This paper investigates the possibility of charging battery electric vehicles at workplace in Netherlands using solar energy. Data from the Dutch Meteorological Institute is used to determine the optimal orientation of PV panels for maximum energy yield in the Netherlands. The seasonal and diurnal variation in solar insolation is analyzed to determine the energy availability for EV charging and the necessity for grid connection. Due to relatively low solar insolation in Netherlands, it has been determined that the power rating of the PV array can be oversized by 30% with respect to power rating of the converter. Various dynamic EV charging profiles are compared with an aim to minimize the grid dependency and to maximize the usage of solar power to directly charge the EV. Two scenarios are considered – one where the EVs have to be charged only on weekdays and the second case where EV have to be charged all 7days/week. A priority mechanism is proposed to facilitate the charging of multiple EV from a single EV–PV charger. The feasibility of integrating a local storage to the EV–PV charger to make it grid independent is evaluated. The optimal storage size that reduces the grid dependency by 25% is evaluated

Battery aging is one of the critical problems to be tackled in battery research, as it limits the power and energy capacity during the battery’s life. Therefore, optimizing the design of battery systems requires a good understanding of aging behavior. Due to their simplicity, empirical and semiempirical models (EMs) are frequently used in smart charging studies, feasibility studies, and cost analyses studies, among other uses. Unfortunately, these models are prone to significant estimation errors without appropriate knowledge of their inherent limitations and the interdependence between stress factors. This article presents a review of empirical and semiempirical modeling techniques and aging studies, focusing on the trends observed between different studies and highlighting the limitations and challenges of the various models. First, we summarize the main aging mechanisms in lithium-ion batteries. Next, empirical modeling techniques are reviewed, followed by the current challenges and future trends, and a conclusion. Our results indicate that the effect of stress factors is easily oversimplified, and their correlations are often not taken into account. The provided knowledge in this article can be used to evaluate the limitations of aging models and improve their accuracy for various applications.

Workplace charging of electric vehicles (EV) from photovoltaic (PV) panels installed on an office building can provide several benefits. This includes the local production and use of PV energy for charging the EV and making use of dynamic tariffs from the grid to schedule the energy exchange with the grid. The long parking time at the workplace provides the chance for the EV to support the grid via vehicle-to-grid technology, the use of a single EV charger for charging several EVs by multiplexing and the offer of ancillary services to the grid for up and down regulation. Further, distribution network constraints can be considered to limit the power and prevent the overloading of the grid. A single mixed integer linear programming (MILP) formulation that considers all the above applications has been proposed in this paper for a charging a fleet of EVs from PV. The MILP is implemented as a receding-horizon model predictive energy management system. Numerical simulations based on market and PV data in Austin, Texas have shown 32% to 651% reduction in the net cost of EV charging from PV when compared to immediate and average rate charging policies.

Charging electric vehicles (EVs) from photovoltaic panels (PV) provides a sustainable future for transportation. This paper presents the development of a 10kW EV charger that can be powered from both a PV array and the three phase AC grid. The goal is to realize a high power density and high-efficiency three-port power converter that integrates the EV, PV, grid and meets the Chademo and CCS/Combo EV charging standards. The EV port is designed to be isolated and bidirectional, so that both charging and vehicle-to-Grid (V2G) can be implemented. As PV and EV are both DC by nature, the converter uses a central DC-link to exchange power between the EV and PV, thereby increasing efficiency. The use of silicon carbide devices and powdered alloy core inductors enables high switching frequency and power density. A stable closed loop control allows four different power flows: PV- EV, EV-grid, grid-EV and PV-grid. Hence the converter operates as a PV inverter, a bidirectional EV charger and a combination of both. A 10kW prototype has been successfully tested and its experimental waveforms and measured efficiency are presented. It has three times the power density and higher partial and peak load efficiency when compared to existing solutions.

Microgrid with integrated photo-voltaics (PV) and battery storage system (BSS) is a promising technology for future residential applications. Optimally sizing the PV system and BSS can maximise self-sufficiency, grid relief, and at the same time can be cost-effective by exploiting tariff incentives. To that end, this paper presents a comprehensive optimisation model for the sizing of PV, battery, and grid converter for a dc microgrid system considering multiple objectives like energy autonomy, power autonomy, payback period, and capital costs. The proposed approach involves developing a holistic techno-economic microgrid model based on variables like PV system power, azimuth angle, battery size, converter ratings, capital investment and electricity tariffs. The proposed method is applied to determine the optimum capacity of a PV system and BSS for two case residential load profiles in the Netherlands and Texas, US to investigate the effect of meteorological conditions on the relative size of PV and battery. Based on the optimisation results, thumb rules for optimal system sizing are derived to facilitate microgrid design engineers during the initial design phase.

In recent years, the research interest in off-grid (standalone mode) and hybrid (capable of both standalone and grid-connected modes) charging systems for electric vehicles (EVs) has increased. The main reason is to provide a seamless charging infrastructure in urban and rural areas where the electrical grid is unreliable or unavailable so that EV adoption can be increased worldwide. In this regard, this article reviews the state-of-the-art architectures of the off-grid and hybrid charging systems and investigates their various subsystems, such as single or multiple energy sources, power electronics converters, energy storage systems, and energy management strategies. These subsystems should be optimally integrated and operated to achieve low-cost and efficient EV charging. Moreover, each subsystem is explored in detail to find the current status and technology trends. Furthermore, EV charging connectors, their power level, and standards for all kinds of EVs (ranging from one-wheeler to four-wheelers) are reviewed, and suggestions are discussed related to the non-standardization of charging plugs. Finally, conclusions show the continuous efforts of the researchers in improving the systems in various aspects, such as cost reduction, performance improvement, longevity, negative environmental effect, system size minimization, and efficient operation, and highlight challenges for both charging systems.