Optimal operation planning of Distributed Energy Systems through multi-objective approach: a new sustainability-oriented pathway

The energy system is an essential part of nowadays society. The concept of “energy system” commonly refers to the energy-supply chain as the whole system consisting of the energy conversion devices as well as storage units from the energy resources to the final user demands. In the 1900’s, energy has been commonly provided by large generation power plants operating in a central location and transmitted to consumers via transmission and distribution networks. In a typical centralized energy system, a large number of end-users is located within a large area. A Distributed Energy System (DES) can be regarded as the opposite of a centralized energy system, where the term “distributed” illustrates how single energy conversion devices and storage units are integrated into the whole energy system. Therefore, a DES refers to an energy system, where energy is made available close to energy consumers, typically relying on a number of small-scale technologies. In recent years, developing DESs has attracted much interest, since these systems have been recognized as a sustainability-oriented alternative to conventional centralized energy systems. In general, sustainability means an equitable distribution of the limited resources and opportunities in the context of the economy, the society, and the environment, aiming at the well-being of everyone, now and in future, thereby guaranteeing that needs of future generations may be completely satisfied as happens today. One of the main benefits of DESs is the possibility to integrate different energy resources, including renewable ones, as well as to recover waste heat from power generation plants for thermal purposes. This benefit allows to enhance sustainability of the energy supply through a more efficient use of the energy resources as well as a reduced environmental impact, as compared with conventional energy supply systems. Through an appropriate planning, DESs may exhibit even better performances than a single polygeneration system, such as Combined Cooling Heating and Power systems or conventional energy supply systems. The optimal planning of DESs is not a trivial task, as integration of different types of energy resources and energy conversion devices as well as storage units may increase the complexity of the system. Moreover, generally different stakeholders participate in DESs development and management. Hence, objectives can be defined from different perspectives, such as the developers and operators of DESs, or the civil society, ideally represented by the regulator. Some of the DESs planning objectives are naturally conflicting. Consequently, there is not a single planning solution, which can satisfy all the stakeholders. For instance, society interest in sustainable energy supply systems, and with low environmental impacts, might conflict with the economic interest of the developers and operators of DESs. A multi-objective approach helps to identify compromise solutions, which benefit all the stakeholders. This thesis presents an original tool based on a mathematical programming approach, to attain the optimal operation planning of DESs through multi-objective criteria, by considering both short- and long-run priorities. Multi-objective optimization problems are formulated to find the optimized operation strategies of DESs in order to take into account short-run priorities characterized by the crucial economic factor, as well as long-run priorities in terms of sustainability. This latter is attained through exergy concepts as well as environmental impacts assessments

experimental validation of a tool for the numerical simulation of a commercial hot water storage tank

Abstract This work focuses on the experimental validation of a numerical tool realized to simulate a commercial hot water storage tank. The tool implements unsteady 1D models to simulate the temporal evolution of the temperature field inside the hot water storage tank, and the one relative to the heat transfer fluid flowing through the immersed coil heat exchanger. It has been implemented by means of the Simulink tool of Matlab. The first part of the paper is dedicated to the description of the indoor experimental facility used to realize the experimental test. Successively, the analytical models, and the numerical schemes and algorithms used to perform the numerical simulations are described. Finally, the results of the experimental validation of the tool, accomplished by comparing the experimental temperature profiles inside the tank, and the measured temperatures at the coil heat exchanger exit section over the entire experimental test duration, with the numerical results obtained from simulations performed using different correlations for the evaluation of the heat transfer rate between the tank water and the heat transfer fluid through the coil, are reported and discussed

Development of Energy Communities in Europe

This paper presents a review study of energy communities (ECs) in Europe, and discusses the future development of such communities in Europe – both related to energy technologies, energy carriers, regional conditions (North, Central and South of Europe), emerging regulatory development etc. From the analysis, it emerged that the future ECs in Europe will focus on utilizing local renewable energy sources (sun, wind, run of river, biogas, biomass), for covering all or part of the energy consumption for end-use customers. The ECs can be a sustainable alternative to large power plants based on fossil fuels. This is also linked to the emerging regulatory developments started when European Commission introduced such concepts in the “Clean Energy for all Europeans” package. The main goal of eNeuron H2020 project is to develop innovative tools for the optimal design and operation of ECs, integrating distributed energy resources and multiple energy carriers at different scales.Development of Energy Communities in EuropeacceptedVersio

design optimization of a distributed energy system through cost and exergy assessments

