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This paper investigates voltage fluctuations caused by the operation of battery energy storage (BES) units which provide frequency response (FR) and fast frequency response (FFR) services using a test network based on a typical part of the United Kingdom (UK) mainland system. This paper provides an overview of current FR/FFR services currently used in the UK, and a summary of their typical modes of operation. Using DIgSILENT Powerfactory, the paper introduces a simple frequency disturbance generator to mimic typical frequency disturbances that would occur in the UK network, and then subsequently uses a representative test distribution network to show how voltage disturbances associated with BES units can develop across the electrical network. The paper provides a contribution to knowledge by creating a systematic approach for assessing voltage disturbance and flicker concerns for BES units on island networks, using a simple control algorithm and novel frequency disturbance generator. [ABSTRACT FROM AUTHOR]

This paper presents a new data-driven modelling framework for forecasting probabilistic flood inundation maps for real-time applications. The proposed end-to-end (rainfall–inundation) method combines a suite of machine learning (ML) algorithms to forecast discharge and deliver probabilistic flood inundation maps with a 3 h lead time. To classify wet/dry cells, the method applies rainfall–discharge models based on random forest technique on top of classifiers based on multi-layer perceptron. The hybrid modelling framework was tested using two subsets of data created from an observed fluvial flood event in a small flood-prone town in the UK. The results showed that the model can effectively emulate the outcomes of a hydrodynamic model (Flood Modeller (FM)) with considerably high accuracy measured in terms of flood arrival time error and classification accuracy. The mean arrival time difference between the proposed model and the hydrodynamic model was 1 h 53 min. The classification accuracy was measured against a synthetic aperture radar image, producing accuracies of 88.22% and 86.58% for the proposed data-driven model and FM, respectively. The key features of the proposed modelling framework are that it is simple to implement, detects flooded cells effectively and substantially reduces computational time. [ABSTRACT FROM AUTHOR]

Hybrid energy storage system (HESS) based on Li-ion and supercapacitor (SC) can play a potential role to stabilize the grid by providing the fast frequency ancillary services. The SC helps to reduce the battery charge/discharge stress and, hence, assists to extend the battery lifespan. The power sharing method (PSM) is the heart in control part to improve the HESS performance and reduce the battery stress. This paper proposes a hybrid PSM and investigates its impact on battery life extension along with its relation to the system design and regulation signal. The performance of hybrid PSM is compared with three other PSMs (low-pass filter, first and second rule based) in a 10 MW/10 MWh full-active parallel HESS for frequency regulation service in two networks: U.K. (national grid) and USA (PJM). Considering maximum possible battery lifetime upto 25 years, result shows that the hybrid PSM approach allows a degree of the better performance for both grid while the sharing of SC is kept maximum 2.0% and 2.5% (for U.S. and U.K. grid, respectively) of the HESS capacity. This study also analyses the impact of PSM on shared capacity and design of HESS for different grid regulation signals. [ABSTRACT FROM AUTHOR]

This study explores the feasibility of integrating battery technology into electric buses, addressing the imperative to reduce carbon emissions within the transport sector. A comprehensive review and analysis of diverse literature sources establish the present and prospective landscape of battery electric buses within the public transportation domain. Existing battery technology and infrastructure constraints hinder the comprehensive deployment of electric buses across all routes currently served by internal combustion engine counterparts. However, forward-looking insights indicate a promising trajectory with the potential for substantial advancements in battery technology coupled with significant investments in charging infrastructure. Such developments hold promise for electric buses to fulfill a considerable portion of a nation's public transit requirements. Significant findings emphasize that electric buses showcase considerably lower emissions than fossil-fuel-driven counterparts, especially when operated with zero-carbon electricity sources, thereby significantly mitigating the perils of climate change. [ABSTRACT FROM AUTHOR]

This paper presents an analysis of the cost of utilising Electric Vehicle (EV) batteries as energy storage in power grids (also known as Vehicle-to-grid, V2G) associated with lessening battery cycle life due to more frequent charging and discharging activities and utilisation in elevated ambient temperature. Comparison is made between V2G in the UK, where annual electricity peak demand is reached in winter, and in China, where peak demand is reached in summer due to the air conditioning load. Following an introduction on the mechanisms of battery aging and wear in V2G, the paper presents mathematical correlations between charging-recharging, ambient temperature, depth of discharge (DoD) and the degradation of electric vehicle batteries based on manufacturer's data. Simulation studies were carried out based on a 30-node sample electrical distribution network. Numerical results show that ambient temperature and DoD of an EV battery play a crucial role in the cost of battery wear. The annual cost of V2G for lead-acid and lithium-ion batteries' cycle life in China are roughly three times and twice, respectively that of the UK. The lead-acid battery is not cost-effective for V2G use according to the present electricity tariff however the use of the lithium-ion battery shows more favourable results due to the much longer cycle life. [ABSTRACT FROM AUTHOR]

