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Among different solutions to increase flexibility of electricity system, grid interactive water heaters (GIWHs) can make a large contribution, against a relatively low cost. They can advantageously be used within a single building, a local energy community or within an entire distribution grid, thanks to the very fast response time, low cost, highly distributed resource and widely demonstrated technology. In the near future, the flexibility potential of GIWHs will certainly increase, thanks to the advantageous flexibility programs that have been implementing in some area of the world, with the aim of coordinating several million of GIWHs with the electricity network. In this study, we assess the potential value that the flexibility of GIWHs can bring to the electrical power system, compared to the other sources of flexibility, focusing on the US market, specifically California, Oregon and Washington. The GIWH technology and the main GIWH control strategies are described, highlighting the flexibility behaviour of GIWHs. An overview of the GIWH pilot programs currently developed in the US market is provided, and current available technologies are shown, both for new and for retrofit GIWH installations. Most of the papers discussed in the literature focus on different aspects of demand response (DR), but very few of them focus specifically on GIWHs, and none of them offers a review of GIWHs in the US context. The present work thus constitutes a research gap, and could help stakeholders to assess the US GIWH market evolution, identifying the potential value of GIWH flexibility.

Renewable electricity for off-grid areas is widely seen as one of the top choices in supporting local economic development in most countries, and so is Vietnam. Over the years, many isolated networks using renewable energy sources have been deployed for off-grid areas in Vietnam. However, the use of these energy sources in Vietnam’s isolated networks is still facing many challenges due to its infancy here. The issues of reliability and vulnerability of these networks are not given the expected attention. Another challenge is that the issues of the operational security of these systems could also be negatively affected by the variable nature of renewable sources, including static and dynamic security. For this reason, this study aims to contribute to a better understanding of integrating renewable energy into isolated networks, and in this case, using solar power for the An-Binh Island grid in Vietnam. The findings from this study suggest that choosing the right structure of the power mix could contribute to improving the operational security of isolated networks. Moreover, several solutions to enhance the reliability of this grid are also proposed. The NEPLAN environment was selected for simulation and analysis for all the scenarios in this study.

The Blorin project started at the end of 2019 to support the implementation of a blockchain platform to support the energy services provision from end users by means of Demand Response and Vehicle to Grid programs. The experimental part of the project is being carried out on two Mediterranean islands and inside the University campus in Palermo. Customized smart contracts have been designed to support the active participation of end users to regulation services for the two weak electrical grids of the islands in the view of a deep penetration of renewable energy in the two energy systems. In particular, the smart contract for remuneration accounts for the very special energy situation of islands where TSO, DSO, energy seller and aggregator collapse in a unique market actor. Moreover, in islands the electricity provision is typically still relying on diesel generators thus strongly connecting the Demand Response programs benefit to the reduction of fuel consumption, as an effect of increased efficiency of diesel generators. Due to the critical international situation and to the climate crisis, fossil fuels get more and more costly, thus a speed up of the energy transition in small islands is highly needed. This paper addresses the problem of designing a customized smart contract for remuneration of Demand Response service provision in small islands.

Issues related to the stability of non-interconnected grids are of high relevance given the increasing presence of renewable sources in the power generation system. In order to ensure adequate levels of system's reliability, it is necessary to find new methods to ensure the stability of the electric grid. The present work proposes a methodology for the definition of the minimum number of Vehicle-to-Grid (V2G) charging points that would allow the integration of 1 MW of photovoltaic power in the power grid of the Italian island of Favignana, electrically disconnected from the continental grid. Primary frequency regulation simulations are carried out in Matlab/Simulink environment for different scenarios related to the generation park. The results show that with a limited number of V2G points levels of stability of the electrical system comparable to those before the installation of the photovoltaic plants can be ensured.

