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Heat pump water heaters can increase the energy efficiency in sanitary hot water production, which is a relevant share of the final energy consumption in multiresidential and tertiary buildings. Refrigerants for these heat pumps are changing due to the F-Gas Regulation which bans high-GWP fluids. While CO 2 is an established solution, propane is a promising low-GWP alternative for heat pump water heaters serving large users in the tertiary sector, where refrigerant charge limits (due to propane's flammability) can be bypassed by installing the heat pump outdoors. Here, the components of a CO 2 and a propane air-water heat pump systems of 40 kW are sized and their COPs are compared in different climates; then, the two heat pumps are coupled to a storage tank and a user demand profile (hospital and school). For three different locations, tank size necessary to maintain users' comfort and seasonal performance factor are evaluated through simulation. [ABSTRACT FROM AUTHOR]

Electrical heat pumps for sanitary hot water production achieve a high performance with a good matching of water and refrigerant temperature profiles during the heat rejection stage, as it happens in CO 2 systems. This work considers the thermodynamic possibility to adapt the condenser pressure of a propane heat pump to maximize the COP, while producing sanitary hot water up to 60 °C from a heat sink equal to 15 or 25 °C. The performance of the heat pump is calculated through specific models which, in combination with a TRNSYS model of the whole system, allowed to assess its seasonal performance for a hotel in Strasbourg, also varying the control logic and the size of the storage tank. Results obtained led to the conclusion that, for achieving a high seasonal performance, the control logic of the tank has the largest influence. [ABSTRACT FROM AUTHOR]

• A Life Cycle Assessment of a recycling process for photovoltaic panels is performed. • The recovery of secondary raw materials (Al, Cu, Ag, Si, glass) is achieved. • The recovered glass is used in the manufacturing of building components. • The critical steps of the recycling process calling for improvement are identified. • The benefits of secondary materials recovery are compared to the process burdens. As a consequence of the photovoltaic (PV) market expansion in the last 20 years, the cumulative global PV waste is expected to exponentially grow. A proper disposal of decommissioned PV panels is crucial for avoiding environmental risks and for recovering value-added materials. In this study, a Life Cycle Assessment (LCA) was performed in order to assess the environmental performance of a new recycling process for crystalline silicon (c-Si) PV panels, at the End of Life (EoL). The process was developed in the framework of the ReSiELP (Recovery of Silicon and other materials from the End-of-Life Photovoltaic Panels) project, aiming at recovering valuable resources from EoL PV c-Si modules and making the recovered materials readily available for different supply chains, in line with the principles of Circular Economy. A "gate to gate" approach was used to investigate two lines of activities: (i) the Recovery line, dedicated to the recovery of secondary raw materials from EoL c-Si PV panels, namely aluminium, copper, glass, silver and silicon, and (ii) the Glass reuse line, for the employment of the recovered glass in prefabricated building components (predalles slabs). The results highlight energy consumption, chemicals and transportation as the main hotspots of the ReSiELP process. For a comprehensive evaluation, the generated loads were compared with the potential environmental benefits gained thanks to the recovery of aluminium, at the largest extent. Overall, the LCA analysis showed that the investigated process is environmentally favorable, also when compared to other EoL PV panels recycling scenarios reported in literature. [ABSTRACT FROM AUTHOR]