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Time-of-use (TOU) energy cost management involves the use of energy storage systems (ESSs) by customers to reduce their electricity bills. The ESS is charged during off-peak time periods, when electricity energy prices are low, and discharged during times when on-peak energy prices are applied. This article addresses the question whether it is economically viable to install medium-scale distributed ESSs designed to lower the electricity cost for a customer-side application, assuming flexible electricity tariffs. The technical/economical evaluation is carried out referring to lithium-ion (Li-ion), sodium sulfur (NaS) and vanadium redox battery (VRB) technologies, performing a parametric analysis by changing the capital cost of the batteries and the difference between the maximum and minimum electricity price. A case study is performed to show the advantages/disadvantages of the proposed approach. The analysis reveals that, at the current costs of ESSs, the use of batteries for TOU applications is economically advantageous for a public institution facility in Italy only if there is a significant difference between the maximum and the minimum electricity price. The decrease in the cost of storage, stimulated by the implementation of support policies, will make ESS even more convenient for load shifting applications. [ABSTRACT FROM AUTHOR]

The paper focuses on the evaluation of the impact on residential buildings of innovative control logics defined for a rational utilization of the electric loads and air-conditioning systems. The control logics are implementable thanks to a Decision Support and Energy Management Systems developed by the same authors and easily installable in new and still-existing houses. The paper shows how a significant reduction of the primary energy consumption can be obtained by controlling the air-conditioning units together with the other electric loads of the house. After having explained how the control logics operate, a simulation tool is described, developed for a preliminary evaluation of their effects on the energy consumptions of residential buildings in the design stage. An application of the simulation tool on a typical house, considering different scenarios and varying the climatic conditions and the energy performance class of the envelope, is presented. Finally, a measurement campaign on two real existing houses, equipped with the Decision Support and Energy Management System, is described, and the effects of the control logics are assessed. [ABSTRACT FROM AUTHOR]

Tourist activity strongly influences the energy consumption and the overall load profile of communities with isolated energy systems. One example is hotel sectors on small islands that are not connected to mainland energy distribution grids. The use of solar energy systems could be a smart option for reducing energy consumption and tackling seasonal fluctuation. The operation of a weak and isolated electric grid requires attention to the management of power profiles in very short time frames. Energy storage (thermal or electric), as well as building automation control technologies, can be utilised for these aims. In this context, the present paper illustrates a study conducted at a hotel located on Lampedusa Island (Italy) that was considering some energy-retrofit scenarios dealing with the exploitation of renewable energy sources and building automation control technologies. The hotel is equipped with an air-to-water heat pump able to fulfil air conditioning and domestic hot water demands. Data concerning the hotel's energy consumption was measured during summer months while yearly data was provided by the local electric utility company. Detailed simulation models have been validated by this data and used to assess the efficacy of retrofit scenarios and their effects on the average daily electric profile. [ABSTRACT FROM AUTHOR]

Over the last decade, the architecture of the energy market has radically changed. In many countries end-users are now able to directly access the market, which has given rise to the question of how they can actively participate in that market. End-users can comprise a critical mass through aggregation that is carried out by a third party – to wit the “loads aggregator.” This paper proposes a new framework for generating feasible real-time price curves for those end-users in a demand-response management process. The underlying algorithm generates output curves as the solution to a constrained optimization problem whose objective function is the aggregator's economic benefit. A case simulation study of the Italian market, with various parameter options, illustrates the procedure. [ABSTRACT FROM AUTHOR]

The paper addresses the issue of the transition from a traditional electrical system without automation to a newer active and smart system allowing the possibility of implementing Demand Side Management policies, for little islands not supplied by the main grid. In particular, the paper focuses on two main topics related to the definition of: • an effective control, monitoring and communication system as a tool for the full exploitation of the opportunities given by Demand Response policies; • some solutions for the automation of the end-users’ electrical installations, in order to offer to the utility flexibility to be used for the improvement of the generation and distribution efficiency. After a brief discussion on the international regulatory framework on automation and ICT applications for power systems, the paper presents a feasibility study, based on the characteristics of the island of Lampedusa, of a hierarchical architecture of a suitable control system and of some DSM enabling solutions for residential end-users. The proposed solutions are defined taking into account some main elements: • distribution grids in small islands are generally equipped with outdated and hardly automatable devices; • utilities in small islands have reduced budget for new investments; • not less important, the most of the inhabitants has low income and unfamiliarity with automation. Therefore, main features of the proposed DSM enabling technologies are low cost and ease of use. [ABSTRACT FROM AUTHOR]