1,721,035 research outputs found
Renewable Energy Communities as an Enabling Framework to Boost Flexibility and Promote the Energy Transition
No full textUndelayable environmental requirements and the energy crisis following the pandemic, further increased by international contingencies, have evidenced the need to push forward with the energy transition and intensify the use of renewable energy to satisfy energy needs, with more flexible, resilient, and sustainable energy being required [...
Real-Time Control of Renewable Community Energy Resources Including Demand Response Providers
No full textThis paper proposes a tool for the optimal real-time management of the resources of a renewable energy community. According to Italian Regulations, the renewable energy community members are fed by distribution networks connected to the upstream high-voltage network through the same substation. The community includes renewable energy systems, battery energy storage systems, and controllable and non-controllable loads. The proposed approach implements the optimal operation within a probabilistic framework and is aimed at maximising the community's shared energy, providing demand response to the distribution network, and providing available capacity for delivering services to the distribution grid and/or to the upstream grid. Numerical applications allow testing of the proposed real-time control tool showing its potential in terms of monitoring and control of the resources and of the required services
Environmental and economic issues for the sizing of battery energy storage combined with renewable generation in an industrial facility
No full textThis paper analyzes the inclusion of a battery energy storage system equipping a photovoltaic generation system in an industrial facility. The main objective of the analysis is the evaluation of the economic and environmental implications related to the design choices. Besides the economic viability evaluation, two indices have been used for the analysis, namely the self-consumption rate and self-sufficiency rate, which allowed evaluating the ability of the system to reduce energy request to the grid. As an economic indicator, a modification of the levelized cost of use index is proposed and its application on a prosumer facility is consider so assessing also the benefit derived from selling energy to the grid. A total cost analysis has been carried out in order to discuss the optimal battery sizing solution
Caputo derivative applied to very short time photovoltaic power forecasting
No full textIntra-hour photovoltaic power forecasting provides essential information for real time optimal control of microgrids. At this purpose, a critical issue is the selection of the forecasting method. The choice of a forecasting method depends on many factors such as the availability of historical data, the time horizon, the lag period, and the time available for the forecast. Persistence based methods are particularly tailored for real time forecasting which require fast information and are typically a good trade-off choice when dealing with real time operation of microgrids. Their accuracy, however, could be not satisfactory in some cases such as when it appears critical to consider the trend of the power output in the last few minutes rather than only the last measured value. Derivatives help reach this goal, but fractional derivatives seem to be a more accurate choice in order to take into account the history of the variable to be forecasted as they are a promising tool for describing memory phenomena. In this paper, a novel intra-hour forecasting method is proposed based on the Caputo derivative. Numerical applications are carried out to show the efficacy of the proposed approach. Also, the accuracy of the proposed approach is tested through comparison with three models namely, persistence, derivative-persistence and auto regressive moving average models. The strength of the proposed forecasting tool is strictly related to its low computational burden without compromising accuracy. This makes of it an interesting means for real time grid operation strategies and can be of interest for the grid operators especially in vision of the changes distribution grids are witnessing with the transition to the smart grid paradigm
Surge arrester optimal placement in distribution networks: A decision theory-based approach
No full textThe study introduces a novel method for optimizing surge arrester placement in the distribution line to mitigate lightning-induced overvoltages, employing a single-objective optimization algorithm. The study assesses the effectiveness of two types of surge arresters concerning discharge energy in reducing lightning overvoltage. Moreover, the comparative analysis takes into account the transfer of overvoltage performance from protected to unprotected towers, highlighting its significance in estimating flashover rates under different protection alternatives. Decision theory analysis is employed in the present study to identify optimal arrester locations. The study aims to minimize the expected flashover rate and identify the most effective protection strategy by considering futures/scenarios associated with different values of peak current and lightning locations. The results of numerical applications also showed the substantial impact of lightning surge transfer within the network, emphasizing the imperative to incorporate this phenomenon into lightning protection modelling
Contribution of Renewable Energy Communities to Grid Operation: Sensitivity and Statistical Analyses
No full textThis paper deals with renewable energy communities including energy storage systems, controllable and non-controllable loads, and electrolyzers for hydrogen production. The community's resources are connected to different nodes of a distribution network and their contribution to network operation is analysed. The resources provide flexibility services to the grid in terms of demand response and reactive power support and optimize their operation by maximizing their economic benefits. Uncertainties due to renewable energy production and load demand strictly affect the obtainable economic benefit of the community members and the operation of the distribution network. For this reason, this paper proposes an analysis concerning community resource configuration and uncertain operation scenarios. Particularly, community self-consumption performance including hydrogen production potential is analyzed within the Italian incentive scheme
Probabilistic planning of a battery energy storage system in a hybrid microgrid based on the Taguchi arrays
No full textThe transformation of electrical networks in the context of the new smart grid paradigm unavoidably involves new challenges for electrical component planning. This paper provides a tool for the probabilistic sizing of a battery energy storage system in a hybrid AC/DC microgrid (i.e., a microgrid including AC and DC subsections with AC and DC loads and renewable power generation). The procedure is based on an analytical formulation to assess the total costs sustained by the microgrid for the inclusion of the battery energy storage system. The total costs depend on the random nature of the load demand, the electrical energy prices, and the renewable power generation, therefore, a probabilistic approach has been used. Furthermore, to account for uncertainties that affect the input data, the Taguchi orthogonal arrays are applied which allow significantly reducing the computational efforts while guaranteeing the desired accuracy of the results. The proposed analytical formulation along with the use of the Taguchi orthogonal arrays allows limiting the computational complexity even in presence of a large number of random inputs and discretization levels. A case study based on an industrial hybrid microgrid is presented to analyse the results obtained in terms of the optimal sizing of the battery energy storage system and to investigate the sensitivity with respect to some inputs
Electrical Energy Storage in a Renewable Energy Community: a Planning Approach
No full textRenewable energy communities are an important means to encourage the participation of citizens in the energy transition. The ownership of generation plants by the community citizens allows for lowering investments and thus energy costs, as well as increasing decentralized power plants at the local level. Also, sector-coupling energy services within a community, such as charging/discharging of electric vehicles, allow for providing flexibility services to the power system. In this framework, electrical energy storage systems have a central role. High shares of renewable energy imply the need to store electricity due to the variability of the energy source. Also, the use of electrical energy storage in electric vehicles or total renewable microgrids represent a step forward to decarbonizing systems that were heavily reliant on fossil fuel. From the end-user point of view, consumers can reduce their electricity bills, lowering peak demand charges as well as increasing self-consumption. In this context, the planning of energy storage systems for an energy community is a critical task which needs to be dealt with considering the regulatory framework. In this paper, a planning approach is proposed for optimally sizing both the storage and photovoltaic system in an energy community considering the incentive mechanism which is applied with reference to the shared community energy. The proposed approach properly accounts for a probabilistic characterization of the variables affecting the charging/discharging of storage systems, such as demand and renewable energy production. A case study referring to the Italian regulatory framework is proposed
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