An integrated approach to planning charging infrastructure for battery electric vehicles

PhD ThesisBattery electric vehicles (BEVs) could break our dependence on fossil fuels by facilitating the transition to low carbon and efficient transport and power systems. Yet, BEV market share is under 1% and there are several barriers to adoption including the lack of charging infrastructure. This work revealed insights that could inform planning an appropriate charging infrastructure to support the transition towards BEVs. The insights were based on analysis of a comprehensive dataset collected from three early, real world demonstrators in the UK on BEVs and smart grids. The BEV participants had access and used home, work and public charging infrastructure including fast chargers (50 kW). Probabilistic methods were used to combine and analyse the datasets to ensure robustness of findings. The findings confirm that it is essential to consider a new refuelling paradigm for BEV charging infrastructure and not replicate the liquid-fuel infrastructure where all demand is met at public fuelling stations in a very short period of time. BEVs could be charged where they are routinely parked for long periods of time (i.e. home, work) and meet most of the charging needs of drivers. Installing slow charging infrastructure at home and work would be less expensive and less complicated than rolling-out a ubiquitous fast charging infrastructure to meet all charging needs. In addition, ensuring that cars are connected most of the time to the electricity network allows proper management of BEV charging demand. This could support reliable and efficient operation of the power system to minimise network upgrade costs. Finally, when slow charging infrastructure is neither available nor practical to meet charging needs, fast chargers can be used to fill in this gap. Analysing data of BEV drivers with access to private charging locations, the findings show that fast chargers become more important than slow chargers for daily journeys above 240km and could help overcome perceived and actual range barriers. An appropriate infrastructure takes an integrated approach encompassing BEV drivers’ requirements and the characteristics of the distribution networks where BEV charging infrastructure is connected. A non-integrated approach to delivering a charging infrastructure could impede the transition towards BEVs. The findings of this work could support on-going policy development in the UK and are crucial to planning national charging infrastructure to support the adoption of BEVs in a cost-optimal manner

An integrated approach to planning charging infrastructure for battery electric vehicles

PhD ThesisBattery electric vehicles (BEVs) could break our dependence on fossil fuels by facilitating the transition to low carbon and efficient transport and power systems. Yet, BEV market share is under 1% and there are several barriers to adoption including the lack of charging infrastructure. This work revealed insights that could inform planning an appropriate charging infrastructure to support the transition towards BEVs. The insights were based on analysis of a comprehensive dataset collected from three early, real world demonstrators in the UK on BEVs and smart grids. The BEV participants had access and used home, work and public charging infrastructure including fast chargers (50 kW). Probabilistic methods were used to combine and analyse the datasets to ensure robustness of findings. The findings confirm that it is essential to consider a new refuelling paradigm for BEV charging infrastructure and not replicate the liquid-fuel infrastructure where all demand is met at public fuelling stations in a very short period of time. BEVs could be charged where they are routinely parked for long periods of time (i.e. home, work) and meet most of the charging needs of drivers. Installing slow charging infrastructure at home and work would be less expensive and less complicated than rolling-out a ubiquitous fast charging infrastructure to meet all charging needs. In addition, ensuring that cars are connected most of the time to the electricity network allows proper management of BEV charging demand. This could support reliable and efficient operation of the power system to minimise network upgrade costs. Finally, when slow charging infrastructure is neither available nor practical to meet charging needs, fast chargers can be used to fill in this gap. Analysing data of BEV drivers with access to private charging locations, the findings show that fast chargers become more important than slow chargers for daily journeys above 240km and could help overcome perceived and actual range barriers. An appropriate infrastructure takes an integrated approach encompassing BEV drivers’ requirements and the characteristics of the distribution networks where BEV charging infrastructure is connected. A non-integrated approach to delivering a charging infrastructure could impede the transition towards BEVs. The findings of this work could support on-going policy development in the UK and are crucial to planning national charging infrastructure to support the adoption of BEVs in a cost-optimal manner

An Overview of Cyber Security and Privacy on the Electric Vehicle Charging Infrastructure

Electric vehicles (EVs) are key to alleviate our dependency on fossil fuels. The future smart grid is expected to be populated by millions of EVs equipped with high-demand batteries. To avoid an overload of the (current) electricity grid, expensive upgrades are required. Some of the upgrades can be averted if users of EVs participate to energy balancing mechanisms, for example through bidirectional EV charging. As the proliferation of consumer Internet-connected devices increases, including EV smart charging stations, their security against cyber-attacks and the protection of private data become a growing concern. We need to properly adapt and develop our current technology that must tackle the security challenges in the EV charging infrastructure, which go beyond the traditional technical applications in the domain of energy and transport networks. Security must balance with other desirable qualities such as interoperability, crypto-agility and energy efficiency. Evidence suggests a gap in the current awareness of cyber security in EV charging infrastructures. This paper fills this gap by providing the most comprehensive to date overview of privacy and security challenges To do so, we review communication protocols used in its ecosystem and provide a suggestion of security tools that might be used for future research.Comment: 12 pages, 5 tables, 3 figure

Effect of the Soil Spatial Variability on the Static and Dynamic Stability Analysis of a Lebanese Slope

The accidental topography and heterogeneous Lebanese geology in addition to the active seismicity have initiated the static and dynamic stability analysis of Lebanese slopes. In this paper, the stability of a sandy Lebanese slope situated at Mansourieh near Beirut is investigated using deterministic and probabilistic approaches. The characterization of the variability of the slope soil properties is done based on geological investigation, as well as geophysical (Resistivity and Ambient noise) and geotechnical tests performed on this slope. Three dimensional 3D static deterministic analyses is performed to determine the overall safety factor of the slope and to find the location of the critical failure surface. The deterministic model is based on numerical simulations using the finite difference code FLAC3D. Then, two-dimensional probabilistic analysis is carried out on the critical section obtained from the 3D model. In the probabilistic analysis, the soil properties are modeled using the random field theory. An efficient uncertainty propagation methodology based on the expansion optimal linear estimation EOLE method is used to discretize the random field. Concerning the dynamic analysis, it is implemented in order to determine the amplification at the top of slope, where the looseness of the soil there may amplify the earthquake acceleration. The results have shown a small safety factor as well as high amplification. The importance of using the probabilistic approach versus the deterministic one is also presented and discussed

Securing the Electric Vehicle Charging Infrastructure

Electric Vehicles (EVs) can help alleviate our reliance on fossil fuels for transport and electricity systems. However, charging millions of EV batteries requires management to prevent overloading the electricity grid and minimise costly upgrades that are ultimately paid for by consumers. Managed chargers, such as Vehicle-to-Grid (V2G) chargers, allow control over the time, speed and direction of charging. Such control assists in balancing electricity supply and demand across a green electricity system and could reduce costs for consumers. Smart and V2G chargers connect EVs to the power grid using a charging device which includes a data connection to exchange information and control commands between various entities in the EV ecosystem. This introduces data privacy concerns and is a potential target for cyber-security attacks. Therefore, the implementation of a secure system is crucial to permit both consumers and electricity system operators to trust smart charging and V2G. In principle, we already have the technology needed for a connected EV charging infrastructure to be securely enabled, borrowing best practices from the Internet and industrial control systems. We must properly adapt the security technology to take into account the challenges peculiar to the EV charging infrastructure. Challenges go beyond technical considerations and other issues arise such as balancing trade-offs between security and other desirable qualities such as interoperability, scalability, crypto-agility, affordability and energy efficiency. This document reviews security and privacy topics relevant to the EV charging ecosystem with a focus on smart charging and V2G