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A sustainable and environmentally alternative to commonly used air conditioning systems can be the solar cooling system due to the use of renewable and clean energy. Solar absorption systems can be used for greenhouse cooling in areas with high outdoor temperatures and solar radiation levels. These systems take advantage of the simultaneity between the solar energy availability and the greenhouse cooling demand allowing the reduction of conventional electricity and water consumption. This paper presents the results of the application of a solar cooling plant for the climate control of a greenhouse at the University of Bari, Italy. The experimental plant consists of a Mediterranean greenhouse, having a surface of 300 m2, and of a single effect LiBr-H2O absorption chiller fed by evacuated-tube solar collectors. Two different localized systems were chosen for the distribution of cold inside the greenhouse: the first system presents pipes placed centrally on the cultivation vessels; the second consists of pipes in contact with aluminium plates and of a transparent EVA film, used to border an area close to plants. The distribution system of cold with pipes, plate and EVA film provided a slightly higher cooling capacity due to the presence of the plates which increases the ability to dissipate energy.

Greenhouse microclimate control is important to reach high production yield and low environmental impacts. Ventilation, shading and evaporative cooling are methods for controlling air temperature and relative humidity inside the greenhouse. Ventilation and shading can be not sufficient to remove the excess heat, while evaporative cooling is based on the exploitation of huge amounts of water. In order to enhance the sustainability of the greenhouse industry, renewable energy sources can be exploited. Solar absorption systems can be used for greenhouse cooling in areas with high outdoor temperatures and solar radiation levels. These systems take advantage of the simultaneity between the solar energy availability and the greenhouse cooling demand allowing the reduction of conventional electricity and water consumption. They can be used in remote areas where conventional cooling is difficult and where there is abundant solar energy. This paper presents the results of the application of a solar cooling plant for climate control of a greenhouse. The system is sited at the University of Bari, Italy. The experimental plant consists of a Mediterranean greenhouse, having a surface of 300 m2 and by a single effect LiBr-H2O absorption chiller fed by evacuated-tube solar collectors. The application of two different localized distribution of cold inside the greenhouse was studied in order to evaluate the reduction of air temperature close to the cultivation area. A reduction of the greenhouse air temperature up 5.0°C was obtained.

Urban Green Infrastructures (UGIs) improve the supply of urban ecosystem services. UGIs can provide benefits such as better urban climate conditions and lower temperature of urban air. They can also limit the development of extreme temperatures on buildings surface, in particular in Mediterranean climate areas. Green facades permit the physical shading of the building envelope, produce a cooling effect by means of evapotranspiration in summer, and improve the thermal insulation in winter. A reduction of the thermal flows between exterior and interior and more sustainable buildings can be obtained. A three years experimental test was carried out at the University of Bari (Italy) for assessing the thermal performance of two green facades characterized by two different climbing plants (Pandorea jasminoides variegated and Rhyncospermum jasminoides). The selected plants well adapt to the local climate, growing quickly and vigorously. The environmental conditions and several climatic parameters on the walls were monitored during the field test. The temperature on the external surface during July 2015 was used for fitting a regression model. The model was validated on July 2016. It can be applied for predicting the two green facades performance in a Mediterranean climate only by using an input dataset on climate conditions.

A sustainable technology for improving the energy efficiency of buildings is the use of urban greening in order to reduce the energy consumption for air conditioning in summer and to increase the thermal insulation in winter. A worldwide growing interest in urban green is encouraging the application of the greening technology for more sustainable buildings. Building indoor air temperature depends on several different parameters related to the climate of the region, the building itself and its use. The main parameters influencing the microclimate are: external air temperature and relative humidity, incident solar radiation, long wave radiation exchange between the building surfaces and its surroundings, wind velocity and direction, air exchanges, physical and thermal properties of the building's envelope materials, design variables such as building dimensions and orientation, presence of artificial light, electrical equipment. Green façades can allow the physical shading of the building and promote evapotranspiration in summer and increase the thermal insulation in winter. External wall surface temperature is a parameter useful to assess the effectiveness of green façades. An experimental test was carried out at the University of Bari (Italy) for three years. Three vertical walls, made with perforated bricks, were tested: two were covered with evergreen plants (Pandorea jasminoides variegated and Rhyncospermum jasminoides) while the third wall was kept uncovered and used as control. Several climatic parameters concerning the walls and the ambient conditions were collected during the experimental test. The experimental data were used for developing a multiple regression equation regarding the dependence of the difference of external surface temperature between the green façades and the control wall and the weather conditions. The model shows a good predicting ability.

