Search

It is important to manage the environment inside an horticultural greenhouse in order to guarantee suitable growing condition for the crop, safety condition for the workers and energy savings. Microclimate is influenced by climatic parameters, such as solar radiation, air temperature, relative humidity, and wind speed. Evaporative systems are generally used in warm regions for commercial greenhouse cooling, however such systems require large quantity of water that is often a scarce natural resource in Mediterranean areas. Solar absorption systems can be applied for greenhouse cooling in regions with high values of solar irradiation as alternative to evaporative systems by exploiting renewable energy sources. The solar cooling system could provide significant energy-saving opportunities for cooling greenhouses in hot climates allowing the reduction of electricity and water consumption by exploiting the contemporaneity between the cooling requirements and the solar energy availability. The paper presents the technical considerations on the application of a solar absorption cooling system to a greenhouse in the Mediterranean climatic region. The aim of the research was to define the solar collector surface related to the greenhouse cultivated area and the potential of the system in terms of cooling capacity and energy consuption. The simulation study was realized based on the experimental data collected at the experimental centre of the University of Bari, Southern Italy, in order to control the air temperature of a greenhouse covered with plastic film; the greenhouse was characterized by a surface of 300 m2. The cooling system was designed by adopting suitable technologies of energy saving, in order to reduce cooling energy needs. The designed system consists of an absorption chiller having a cooling capacity of 18 kW fed by 50 m2 of evacuated-tube solar collectors coupled to a new distribution system which provides the cooling power only for the air volume surrounding the crop and not for the whole greenhouse.

Nowadays the growth of the cities increased built and paved areas, energy use and heat generation. The phenomenon of urban warming, called urban heat island, influences nega-tively outdoor comfort conditions, pollutants concentration, energy demand for air condition-ing, as well as increases environmental impact due to the demand of energy generation. In-door air temperature depends on a combination of several different parameters related to the climate of the region, the building itself and its use. The main parameters influencing the mi-croclimate are: external air temperature and relative humidity, incident solar radiation, long wave radiation exchange between the structure 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, and electrical equipment. In the Mediterranean region the main problem is to control the solar heat gain that increases building’s temperature during the hot season. Solar heat is trans-ferred to the internal air through the envelope by the heat transfer mechanisms as conduc-tion, convection and radiation. Solar heat can be reduced by increasing the insulation be-tween the exterior and interior of the building, shading the building surface from direct sun exposure, by using an adequate building’s envelope materials or by using green roofs and walls. The use of green roofs and walls can contribute to mitigate the phenomenon of heat island, the emissions of greenhouse gases, and the storm water runoff affecting human thermal comfort, air quality and energy use of the buildings. Aim of this paper is to describe the benefits, the design requirements and plants, and the heat transfer mechanism of green roofs and walls. Green roofs and green vertical systems can be used as passive energy sav-ings systems because they intercept solar radiation by the vegetation, provide thermal insu-lation by the vegetation and substrate, occur evaporative cooling by evapotranspiration from the plants and the substrate, and influence the effect of the wind on the building.

Green infrastructures inside cities represent an effective strategy to face with the increasingly urgent environmental problems. Green systems applied to building envelope are among the most applicable and useful solutions. These provide many significant advantages at different scales. Green façades (GF) are a typology of vertical green systems, applied to the vertical components of the building envelope. GF allow to save energy for air conditioning, by improving the envelope thermal performances. Energy behaviour of GF has been more deeply studied in warm periods, than in cold ones. This paper aims to analyse wintertime energy performances of GF. Evaluations were carried out based on the experimental data collected on two GF, in Bari (Italy), under mediterranean climatic conditions. The experimental set-up included also a bare wall (BW), used as control. The heating effect provided by the greenery was pointed out through statistical and energy analyses. At night-time, the covered walls (CW) were warmer than the bare one up to 3.5°c. The dependence of night-time heating effect on microclimate parameters, as external air temperature, relative humidity and wind speed, was studied. External air temperature was found to be the most influencing factor: as it dropped, the heating effect increased. Overall energy transfer through the CW was lower than through the BW at night-time. The long-wave infrared energy radiative losses were reduced thanks to the green layer, which acted as a thermal barrier. These findings proved that GF improve winter night-time thermal performance by reducing energy losses.

