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The Renewable Energy Directive II introduces renewable energy communities, enhancing energy sharing. However, many existing initiatives, focussing only on electricity, overlook the substantial energy demand in building sector comprising residential and commercial spaces. Energy communities in this sector can leverage district heating and cooling technology for thermal energy sharing, contributing to carbon neutrality by enhancing efficiency and reducing primary energy usage. Advanced strategies such as integrating renewables into heating and cooling grids, sector coupling, and utilising waste heat are key in moving away from fossil fuels. The Campania Region (Italy), abundant in geothermal energy potential, chose a district in which to implement the GeoGRID system. This innovative setup combines a four-pipe district heating and cooling network with an Organic Rankine Cycle plant, tapping into geothermal energy from the Solfatara area. The geothermal fluid's heat feeds the ORC evaporator and then powers the thermal network, allowing direct heating and domestic hot water supply during winter. A thorough techno-economic analysis assessed the energy potential extractable from the geothermal fluid. Crucial aspects of this study are the evaluation of the energy and environmental efficiency of the system within the renewable energy community framework. Additionally, the paper introduces a methodology applicable for assessing geothermal energy communities on a global scale. [ABSTRACT FROM AUTHOR]

Amid escalating energy demands and growing environmental concerns, educational institutions are transforming into crucibles for enduring innovation. This comprehensive review summarizes the complex relationship between Energy Efficiency and Renewable Energy Systems (EERES) within the sphere of educational institutions. By instituting Energy Efficiency initiatives, organizations can curtail energy consumption, resulting in substantial cost savings and a diminished carbon footprint. Moreover, the integration of renewable energy technologies empowers the localized generation of electricity, ensuring a reliable and sustainable energy source. Noteworthy in this study is the novel linkage of energy usage indicators to the comfort levels experienced in university settings during both summer and winter. An exhaustive examination of consumption indicators, rooted in the diverse activities on college campuses, further enriches the investigation. Beyond technical intricacies, this study scrutinizes the economic viability, environmental advantages, and educational significance of these integrated systems. Embracing EERES not only aligns with the commitment of educational institutions to environmental stewardship but also establishes a paradigm for broader communities. These institutions aspire to exemplify sustainable practices, influencing larger societal behavior positively. Various factors, including the institution's type, energy source, facility nature, building construction, internal activities, weather conditions, and user behavior, wield substantial influence over energy utilization. This study offers a nuanced exploration, shedding light not only on the technical dimensions but also on the broader economic, environmental, and educational implications of adopting EERES. [ABSTRACT FROM AUTHOR]

Renewable energy communities are catalysts of social innovation, the citizens' engagement in energy actions, and the exploitation of local resources. Thus, this paper defines a model for analyzing and optimally sizing energy systems serving renewable energy communities. Then, the proposed and replicable model was tailored to the economic feasibility analysis of a renewable energy community in the municipality of Tirano (Northern Italy). An energy audit was carried out to identify the electricity production and consumption within the perimeter of the primary substation and the thermal energy demand of the existing district heating network. The technical features of the energy conversion systems serving the renewable energy community were determined: an organic Rankine cycle biomass-based cogeneration plant, a mini-hydro plant, and a distributed photovoltaic system. Moreover, several different scenarios have been identified, in terms of cogeneration operating mode, photovoltaic penetration, and thermal energy economic value. The results show that, moving from 4.22 MW to 5.22 MW of photovoltaic peak power, the annual renewable electricity production increases by 10.1%. In particular, the simple pay back ranges between 4.90 and 4.98 years and the net present value between EUR 12.4 and 13.3 M for CHP operating at full power mode, considering that thermal energy available from the cogeneration unit is sold at EUR 49.2/MWh. These outcomes demonstrate the economic feasibility of wood-biomass-based renewable energy communities, which may help to enlarge the contribution of renewable technologies other than photovoltaic. [ABSTRACT FROM AUTHOR]

Recent European Directives have promoted Renewable Energy Communities as pivotal drivers to achieve energy and environmental European targets. In this context, the aim of this paper is to assess the energy and environmental feasibility of a Renewable Energy Community located in Northern Italy. The analysis is conducted starting from the real electricity consumption and thermal energy requests data made available from different datasets. After the analysis and processing of input data, the size and technical characteristics of the devices installed at the Renewable Energy Community are defined. A biomass-based cogenerator, a small hydro power plant, and distributed photovoltaic systems have been selected, thereby different layouts are considered and analysed, in terms of cogenerator operating mode and photovoltaic systems peak power. The results show that, in the best scenario, the annual renewable electricity used to satisfy electric load increases by 20.3% and about 68.1% of the total thermo-electric requests are met through biomass utilization. The bi-directional interactions with power grid are reduced from 60.6% to 51.7%. The thermal and electric sharing within the community ensures a decrease of carbon dioxide emissions up to 18.5%. • Analysis of energy systems serving district heating network at Tirano municipality. • Characterization of thermal and electric loads with 1-h granularity. • Modelling and simulation of most suitable Renewable Energy Community layouts. • Definition and evaluation of energy and environmental key performance indicators. [ABSTRACT FROM AUTHOR]

Gas engine-driven heat pumps are an interesting option to satisfy space heating and cooling demands aiming at energy saving, environmental impact and operating costs' reduction. This work presents (i) a comprehensive review updated on gas engine-driven heat pumps research activities, (ii) the investigation of the central role of this technology in the air conditioning sector and (iii) the future perspectives regarding gas engine heat pumps' diffusion in the context of the energy sector decarbonisation. The outcomes highlight that gas engine heat pumps could have better environmental performance compared to electric heat pumps both in heating and cooling operations. Moreover, they could play a pivotal role in the fight against climate change and energy security since they can guarantee an energy mix differentiation moving from electricity to natural gas and renewable gases' usage. Indeed, by 2030, a lower-carbon gas grid could be supported by renewable gases. A further investigation has concerned diffusion of gas heat pumps activated from biofuels produced by local biomass in an energy community scenario based on a low-temperature energy district network. A novel biomass-based GEHP interacting with a low-temperature district heating network is proposed here. This system could save more than 30% of primary energy compared to biomass-fuelled boilers. [ABSTRACT FROM AUTHOR]

Cogeneration and trigeneration systems can contribute to the reduction of primary energy consumption and greenhouse gas emissions in residential and tertiary sectors, by reducing fossil fuels demand and grid losses with respect to conventional systems. To evaluate the performance of these systems, several indices and assessment methodologies can be used, due to the high complexity of such systems, which can consist of several energy conversion devices and can perform bidirectional interactions with external electric and thermal grids. In this paper, a review of the available indices and methodologies to assess the performances of polygeneration systems is provided. An index ( TSS tri ) aimed to assess the economic feasibility of a trigeneration system is also introduced and discussed. This activity started in the framework of the International Energy Agency Annex 54 project (“Integration of Micro-Generation and Related Energy Technologies in Buildings”), where research groups shared their expertise about methods applied in each Country to evaluate the performance of polygeneration systems. It was concluded that a thermo-economic analysis comparing the performance of a polygeneration system with those of a reference benchmark scenario, is a very suitable assessment method. Some of the reviewed methodologies are then applied to small scale commercial cogenerators. The sensitivity analysis is performed considering different reference average values of electric efficiency, unitary natural gas and electricity prices, and emission factors for some European Countries. [ABSTRACT FROM AUTHOR]