Tesla recently introduced its Powerwall line of batteries, aimed at a sector of housing with solar electricity installed. This paper considers the economics behind mass introduction of batteries in the housing sector in the UK from the perspective of peak demand management. Utilities use differential tariffs (such as the Economy 7 tariff on Southern Electric in the UK) to encourage more homogeneous loads. Given current costs of battery systems, this work considers the rates of return that may be possible by buying electricity from the grid in times of low demand, and reselling at peak demand from the perspective of an average UK household. We consider the regulatory framework that would have to be in place to make this feasible and look at the effect a mass uptake of battery technology would have on peak demand management in the UK scenario. Overall however, it is found to not be economically feasible at current prices without heavy government subsidies. [ABSTRACT FROM AUTHOR]

This paper examines the impact of geographical location on the energy consumption of double deck battery electric buses operating in four UK cities. By considering seasonal variation in ambient temperature and an assumed battery degradation process, the implications on operational cost and carbon emissions were investigated. Using a MATLAB/Simulink model the total energy demand of a vehicle operating on the UKBC was simulated. Energy consumption was combined with hourly seasonal averages of carbon intensity (gCO 2 /kWh) and wholesale electricity costs (£) to assess charging at different times of the day and year. At the beginning of life, the range could decrease by up to 17.3% due to heating load requirements. From beginning of life to end of life, range was predicted to decrease by up to 26%. Whilst the average operational costs are relatively consistent across the four regions, the average carbon emissions can be five times higher depending on location. [ABSTRACT FROM AUTHOR]

This paper was inspired to answer the fundamental question on whether electric battery powered ships can ultimately be a promising solution for future maritime environmental protection. The overall process was designed to demystify the holistic environmental benefits and harms of 14 primary energy sources for electricity production in consideration of the national-specific cases of 33 countries. A series of comparative analyses between the diesel as the reference fuel and the battery-electric propulsions were conducted with 27 short-route ferries engaged in Scotland coastal areas. A key message obtained from the analysis results were that the impact of battery application was far from the zero-emission shipping in the lifecycle perspective. Moreover, the same vessels were found to yield completely different environmental performances, depending on how those countries produce electricity. In some Asian countries heavily relying on fossil-based power generation, the environmental impact of battery operation was estimated far greater than that of diesel operation in the UK. Case studies were, then, scaled-up to about 5500 marine vessels presently engaged in international voyages. In general, consistent results were found. Research findings distinctively demonstrated the misguidance of current maritime policies for encouraging battery-powered ships and identified that these shortcomings would stem from the limitations of current practices of maritime environmental assessment. Lastly, it strongly suggested to the marine industry and stakeholders that the environmental protection from shipping activities would be not only a matter of ships but also a matter of how the national power grid develops. • Lifecycle environmental benefits/harms of hybrid ships were demystified. • Underlying parameters for ship environmental performance were identified. • Corrective actions were proposed for proper use of electric ship propulsion. [ABSTRACT FROM AUTHOR]

• V2G can reduce peak demand up to 40% further than unidirectional smart charging. • Both charging losses and resistive network losses increase as a result. • The benefit of V2G is largest when around 20% of households on a network have an EV. • Solar generation on the network significantly increases its value. In recent years, there has been growing interest in AC vehicle-to-grid charging in residential networks. Bi-directional smart charging offers additional flexibility compared to uni-directional smart chargers, but are expensive to install and implement. This paper investigates the costs and benefits to the distribution network that bi-directional charging provides, relative to uni-directional charging. Benefit is quantified in terms of the reduction in the peak demand of the network, and costs are quantified with the increase in throughput of the vehicles' batteries and the increase in electrical losses in the system. Measured data and representative networks are used to construct two representative case studies of residential charging, one in the UK and one in Texas, US. [ABSTRACT FROM AUTHOR]

The article offers information on ingestion of button batteries by children. In the years 2013 and 2014, four toddlers died in Great Britain died after ingestion of button batteries. Serious burns take place because of generation of electric current which hydrolyses tissue fluids and creates hydroxide at the negative pole of the battery.