Plastic materials used in agriculture mostly derive from synthetic petro-chemical polymers. They require at the end of their lifetime a suitable waste management system for the collection and treatment. A research was carried out in order to define a GIS methodology for mapping the agricultural plastic waste on the land. The use in agriculture of plastics in Barletta-Andria-Trani Province – Apulia Region – was investigated by applying orthophotos analysis and remote sensing survey. Besides purposed Plastic Waste Indexes were created to release land use to waste generation. The data were organized in a specific geo-database. The analysis showed that the agricultural plastic waste yearly produced from covering films was 627 kg ha−1, from the anti-hail nets was 159 kg ha−1, from nets for crop protection was 192 kg ha−1, from shading nets was 131 kg ha−1, from irrigation pipes was 104 kg ha−1. Through GIS, the areas with high density of plastic wastes were pointed out and the suitable location of collection centres was defined. The produced maps and the GIS database can be always updatable tools, useful for monitoring and optimizing the collection of agricultural plastic waste from the farms and their transport to the recycling companies.

Green facades can represent a sustainable solution for construction of new buildings and for retrofitting of existing buildings, in order to reduce the energy demands of the cooling systems, to mitigate the urban heat island and to improve the thermal energy performance of buildings. Green facades can allow the physical shading of the building and promote evapotranspiration in summer, and increase the thermal insulation in winter. An experimental test was carried out at the University of Bari (Italy) for two years. Three vertical walls, made with perforated bricks, were tested: two were covered with evergreen plants (Pandorea jasminoides variegated and Rhyncospermum jasminoides) while the third wall was kept uncovered and used as control. Several climatic parameters concerning the walls and the ambient conditions were collected during the experimental test. The daylight temperatures observed on the shielded walls during warm days were lower than the respective temperatures of the uncovered wall up to 9.0 °C. The nighttime temperatures during the cold days for the vegetated walls were higher than the respective temperatures of the control wall up to 3.5 °C. The thermal effects of the facades at daytime was driven by solar radiation, wind velocity and air relative humidity. The highest cooling effect of such parameters occurred with a wind speed of 3–4 ms−1, an air relative humidity within the range 30–60% and a solar radiation higher than 800 Wm−2. The long-term experimental test demonstrated that both Pandorea jasminoides variegated and Rhyncospermum jasminoides are suitable for green facades in the Mediterranean climatic area. The results shown in the present research allow to fill the gap in literature concerning the lack of data for all the seasons of the year, in order to obtain a complete picture of the building thermal performance in the Mediterranean climate region.

Green vertical systems have advantages in terms of building energy performance, but their environmental impact should be assessed in comparison to un-vegetated constructive systems. The aim of this paper was to evaluate the environmental loads of a green façade, which was compared to other building exterior wall systems. A Life Cycle Analysis approach was used to compare the green façade with constructive solutions commonly applied for enhancing the thermal insulation properties of the building exterior walls. The green façade and the other constructive solutions were characterised by an equivalent thermal behaviour. A green façade system prototype, realised with vegetation climbing on a steel frame, was used for the study. The comparison was carried out with exterior walls using insulation materials as expanded polystyrene, expanded cork and wood fibre. A double wall with an un-ventilated air gap was used as well. On average, the best environmental performance was recorded for the wall using cork as insulating material and for the double wall. The results highlighted the environmental criticalities of the green façade as the system having an environmental load among the most burdensome. Different scenarios of green façade with the use of alternative constructive solutions were hypothesized and compared by the life cycle analysis and life cycle impact assessment. The study showed that the adoption of a wooden frame in place of the steel one, as plant supporting structure, reduces the carbon footprint of the green façade by 58%. The environmental comparison was carried out also considering non-vegetated constructive solutions having an equivalent sun shading effect on the wall. The analysis showed that the green façade has the best environmental performance when compared with sun shading systems in aluminium or PVC.

Energy performance of a double-skin green facade in Mediterranean climate was investigated. Experimental data were collected at a green facade prototype realized at the University of Bari. The green facade thermal behaviour was assessed under different summertime weather scenarios. To point out the plants influence, a comparison was carried out between microclimatic conditions and energy transfer at the covered wall, behind the vegetation, and at an un-vegetated wall. Experimental data concerning the walls surface, the air gap in the green facade and the external air were used to perform statistical analyses and to evaluate the heat fluxes. At daytime, the green facade provided a reduction of the wall surface temperature up to 9.9 °C, while air relative humidity behind the vegetation rose up to 18.7%. Surface and air warming were found at night-time. A time-shift was detected between the maximum surface temperature of the covered and of the bare wall. The analysis of the energy flux through the two walls highlighted a sensible reduction in the covered wall, equal to 62% during daytime. Solar and LWIR radiative and convective fluxes were generally lower in the covered wall. Latent heat due to evapotranspiration was evaluated, as well. Net radiation was found to be the most influencing parameter for latent heat transfer. A simplified relationship was proposed to quantify latent heat due to evapotranspiration. The formula based on the net radiation, as input parameter, was found to be the most suitable. The findings of this research contribute to the knowledge of the effects provided by green facades in terms of cooling and heating, influence on the proximity microclimatic conditions and overall energy transfer.