Urban agriculture (UA) initiatives have been increasing in recent years as a nature-based solution for achieving many of the 2030 UN Sustainable Development Goals. However, climate change is expected to have effects on rainfall patterns, which are likely to impact urban food production. The main aim of this paper is to evaluate how issues related to water sources for UA have been addressed in the scientific literature from two different socioeconomic and environmental realities, Brazil and Italy. The method involved a systematic literature review, considering the PRISMA guidelines. The Web of Science database and papers' reference lists were used for retrieving original articles, published in 2000–2020 interval, indexed on scientific databases, and containing data on the typology and quality of water sources used in UA studies. After applying the eligibility criteria, 191 papers were selected – Brazil (108) and Italy (83). The last five years have seen an intensification of studies into issues involving water. Tap water has been identified as an important source of irrigation water for UA, if not the main one. No studies were found that addressed the impact of UA on public water supply systems. The findings point towards more sustainable practices involving the reuse of water and adaptive practices towards water security. We identified that innovative production systems like container farming, aquaponics and indoor agriculture, as well as cultivation of fruit trees, wild edible plants and varieties with low water requirements can represent water-saving options.

The current intensification of the use of plastic materials in agriculture, although has increased significantly the productivity, is also generating growing adverse effects on the environment of the agro-ecosystem. The agriculture is responsible for a massive use of plastic materials, in addition to energy and water inputs, chemical fertilizer and pesticides. Besides the pollution generated during the manufacture, at the end of their lifetime plastic materials used for crop covering, soil mulching, packaging, containers, pots, irrigation and drainage pipes, may became a pollution source when improperly disposed, leaved on the ground or burned. Instead the agricultural plastic waste (APW), if correctly collected, can be used as a new secondary raw material or as an energy source. An adequate APW management can prevent economical losses and environmental damages. The territory of the Barletta, Andria, Trani Province (BAT), in the Apulia Region, South Italy, is an agricultural area characterized by vineyards, olive groves, orchards and vegetables; it represents an area of intense production of plastic wastes and with a widespread problem linked to the application of unacceptable disposal practices. The goal of this study is to define and quantify the different types of plastic waste produced by the agricultural practice in a restricted area of the municipal area of Trani and Barletta, to localize the points where the most remarkable quantities of them are generated, and to provide the local Authorities and the decision makers of a useful tool for implementing an efficient and effective waste management. A dedicated geo-referenced database was designed using land use maps in a GIS environment and applying a methodology that can be functional for any kind of agricultural plastic waste. The resulting database gives updated and complete information on the plastic waste generation, over the land, related to the cultivation kind.

Greenhouse microclimate depends on climatic parameters, such as solar radiation, air temperature, relative humidity and wind speed. The management of the greenhouse environment aims to ensure suitable growing condition for the crop, energy savings, and also safety condition for the workers. Solar absorption systems, exploiting renewable energy sources, can be applied for greenhouse cooling in regions with high values of solar irradiation in which evaporative systems are generally used; nevertheless evaporative systems require large quantity of water that is often a scarce natural resource in Mediterranean areas. The paper presents the technical considerations on the application of thermal solar collectors and an absorption system for cooling a greenhouse in the Mediterranean area. The simulation study was realized based on the data collected at the experimental centre of the University of Bari, Southern Italy, aiming to control the air temperature of a greenhouse having a surface of 300 m2. The study aims to delineate the solar collector surface related to the greenhouse cultivated area and the potential of the system in terms of cooling capacity and energy consumption. The designed system consists of 60 m2 of evacuated-tube solar collectors, a single-effect absorption chiller having a cooling capacity of 18 kW and a pilot distribution system, which provides the cooling power for the air volume surrounding the crop. The simulation showed that the delivered yearly cooling capacity for the greenhouse was 113 GJ, the required solar energy 157 GJ and the available solar energy 234 GJ.

Plastic materials are generally used for several agricultural applications and, at the end of their lifetime, they produce high volumes of waste to be disposed. A non suitable disposal system for agricultural plastic waste could induce economical damages, negative effects on the natural landscape and on the agroecosystem with loss of material or energy. Optimizing the processes of collection, transport and final disposal, the agricultural plastic wastes become "secondary raw materials", technically efficient and economically feasible, that can be reused for also other different applications. The problem of the management of the plastic waste flux coming from agricultural activities is still far to be solved in some Italian areas. In the present paper the management of agricultural plastic wastes was evaluated by means of the SWOT (Strengths Weaknesses Opportunities Threats) analysis and the application of a Geographical Information System (G.I.S). The methodology was applied to the municipality of Trani, in the Barletta, Andria, Trani Province (BAT), in Apulia Region, South Italy. The SWOT analysis was used to evaluate the whole process concerning the waste management, the GIS methodology was used to quantify plastic wastes generation on the land.