Abstract In recent years, Distributed Energy Systems (DESs) have been recognized as a good option for sustainable development of future energy systems. With growing environmental concerns, design optimization of DESs through economic assessments only is not sufficient. To achieve long-run sustainability of energy supply, the key idea of this paper is to investigate exergy assessments in DES design optimization to attain rational use of energy resources while considering energy qualities of supply and demand. By using low-temperature sources for low-quality thermal demand, the waste of high-quality energy can be reduced, and the overall exergy efficiency can be increased. Based on a pre-established superstructure, the aim is to determine numbers and sizes of energy devices in the DES and the corresponding operation strategies. A multi-objective linear problem is formulated to reduce the total annual cost and increase the overall exergy efficiency. The Pareto frontier is found to provide different design options for planners based on economic and sustainability priorities, through minimizing a weighted-sum of the total annual cost and primary exergy input, by using branch-and-cut. Numerical results demonstrate that different optimized DES configurations can be found according to the two objectives. Moreover, results also show that the total annual cost and primary exergy input are reduced by 20% - 30% as compared with conventional energy supply systems

Management of renewable-based multi-energy microgrids in the presence of electric vehicles

This study proposes a stochastic optimisation programming for scheduling a microgrid (MG) considering multiple energy devices and the uncertain nature of renewable energy resources and parking lot‐based electric vehicles (EVs). Both thermal and electrical features of the multi‐energy system are modelled by considering combined heat and power generation, thermal energy storage, and auxiliary boilers. Also, price‐based and incentive‐based demand response (DR) programs are modelled in the proposed multi‐energy MG to manage a commercial complex including hospital, supermarket, strip mall, hotel and offices. Moreover, a linearised AC power flow is utilised to model the distribution system, including EVs. The feasibility of the proposed model is studied on a system based on real data of a commercial complex, and the integration of DR and EVs with multiple energy devices in an MG is investigated. The numerical studies show the high impact of EVs on the operation of the multi‐energy MGs.©2020 IET. This paper is a postprint of a paper submitted to and accepted for publication in IET Renewable Power Generation and is subject to Institution of Engineering and Technology Copyright. The copy of record is available at the IET Digital Library.fi=vertaisarvioitu|en=peerReviewed

A multi-objective optimization analysis to assess the potential economic and environmental benefits of distributed storage in district heating networks: a case study

Conventionally, district heating networks have been developed with a centralized logic, with large generation units designed to provide space heating to distributed users. Some networks have already evolved to a stage in which multiple generation units are distributed throughout the network and are supplying heat from different sources and with different schedules. ICT technologies can be the basis for a live optimization of the network, which can be implemented by minimizing energy supply cost for the users or minimizing greenhouse gases emissions. This paper presents an analysis of the potential effects of including distributed heat storage units to an existing DH network, as the first step toward opening the interaction with users. The results show the limited effect of the demand profile variation in comparison with the potential benefits of optimization strategies against the current operation of the case study under analysis, the main reason being the good flexibility of the available heat generation units. Thus, the installation of distributed storage units should be preferred in DH networks characterized by a large share of non-flexible generation options, such as solar energy or waste heat from industries, or where the energy prices show large variations over the day

Analysis of necessary evolution of the regulatory framework to enable the Web-of-Cells development : [ELECTRA]

Deliverable D3.3 discusses how the solutions proposed within ELECTRA can be tailored to the typical rules that will be imposed by national/EU regulators, and/or how the regulations can be extended or adapted to cover the new concepts developed in ELECTRA (Web-of-Cells architecture, associated control mechanisms, Cell System Operator role, etc.)

Posttraumatic growth (PTG) and posttraumatic depreciation (PTD) across ten countries: Global validation of the PTG-PTD theoretical model

info:eu-repo/semantics/publishedVersio