The use of plastic materials in agriculture involves several benefits but it results in huge quantities of agricultural plastic waste to be disposed of. Input and output data on the use of plastics in agriculture are often difficult to obtain and poor waste management schemes have been developed. The present research aims to estimate and map agricultural plastic waste by using satellite images. Waste was evaluated by means of the indexes relating waste production to crop type and plastic application as defined by the land use map realized by classifying the Landsat 8 image. The image classification was carried out using Support Vector Machines (SVMs), and the accuracy assessment showed that the overall accuracy was 94.54% and the kappa coefficient equal to 0.934. Data on the plastic waste obtained by the satellite land use map were compared with the data obtained by using the institutional land use map; a difference of 1.74% was identified on the overall quantity of waste.

Increasing urban green infrastructure (UGI) in a city contributes to improve urban air quality and urban climate in summer, reducing buildings surface temperature, especially in southern Europe. UGI includes green walls and their correct application requires the knowledge of the energy performance of the applied green system. The effects of the green walls application on the building depend on the local climate, water availability, building shape. The presence of green walls affects the building microclimate all day, by reducing heat waves during the warm periods and heat losses from the building in cold periods. The heat and mass transfer between the external environment, the green wall and the building surface determine the building microclimate. Solar radiation, long wave infrared radiation, convective heat transfer and evapotranspiration are the main mechanism of heat transfer in a green wall. The paper describes the main parameters concerning heat flow in green walls that can be used in simulation models for predicting temperatures in buildings using the external weather conditions as model inputs. The green wall system was described by a schematic representation, the following layers were defined: the green wall, the gap air, the external surface of the building wall, the internal surface of the building wall, the air inside the building. The energy balance was defined for each layer and all the terms involved in the energy exchange between the layers were defined.

Green technology can represent a sustainable solution for construction of new buildings and for retrofitting of existing buildings, in order to reduce the energy demands of the buildings’ cooling systems, to mitigate the urban heat island and to improve the thermal energy performance of buildings. Green walls can allow the physical shading of the building, promote evapotranspiration in summer and increase thermal insulation in winter. An experimental test was carried out at the University of Bari (Italy) for 2 years. Three vertical walls, made with perforated bricks, were tested: two were covered with evergreen plants (Pandorea jasminoides and Rhyncospermum jasminoides), while the third wall was kept uncovered and used as a control. Several climatic parameters concerning the walls and the ambient conditions were collected during the experimental test. Daylight temperatures observed on the shielded walls during warm days were lower than the respective temperatures of the uncovered wall by up to 9.0°C. Night-time temperatures during cold days for the vegetated walls were higher than the respective temperatures of the control wall by up to 6.0°C. The absence in the literature of data concerning different seasons of the year is overcome in order to obtain a complete picture of building thermal performance in the Mediterranean climate region. © 2018 International Society for Horticultural Science. All Rights Reserved.

Building greenery systems can represent a sustainable solution for new buildings design and for existing buildings retrofitting, in order to improve the thermal energy performance of buildings, to decrease building energy loads and to contrast the Urban Heat Island. Green façades can influence thermal properties of a building by means of different important mechanisms: the shading, the cooling, the insulating and the wind barrier effect. Moreover, green façades accomplish heating effect in the cold season and at nighttime. An experimental test was developed at small scale at the University of Bari (Italy) from 2014 to 2016 for testing two different green façades. The plant species chosen were Pandorea jasminoides variegated and Rhyncospermum jasminoides, two evergreen climbing plants. A third uncovered wall was used as control. The thermal behaviour of the plants was analysed during the 2016 summer season, by keeping in consideration the external surface temperature of the building and the temperature of the airgap behind the green vertical systems. The daylight temperatures observed on the plant-covered walls during representative days were lower than the respective temperatures of the uncovered wall up to 7.0°C. During nighttime, the temperatures behind the plants were higher than the respective temperatures of the control wall up to 2.2°C. The results shown in the present research allow delineating the behaviour of the two plant species during summer in the Mediterranean climate region.