The Directive (EU) 2018/2001 (RED II) requires Member States to authorize the constitution of consumers as self-consumers of renewable electricity by ensuring them non-discriminatory and disproportionate treatment. Member States must establish a favorable framework for promoting and facilitating the development of self-consumption, including in collective form (art. 21). According to the Directive, the granting of rights to renewable energy self-consumers who act collectively allows to increase the energy efficiency of households and helps to combat energy poverty by reducing consumption and supply tariffs. In Italy, the decree n. 162/2019 and then amended with Decree 199/2021 has partially enacted the RED II Directive. On the other hand, it must be observed that after more than 2 years the number of energy communities in Italy is still limited. One of the main barriers is related to the fact that there is no clear indication about how to share the incentive among the REC's members. In this paper, an effective model for the remuneration of the energy community members is proposed and an experiment is carried out in a laboratory environment, supported by Prycam Home devices.

Transport sector is moving towards clean and green transportation with the growing market of electric vehicles globally. Electric vehicles are independent fossil fuels consumption, but the massive adoption of electric vehicles soon can lead to a significant burden on the power distribution networks. In this paper, a study on the potential impact of electric vehicles on the power distribution networks of two different regions with totally different realities of population density, an average number of cars per inhabitant, and travel habits has been carried out. The first region is the island of Favignana having an insular power distribution network, while the other region, the city of Palermo has a grid-connected power distribution network with eight substations. The load profiles of these two regions have been analyzed in detail with future scenarios of 10, 20, and 50 % penetration levels of electric vehicles. The Monte Carlo method having the capability of generating data on the behavior of car owners with consideration of different scenarios has been used, utilizing MATLAB software. The simulation results indicate that the high penetration levels of electric vehicles in the future will lead to high peak load demands and these results will be more severe for the regions having high population densities, a high average of cars per inhabitant, and long driving distances.

Vietnam became the world’s third largest market for solar photovoltaic energy in 2020. Especially after the Vietnamese government issued feed-in tariffs for grid-connected solar photovoltaic systems, the installed capacity of solar photovoltaic applications exploded in 2019. From studies carried out in the relevant literature, it can be said that support policies are highly important for the initial development of the renewable energy industry in most countries. This is especially true in emerging countries such as Vietnam. This paper reviews the feed-in tariffs issued and deployed in different regions of Vietnam for grid-connected solar photovoltaic applications. Moreover, the paper takes a closer look at the costs of electricity production from these systems in relation to the feed-in tariffs issued in Vietnam. The results show that the gap between the levelized cost of electricity and the feed-in tariff for solar photovoltaic electricity is relatively high, particularly in regions with a lower irradiation potential.

The new European Directive RED-II on the promotion of the use of renewable energy sources has introduced the concept of the Renewable Energy Community. This new entity has the potential to change the relations among end-users and the latter and the other actors of the energy sector. In particular, the electrical sector appears the most influenced by the implementation of this paradigm. Indeed, the need for self-consumption and for exploiting the full potential of renewable energy in a Renewable Energy Community influences how the end-users exchange energy with the power grid, the rules for their connection to the grid, the implementation of Demand Response and other energy management programs. For this reason, after a review of the existing legal framework, this paper investigates various aspects concerning the interaction of Renewable Energy Communities with the power system, highlighting what issues must still be addressed for a complete implementation of Renewable Energy Communities and their integration in the power system, with a focus on the Italian context.

The energy transition and climate neutrality are a short time scenario as climate concerns are rising fast. Small islands are natural microgrids in which the energy transition is subjected to economic and regulatory constraints and highly challenged by technical issues. As a first step, the Mediterranean island of Favignana has been considered in this study, to assess how electric mobility could impact the power system. According to the plans from the local decision makers, the island is moving towards a full public electric mobility in the near term, also due to the participation in the BloRin project. For this reason, a feasibility study about the technical and environmental impact of electric mobility is highly needed. What appears is that the network is ready for such a transition even if carried out in massive terms, while the current electric mix makes the shift to electric mobility more polluting. Therefore, the assessment of the environmental impact, quantified comparing the emissions of the current scenario with those of a future condition with a 20% penetration of EVs on the island, highlights the need of a simultaneous shift to zero emission power production. The simulations are carried out using the NEPLAN software and considering various operating scenarios. In most cases, the substations are charged two times the current power flows, but never going beyond the rated capacity.