Alberto Barbaresi

Retrofit interventions in non-conditioned rooms: calibration of an assessment method on a farm winery

In the Mediterranean area, most wine farms make use of unconditioned above-ground buildings for wine conservation and ageing. Those buildings are usually constructed without a specific temperature control design, therefore indoor temperature distributions and trends can be suboptimal for wine storage. At the same time, various elements (commonly available in farms such as straw bales and climbing plants) could be used to create cheap constructive solutions capable of improving buildings thermal behaviour. This study aims to test the effectiveness of different retrofit interventions for thermal behaviour improvement in unconditioned above-ground farm buildings, referring to wine-ageing requirements. The alternative design solutions are evaluated through energy simulations, calibrated and validated on an Italian case study. The results show the importance of roof insulation, and the improved performance of the combination of more retrofit strategies. The proposed approach can be extended to other passive strategies and proves useful to provide information to optimize, or even avoid, conditioning systems.

Low-cost micro-thermal response test system for characterizing very shallow geothermal energy

Shallow Geothermal Systems (SGS) are widely used to provide low-cost heating and cooling of residential and commercial buildings. SGS can be an economically-viable solution even for commercial buildings, where controlled temperature is fundamental for the production processes. To assess the thermal resistance of the soil and the performance of a SGS, Thermal Response Tests (TRT) must be performed. TRT machines are today designed mainly for short term monitoring, for relatively deep SGS (up to 200 m) and for being used by expert operators. Lightweight, low-cost machines for both fast and long term, reliable and unattended TRT for very Shallow Geothermal Systems (vSGS) are not available today. This paper describes the design of a micro-TRT machine (mTRT) for vSGS, which is gaining interest in the civil engineering, environmental, energy and food chain sectors. The paper describes the features of the wireless monitoring system, the design choices to achieve the required accuracy and the software developed for adding remote control capability. Experimental validation in a real test field demonstrates the quality of measurements collected for analysing the TRT data.

Long-Range Radio for Underground Sensors in Geothermal Energy Systems

The paper presents the design of a temperature monitoring system in a very harsh environment, such as Shallow Geothermal Systems (SGS), where the information of underground temperature is necessary to assess the thermal potential of the soil, for maximizing the efficiency of the SGS. The challenge is to get information at different depths (sometimes up to −100 m), to transmit data wirelessly in rural areas where conventional wireless connections (e.g. WiFi, GSM) are not guaranteed and energy availability poses severe limits. Our design exploits a recent new modulation protocol developed for long-range transmission, at the minimum energy cost, and a two-tier hardware architecture for measuring underground temperature. Aggressive duty cycling permits to achieve lifetime of several years. Experimental results demonstrate the utility of such a system during the design and the operational activity of a SGS.