Green technology can represent a sustainable solution for construction of new buildings and for retrofitting of existing buildings, in order to reduce the energy demands of the cooling systems of buildings, to mitigate the urban heat island and to improve the thermal energy performance of buildings. Green walls can allow the physical shading of the building and promote evapotranspiration in summer and increase the thermal insulation in winter. Three vertical walls, made with perforated bricks, were tested at the University of Bari (Italy): two were covered with evergreen plants (Pandorea jasminoides variegated and Rhyncospermum jasminoides) while the third wall was kept uncovered and used as control. Several climatic parameters concerning the walls and the ambient conditions were collected during the experimental test. The daylight temperatures observed on the shielded walls during warm days were lower than the respective temperatures of the uncovered wall up to 8.4°C. The night-time temperatures during the cold days for the vegetated walls were higher than the respective temperatures of the control wall up to 3.6°C. © ISHS.

Building indoor air temperature depends on several different parameters related to the climate of the region, the building itself and its use. The main parameters influencing the microclimate are: external air temperature and relative humidity, incident solar radiation, long wave radiation exchange between the building surfaces and its surroundings, incidence and speed of the wind, air exchanges, physical and thermal properties of the building's envelope materials, design variables such as building dimensions and orientation, presence of artificial light, electrical equipment. A sustainable technology for improving the energy efficiency of buildings and to mitigate urban heat island is the use of green roofs and walls. The green technology can allow the physical shading of the building and promote evapotranspiration in summer and increase the thermal insulation in winter. An experimental test was carried out at the University of Bari (Italy). Three vertical walls, made with perforated bricks, were tested: two were covered with plants (one with Pandorea jasminoides variegated, the second with Rhyncospermum jasminoides) while the third wall was kept uncovered and used as control. A system composed by a data logger and sensors was used to measure and record the following parameters: temperature of the wall surface under solar radiation and of the surface on the other side of the wall, solar radiation falling on the wall, and external air temperature. The use of the green walls during cold months allowed increasing the thermal insulation performance of the walls by keeping the external surface temperature in nighttime hours up to about 2.8°C over the surface temperature of the wall not covered with plants. © 2017 ISHS.

Monitoring and controlling environmental parameters inside a greenhouse are required to reach high yields and low environmental impacts. Ventilation, shading, evaporative cooling and refrigeration are methods of controlling air temperature and relative humidity in Mediterranean greenhouses. Nevertheless ventilation and shading are often not sufficient to remove the excess heat, refrigeration is generally expensive and evaporative cooling is based on the exploitation of high quality water, a resource to be preserved in the Mediterranean areas. In order to enhance the sustainability levels of the greenhouse sector, renewable energy sources can be exploited with the application of solar absorption systems for greenhouse cooling in areas with high outdoor temperatures. These systems take advantage of the simultaneity between the solar energy availability and the greenhouse cooling demand allowing the reduction of conventional electricity. This paper presents the simulation and optimization of a solar cooling system designed for a Mediterranean greenhouse, having a surface of 300 m2, using 68 m2 of evacuated tube solar collectors, a LiBr absorption unit with a cooling capacity of 17.6 kW and a pilot distribution system providing the cooling power for the volume surrounding the crop. The simulation study, predicting the performance of the unit, was based on the experimental data collected at the experimental centre of the University of Bari, Southern Italy. The results of the simulation indicated that the system is seasonally in phase with the climatic data; the delivered yearly cooling capacity for the greenhouse was 113 GJ, the required solar energy 157 GJ and the available solar energy on the 68 m2 capturing surface, with a slope of 30°, was 265 GJ. The simulation can be used as a forecasting tool of the effects of the changes on the parameters of the system before applying them on the greenhouse system. © 2017 ISHS.

The thermal potential of vertical greenery systems in buildings can be fully explored through modelling. Models support designers in choosing between different technical solutions. This study analyses the cooling effect of two plants suitable for the Mediterranean area. A regression model simulating the difference of the wall external surface temperature between the wall covered with vegetation and an uncovered wall was developed. In order to overcome the gaps in literature, the model was fitted and validated on long period experimental data. It was based only on the use of climatic conditions as input variables, without making assumptions about the plants. Climatic data were grouped in solar radiation slots; the most significant predictors were selected for each slot. The adoption of this method allowed to obtain, during validation, coefficients of determination (R2) higher than 0.95 and low values of the root mean square error (0.4–0.6 °C). It was found that the vegetated walls recorded surface temperatures lower than the uncovered wall up to 7.7 °C in summertime. The results showed that the model developed with a statistical approach can efficiently be used for simulating the thermal effects of a green facade in a similar Mediterranean climate.