The phenomenon of urban warming, known as urban heat island, negatively influences outdoor comfort conditions and pollutants concentration, as well as increases the environmental impact due to the energy demand for air conditioning. In Mediterranean climate regions the main problem is to control the solar heat gain, that increases building’s temperature during the hot season, in order to protect the conditions of well-being of those who live or work in the buildings. Solar heat can be mainly reduced by increasing the insulation between the exterior and interior of the building, as well as shading the building surface from direct sun exposure. A sustainable technology for improving the energy efficiency of buildings is the use of green roofs and green walls in order both to reduce the energy consumption for conditioning in summer by physically shading the building structures and by promoting evapotranspiration, and to increase the thermal insulation in winter. Aim of this paper is to describe the green roofs and walls design requirements and to develop an energetic model capable of simulating the energy exchanges that take place in the presence of roofs / green walls. The energy model of the microclimate inside a building covered with plant species in Mediterranean climate depends on several different parameters that influence the indoor building microclimate such as external air temperature and relative humidity, incident solar radiation, long wave radiation exchange between the structure 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. The model takes into account also the effect of different plant species. Solar heat is transferred to the internal air through the envelope by the heat transfer mechanisms as conduction, convection and radiation. The physical properties of the surface, such as the solar reflectance, infrared emittance and the convection coefficient, influence the surface temperature. The use of green roofs and walls can contribute to mitigate the phenomenon of heat island, the emissions of greenhouse gases and the storm water runoff affecting human thermal comfort, air quality and energy consumption in buildings.

Evaporative systems are generally used in warm regions for commercial greenhouse cooling, such systems require large quantity of water that is often a scarce natural resource in Mediterranean areas. Solar absorption cooling systems can be applied for greenhouse climate control in regions with high values of solar irradiation as alternative to evaporative systems by exploiting renewable energy sources. The paper presents the preliminary results of a research on the application of a solar absorption cooling system to a Mediterranean greenhouse. The aim of the research was to assess the potential of the system in terms of energy absorption related to the solar collector surface and to the greenhouse covered area. The simulation study was realized based on the experimental data collected at the experimental centre of the University of Bari, Southern Italy, in order to control the temperature of a plastic film covered greenhouse, having a surface of 300 m2. The cooling system was designed by adopting suitable technologies of energy saving, in order to reduce cooling energy needs. The designed system consists of an absorption chiller having a cooling capacity of 35 kW and of 80 m2 of evacuated-tube solar collectors.

The management of the greenhouse environment depends on the manipulation of the climat-ic parameters, such as solar radiation, air temperature, relative humidity and carbon dioxide concentration, in order to guarantee suitable growing condition for the crop, safety condition for the workers and energy savings. Evaporative systems are generally used in warm regions for commercial greenhouse cooling, however such systems require large quantity of water that is often a scarce natural resource in Mediterranean areas. Solar absorption cooling sys-tems can be applied for greenhouse climate control in regions with high values of solar irra-diation as alternative to evaporative systems by exploiting renewable energy sources. The solar cooling system could provide significant energy-saving opportunities for cooling green-houses in hot climates allowing the reduction of electricity and water consumption by exploit-ing the contemporaneity between the cooling requirements and the solar energy availability. The paper presents the technical considerations on the application of a solar absorption cool-ing system to a Mediterranean greenhouse. The aim of the research was to define the poten-tial of the system in terms of energy absorption and the solar collector surface related to the greenhouse cultivated area. The simulation study was realized based on the experimental data collected at the experimental centre of the University of Bari, Southern Italy, in order to control the air temperature of a greenhouse covered with plastic film; the greenhouse was characterized by a surface of 300 m2. The cooling system was designed by adopting suitable technologies of energy saving, in order to reduce cooling energy needs. The designed sys-tem consists of an absorption chiller having a cooling capacity of 18 kW fed by 60 m2 of evacuated-tube solar collectors coupled to a new distribution system which provides the cooling power only for the air volume surrounding the crop and not for the whole greenhouse.

The phenomenon of urban warming, known as urban heat island, negatively influences outdoor comfort conditions and pollutants concentration and as well increases the environmental impact due to the energy demand for air conditioning. Urban warming can be attenuated by reducing the solar heat gain that increases building’s temperature during the hot season. Solar heat can be mainly reduced by increasing the insulation between the exterior and interior of the building, as well as by shading the building surface from direct sun exposure. A sustainable technology for improving the energy efficiency of buildings is the use of green roofs and green walls that: allow the physical shading of the building and promote evapotranspiration in summer; increase the thermal insulation in winter. An experimental test was carried out at the University of Bari (Italy, 41 ° 05 'N, 16 ° 53 'E). Three prototypes of building vertical wall, made with perforated bricks, were designed: two vertical walls were covered with plants (one with Pandorea jasminoides variegated, the second with Rhyncospermum jasminoides) while the third wall was kept uncovered and was 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, external air temperature and wind speed. During summer 2014 the diurnal temperatures of the control surface exposed to the solar radiation were higher by about 4 °C compared to the temperatures recorded on both the vertical walls covered with Rhyncospermum jasminoides and Pandorea jasminoides variegated. The thermal wave propagated with a phase shift of about 2 hours and half.