Application of solar assisted heat pump technology to the Palacus Sport Palace: renewable sources integration for highly efficient and low energy consumption systems

The present work is concerned with the plant of the sport palace “Carmine Romanzi”, known also as “Palacus”, of University of Genoa (Italy). The facility consists of a heat pump coupled, on the cold side, with the thermal part of a solar hybrid field. The hot side of the heat pump has been designed to satisfy the space heating and domestic hot water needs of the structure. The photovoltaic production of the solar hybrid field grants the electricity need of the heat pump and any other electric auxiliary within the plant. Two traditional gas burners integrate the space heating or the domestic hot water production in case of severe boundary conditions (e.g. users’ needs and environmental conditions). Finally there is also a data acquisition and monitoring system in the installation to allow an almost continuous monitoring of the plant. The research topic is about the plant monitoring with the aim of optimal strategies definition in order to maximize the exploitation of the renewable part of the plant. This objective has been achieved thanks to both the data acquired by means of the monitoring system and numerical dynamic simulations carried out with numerical codes (Matlab and TRNSYS). In my opinion, the technology of the solar assisted heat pump (SAHP) still hasn’t been fully appreciated for technical and complexity reasons. Besides the academic and practical issues, the underlying goal of this work is to give a little contribution to reach more competitive and attractive asset. The expectation is to transmit the “hands-on” experience gained along the past three years of my PhD and make it available for others who might treasure it. This study shows a very high level of multidisciplinary since the pilot plant provides the thermal needs of a real structure with real users. It no-longer belongs to a didactic workbench where the boundary conditions (e.g. external temperature, irradiance, thermal loads) were simulated “ad hoc”. The plant faces every day the double challenge of the competition with the traditional heating installation trying to provide the users’ needs (space heating, domestic hot water) with the maximum, optimal exploitation of the renewable sources. The structure of the following chapters is conceived as a report journal where each relevant issue has been illustrated in a specific section. The common goal is the achievement of a low consumption and energy efficient system that can be managed from two main approaches. Firstly, the topic of acceptance namely how the end users’ agreeement influences the usage of the plant and therefore its performance (Chapter 2). Secondly, the field of numerical transient simulations for complex plants has been enquired by means of applications in Trnsys environment (Chapter 3). The two paths have led both to significative material improvements of the plant which have been realised during the past three years and they have provided the chance to deepen specific academic topics (e.g. stratification, validation of different numerical models to simulate specific subsystems of the plant, introduction of new methods to asses a level of acceptance of the facility). In the end, the knowledge acquired by means of the almost continuous monitoring of the plant has been applied to support both the decision making and the design teams in the choice of the new configuration to give to the plant according to the revamping intervention which is taking place. In other words, the key concepts introduced in the last part of this work have been implemented in the revamping design to reach a better plant performance and they are the result of the experience, data acquisition and management, numerical analyses and simulations about the pilot plant performed during the past three years (Chapter 4).