Heating and cooling (H&C) accounts for approximately 50% of the European Union’s (EU) total energy demand and remains significantly reliant on imported fossil fuels. Hence, addressing the decarbonization of the H&C sector is key to achieving a successful energy transition. At the EU level, several legislative instruments within the Fit for 55 package directly target the decarbonization of H&C, including the core directives on renewable energy, energy efficiency, and the energy performance of buildings. At the national level, EU Member States (MSs) have developed National Energy and Climate Plans (NECPs), which are the main framework for defining national energy transition strategies, including measures to address H&C. Within the EU-funded REDI4HEAT project, a guideline was developed to support the assessment of policy documents—particularly NECPs—regarding the robustness of their policies and measures for decarbonizing H&C. This assessment framework supports the identification of gaps and opportunities through six key Strategic Policy Priority (SPP) areas, offering a set of policy options that can be further elaborated into effective measures. The design of these policy measures is informed by the Knowledge Sharing Centre—an online repository of replicable and adaptable initiatives that can be tailored to the specific geographical, social, and economic contexts of each MS.

Liquid desiccant dehumidification systems have been used for many years in specialized applications. The performance of liquid desiccant systems relies heavily on heat and mass transfer characteristics of two critical components: the dehumidifier and the regenerator. The purpose of this study is to provide a comprehensive review of heat and mass transfer correlations developed to mathematically model the adiabatic absorption and desorption process. There has been an attempt to describe the most important characteristics of each research, such as the method adopted, the assumptions used, validation of the data, as well as the most important results. It was found that most work considers the desiccant solution flowing counter currently with air and the use of structured packing instead of random. Fewer researchers considered co-flow configuration or desiccants other than salts.

This work provides the policy and economic analysis of the renewable heating and cooling sector in Greece. The novelty of this study is that it unveils the different policy instruments and incentive structures in promoting renewable heating and cooling adoption, and it analyses the social, cultural and technical barriers to the adoption of renewable heating and cooling systems in Greece. To this end, a PESTEL (Political, Economic, Social, Technical, Environmental and Legal) analysis is performed, with a view to demonstrating the factors that affect Greece’s progress against the National Energy and Climate Plans (NECP), the decarbonisation of the heating and cooling sector and finally, the alignment with the long-term energy strategy. Overall, the results of this analysis show that the heating and cooling sector is still greatly dependent on the use of fossil fuels. However, there are more opportunities than barriers for the deployment of the renewable heating and cooling sector in Greece; opportunities arise from the ambitious political goals that are harmonized with those of the EU, targeting climate-neutrality by 2050.