through creating models and tools to enhance "operability" of electrical power systems and reduce blackout risk. The Fellowship will enable the candidate and his institution to be international leaders in this field, which impacts both society and the economy.

The target of operating the GB system with net-zero carbon by 2025, alongside China's ambitious renewable of 35% of energy from renewable sources by 2030, are extremely challenging. From the recent UK power cut event (2019) , several other non-high profile (but still concerning) events that are known to the UK investigators, and the wide-scale blackouts caused by Typhoon Lekima in China, it is clear that new capabilities to manage extreme events and to maximise system resilience are needed urgently. Existing protection and control methods and practices have limitations, and presently islanded or city-centric operational modes are not permitted. The ambition of the project is to enable future urban energy systems, in island or multiple-island mode, with the capability of surviving in extreme conditions purely using local energy and storage resources without compromising system resilience or security of supply. The novelty of the project is in measurement and enhancement of resilience at an urban scale, and in fundamentally inverting operation, protection and control philosophies to enable migration from systems relying on centralised power stations and a national transmission system, to being capable of surviving purely with local sustainable sources, functioning in a proactive and co-ordinated approach. Key outputs of the project will be methods to audit, model and measure resilience of cities, and methods to determine and evaluate "threat levels" for future urban energy systems and their operation. Additionally, the project will develop control and protection strategies for operation in extreme conditions in islanded/sub-islanded modes, as well as develop enhanced restoration methods.

The movement of electrical energy from generators to customers, through electricity networks, has historically been based on High Voltage Alternating Current (HVAC) technology. This has been a major success of the twentieth century, enabling reliable and stable energy supplies across the developed world. The technology dominated partly as a result of the ability to change voltage levels readily and efficiently using transformers. The alternative technology of High Voltage Direct Current (HVDC) has historically only been used for point-to-point links because of particular advantages in this situation. Now however, with the advent of power electronics, utilisation of HVDC systems is rapidly increasing across the world. This has been accelerated with the growth of renewable distributed energy supplies, such as offshore wind farms in the UK. As a result, local and international energy supplies are becoming dependent on HVDC. Consequently, the reliability of DC technologies is becoming critical as they become more embedded in supply networks. However, in comparison to AC systems, the understanding of insulation and plant reliability under HVDC is still in its infancy. At the same time, the working environment for DC plant is not well documented and, in reality, DC systems have AC ripple, impulses and voltage variation just as in any other system, and these time-varying waveforms are likely to control plant ageing and reliability. This project comprises internationally leading researchers from The University of Manchester, The University of Strathclyde and Imperial College. They bring complementary expertise to form a unique team to address the problem. Prof Tim Green (Imperial) is an expert in the use of power electronics to enhance the controllability and flexibility of electricity networks; Prof Simon Rowland (Manchester) is an authority on ageing of high voltage insulation materials; and Prof Brian Steward (Strathclyde) has unique experience in condition monitoring and insulation diagnostics for high voltage systems. The project is designed to embed the work into the global community and in particular is linked to researchers in China where the largest systems are being developed. This project will firstly identify the voltage profiles experienced by plant insulation in a real HVDC network or link, because in real systems the voltage on the network is not a constant, fixed value. The power converters that feed a DC network create intrinsic "noise" in the form of high frequency elements as part of their normal operation, and also create voltage disturbances in their responses to fault conditions and emergency overloads. Characterising these is the first step in the overall study of how DC power quality impacts the lifetime of HV insulation. The team will then, through laboratory exploration, develop life models for polymeric insulation subject to known levels of DC power quality. The focus will be on AC ripple over a wide frequency range. In addition, the influence of fast transient signals of varying levels and durations will be considered, as identified above. The third experimental theme is to develop tools for monitoring transient signals and power quality in a real DC cable setting, and enable subsequent interpretation. Finally, we will develop input for utility policy documents on acceptable DC power quality. We will also provide evidence for optimal insulation design for equipment manufacturers and asset management recommendations for utilities. Through these means we hope to de-risk the UK's growing dependence on DC networks, and optimise equipment and system design and operation.