Energy: From ENEA a project to reduce energy consumption in smaller islands

Experimentation begins in Lampedusa at ENEA climate observatory

Reducing energy consumption in Italian small islands while protecting the environment, safety and housing comfort is the goal of the ENEA project conducted as part of the activities of the Electricity System Research program^[1] to promote energy efficiency as a tool for the decarbonization of the energy system.

"In small Mediterranean islands, hot water production and air conditioning have a significant impact on energy demand in the residential and tourism sectors. Recent studies^[2] have shown that about 40 percent of residential users' electricity consumption is attributable to hot water production, with significant peaks during the tourist season^[3]," explained Biagio Di Pietra, head of the ENEA Integrated Solutions for Energy Efficiency Laboratory. "Analyses conducted in Lampedusa together with the University of Palermo," Di Pietra said, "also showed that almost all residential users use electric water heaters.

To ensure complete self-sufficiency in domestic hot water production on small islands, an innovative hybrid system consisting of a small-scale photovoltaic system (1.74 kWp), a hybrid inverter, a heat pump with 200-liter storage, and a 3.6-kWh supercapacitor storage system were tested at the ENEA Climate Observatory in Lampedusa.

The goal of this experimental campaign is to determine the smaller size of the photovoltaic system coupled with the heat pump to obtain self-sufficiency of hot water production and the mix between electrical and thermal energy storage to make the entire process, from production to consumption, more efficient.

"In small island electricity grids, which are small in size, managing the intermittency of renewable power generation, as well as peaks in demand, is more complex" explained Francesco Baldi at the ENEA Integrated Solutions for Energy Efficiency Laboratory. "To overcome this problem, we used systems that automatically regulate the input of electrical generation to the grid, scheduling loads thanks to thermal storage and smart devices, controlled by the system and not by the user, who is still guaranteed maximum comfort."

The tests assessed the system's ability to efficiently produce hot water when needed, shifting electricity demand during peak production and minimizing exchange with the grid, with self-consumption values of 63 percent of the energy produced. The results highlighted some elements to be improved to adapt the system to existing installations and ensure replicability in similar contexts.

"Our research," Biagio Di Pietra said, "addresses additional issues: in collaboration with the University of Palermo, we have conducted an experimental study for a few years now at the Capo Grecale lighthouse in Lampedusa and the Pantelleria media library, aimed at testing free cool solar^[4] air conditioning systems. Finally, to empower citizens and businesses to take on active roles and benefit from the energy transformation, a series of training and dissemination activities have been organized in collaboration with local administrators, schools, electrical suppliers and researchers."

Research on innovative systems for domestic hot water production is just one of the activities carried out at the ENEA Climate Observatory in Lampedusa dedicated to study climate change in the Mediterranean region, a fragile area and climate hotspot.

Through participation in European research infrastructures and international networks, the measures implemented by the Observatory contribute to the development of mitigation and adaptation policies to limit damage from climate change. (https://www.lampedusa.enea.it).