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Green facades applied on a building’s envelope allow achieving the building’s passive thermal control and energy consumption reduction. These are complex systems and many site- and plant-specific parameters influence their energy behavior. The leaf area index (LAI) is a relevant plant characteristic to consider. Solar shading and latent heat loss of plant evapotranspiration are the two main cooling mechanisms. The aim of this study was to assess the cooling effect provided by an evergreen south oriented green facade in summer in a Mediterranean area and to investigate what happens when LAI changes. Experimental data were used to calculate the cooling effect provided by the facade. Simulations with different LAI values were performed to determine the related cooling effect. The canopy solar transmissivity decreased by 54% for every LAI unit increase. LAI significantly influenced the green facade cooling performance. As LAI increased, solar shading and latent heat increased; this was relevant until an upper limit value of 6. An exponential equation to calculate the mean extinction coefficient (km), and a polynomial relationship, with very good agreement, were proposed to calculate shading and latent heat as function of LAI. The findings of this research can effectively contribute to fill still existing gaps on green facades’ energy performance and to the energy simulation of buildings equipped with them.

Saving water is a major challenge to increase environmental sustainability, particularly in semi-arid regions where most table grapes are produced. Water use is driven by atmospheric demand, which combines effects of solar radiation (prominent factor), wind, air temperature and humidity. Covering table grapes with transparent plastics is spread in many regions. Covers lower incoming solar radiation and wind speed, changing air temperature and humidity. This study assessed the effects of two plastic covers on reference evapotranspiration (ET0) in comparison to the open field. For two years, two vineyards (cv. Victoria) trained to overhead trellis systems (tendone) were covered with two transparent polyethylene sheets: an agrotextile fabric (C), and a commercial film (S). The sheet spectrophotometric properties were analyzed and the radiometric coefficients calculated. Micrometeorological data were recorded in the covered vineyards and in a nearby uncovered one. ET0 was calculated for June and July using the simplified Penman–Monteith equation. The coefficient of transmissivity to total photosynthetic radiation, a proxy of net radiation, was 73% for cover C and 83% for cover S. On average, ET0 decreased by 35% under cover C and 31% under cover S. Hence, in addition to providing protection from external agents, covers represent a valid tool for saving water in table grape viticulture; nevertheless, their radiometric properties should be considered and optimized to better achieve this goal.