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This paper discusses the resilience of power systems in the context of other interdependent critical infrastructure systems. Potential sources of disruption are explained, and their interconnected impacts are discussed. The theoretical frameworks for assessing reliability and resilience across electricity, gas, water, telecommunications and transport networks are presented, and a new approach is proposed for integrating these approaches into a unified resilience assessment framework. The CIGRE C4.47 resilience definition is generalised, and promising new methodologies are explored.

Electricity network transformation has been in the forefront of research and industrial development for at least a decade. Multiple approaches have been proposed. The concept of Smart Grids has emerged in the beginning of this century, as a solution that would enable an ageing infrastructure to maintain its safe and cost-effective operation throughout the decades to follow. Large load and generation changes were forecasted, and making the power system adaptable, “smart” and highly controllable became some of the key goals. However, there are technologies that show great promise but have been receiving very little attention. One of those technologies is electricity distribution using Direct Current (DC), rather than the usual Alternating Current (AC). This document presents the key advantages of this technology, as well as the ways that it can be integrated into current Smart Grid efforts.

Distribution system operators, suppliers, vendors and policy makers lack a common framework in terms of guidelines and recommended practices on the way BESSs should be integrated into the distribution networks of the future. WG C6.30 entitled "The Impact of Battery Energy Storage Systems on Distribution Networks" was set up by SC C6 and approved by the CIGRE TC, to complement and update earlier work carried out by the WGs 6.15 (Electric Energy Storage Systems). This brochure focuses on the following topics: 1) Planning and design considerations for BESS in distribution systems;2) Operational considerations for BESS in distribution systems;3) Use-cases and business cases for BESS in distribution systems;4) Standards and Grid Codes for BESS in distribution systems;5) Practical international experiences with BESS in distribution systems.

The benefits of integrating aggregated Electric Vehicles (EV) within the Virtual Power Plant (VPP) concept, are addressed. Two types of EV aggregators are identified: i) Electric Vehicle Residential Aggregator (EVRA), which is responsible for the management of dispersed and clustered EVs in a residential area and ii) Electric Vehicle Commercial Aggregator (EVCA), which is responsible for the management of EVs clustered in a single car park. A case study of a workplace EVCA is presented, providing an insight on its operation and service capabilities.

The key question this thesis aims to address is to what extent can micro-generation sources contribute to the carbon emission reduction targets set by the UK government.\ud The operational emissions of micro-CHP capable micro-generators were examined against the UK grid electricity and gas boiler heat. Fossil and biomass fuels were considered. The life-cycle emissions associated with the manufacturing, transport and disposal of micro-generators were calculated. Case studies were constructed, based on the literature. It was found that emissions associated with domestic electrical and thermal demand would be reduced significantly.\ud A Virtual Power Plant (VPP) was defined for aggregating micro-generators, using micro-generation penetration projections for the year 2030 from the literature. An optimisation problem was described, where the goal was to minimise the VPP carbon emissions. The results show the amount of emissions that would potentially be reduced by managing an existing micro-generation portfolio in a VPP.\ud An Environmental Virtual Power Plant (EVPP) was defined, for controlling micro-generator carbon emissions. A multi-agent system was designed. The principle of operation resembles an Emissions Trading Scheme. Emission allowances are traded by the micro-generators, in order to meet their emissions needs. Three EVPP control policies were identified. Fuzzy logic was utilised for the decision making processes. Simulations were performed to test the EVPP operation. The main benefit for the micro-generators is the ability to participate in markets from which they would normally be excluded due to their small size.\ud The multi-agent system was verified experimentally using micro-generation sources installed in two laboratories, in Athens, Greece. Two days of experiments were performed. Results show that system emissions have been successfully controlled, since only small deviations between desired and actual emissions output were observed. It was found that Environmental Virtual Power Plant controllability increases significantly by increasing the number of participating micro-generators.