• Energy Research

During an extraordinary event, like the COVID19 pandemic, very rapid changes in consumption profiles and customers behaviors were recorded. This paper investigates the impact of the lockdown on load and production in the distribution system of Terni. From a DSO point of view, no relevant issues were encountered to be faced. The distributed power generation from renewable resources did not affect relevant issues, maintaining the typical annual generation profiles. A domestic consumption increase was replaced by more relevant decrease of industrial processes and commercial activities absorptions. More than 25,000 domestic users increased their consumptions in April 2020 and the overall consumption of domestic customers in March was 1,05 times higher than the 2015 respectively consumption. The power flows at primary substations reveal a relevant electric demand reduction for each point of connection with the high voltage transmission system; especially bar 1 and 2 of the most relevant Terni primary substation, recorded a 15.3% decrease with respect to March 2019, and a 24.25% decrease with respect to April 2019.

Large-scale deployment of renewable energy sources brings new challenges for smart grid management requiring the development of decentralized solutions and active participation of prosumer and non-grid-owned assets. Local energy flexibility markets can help in monitoring energy flows, motivate changes in prosumers’ energy supply and demand, achieving local energy balance, and optimization of electricity flows. In this paper, we propose a blockchain-based decentralized energy flexibility market enabling small-scale prosumers to trade in a peer-to-peer fashion their flexibility in terms of load modulation concerning the baseline energy profiles. We have defined an energy flexibility token for digitizing the flexibility of prosumers allowing to be traded on the market as an asset and self-enforcing smart contracts for decentralized market operation including functions such as the placement of flexibility bids/offers, trading session management, or energy and financial settlement of energy flexibility transactions. For matching the flexibility bids and offers, a solution based on a greedy heuristic and a bipartite graph is proposed for minimizing the number of flexibility transactions and reducing the blockchain-associated costs, while Oracles are used to assure its secure integration with the blockchain. The blockchain-based flexibility market was validated with the help of the Terni city Distribution System Operator, showing promising results in enabling the self-consumption of renewable energy generated in a small scale urban micro-grid considering live energy monitoring data, and in assuring the local balancing of the demand side in a simulated environment considering many market participants and historical energy data.

The paper presents a feasibility study regarding the ability of an existing rural microgrid to supply an islanded portion of the MV distribution network. The microgrid is currently off-grid, but in the near future will be connected to the MV distribution grid. Based on load and generation measurements in a six-month period, a statistical analysis is carried out with the aim to check the ability of the microgrid to guarantee such a service whenever requested. Steady state simulations, also taking into account a proposed control strategy of the microgrid energy resources during islanding operation, show that for a significant share of cases the islanding operation is feasible.

Over the past few decades, industry and academia have made great strides to improve aspects related with optimal energy management. These include better ways for efficient energy asset management, generating great opportunities for optimization of energy distribution, discomfort minimization, energy production, cost reduction and more. This paper proposes a framework for a multi-objective analysis, acting as a novel tool that offers responses for optimal energy management through a decision support system. The novelty is in the structure of the methodology, since it considers two distinct optimization problems for two actors, consumers and aggregators, with solution being able to completely or partly interact with the other one is in the form of a demand response signal exchange. The overall optimization is formulated by a bi-objective optimization problem for the consumer side, aiming at cost minimization and discomfort reduction, and a single objective optimization problem for the aggregator side aiming at cost minimization. The framework consists of three architectural layers, namely, the consumer, aggregator and decision support system (DSS), forming a tri-layer optimization framework with multiple interacting objects, such as objective functions, variables, constants and constraints. The DSS layer is responsible for decision support by forecasting the day-ahead energy management requirements. The main purpose of this study is to achieve optimal management of energy resources, considering both aggregator and consumer preferences and goals, whilst abiding with real-world system constraints. This is conducted through detailed simulations using real data from a pilot, that is part of Terni Distribution System portfolio.

The energy transition requires an increasing penetration of renewable resources, particularly at MV/LV levels. The emerging production scheme is char- acterized by distributed power plants, imposes a capillary control of production and consumption among the distribution network (DN). The implementation of demand- side response (DSR) campaigns is widely seen as a solution that can increase grid stability, but they require a complex and expensive monitoring infrastructure to select the optimal operating point of the production/consumption systems. This paper suggests a cheap and reliable smart monitoring device based on Raspberry Pi tech- nology. The communication infrastructure adopted in the smart building of ASM S.p.A., the distribution system operator (DSO) of Terni city, shows the feasibility of implementing this prototype on a large scale.

The paper presents a technical/economic feasibility study of the adequacy of a 100% renewable power system. The study relies on a hybrid nodal/zonal linear DCOPF formulation, developed by the authors in order to study years-long time frames of power system operation on an hourly basis. The formulation sizes and operates a 100% renewable generation mix amongst the most widely used sources, such as pumped storage hydro, photovoltaic (PV), wind and biomass plants, also including electrochemical batteries (BESSs) as a further storage option. An existing medium scale power system, namely the 400/230/150 kV Sardinian transmission system, is the realistic case study. Technical/economic feasibility is investigated by means of the proposed formulation for different scenarios and operational insights are also provided.

The paper investigates the installation of energy storage systems (ESS) for a 3kV DC railway line located in the North of Italy. The main goals are to compensate voltage drops along the line and to regulate the system's voltage and to recover braking energy of trains. Electromechanical performances of trains and electrical system operation have been simulated by means of a software in order to evaluate the power demand of each train, the TPSSs (Traction Power Substations) power profile and voltage trend along the line, as well as the energy recovery and ESSs installation benefits. Two technological solutions regarding the design of ESS are described and simulated: lithium batteries and supercapacitors storage systems. The first solution is suggested due to the cost savings and the smaller requirements in terms of space occupation and total weight, while the second solution is suggested in case of great power and due to low levels of maintenance The analysis shows the benefits of the implementation of each type of ESS.