• Energy Research

In arid climates, the optical properties of plastic-covered greenhouses deteriorate very quickly. To examine the effect of greenhouse shape and orientation on the degradation rate of cover optical properties, four greenhouse prototypes were constructed in two shapes (duo-pitched roof and tunnel), covered with a 200 µm thick low-density polyethylene film. Two types were oriented in the North–South direction, the other two in the East–West direction, and all were exposed for one year to an arid climate. Samples were taken from the different surfaces of each cover for testing. The total transmittance (Ts) and reflectance (Rs) of the samples were measured and averaged to obtain the whole cover properties (T and R). Measurements were carried out periodically every 30 days for the four prototypes. The degradation behavior of the optical properties of each cover surface (Ts, Rs) and the whole cover (T, R) was investigated for the four film covers during the exposure time. Results show that the degradation rate of Ts depends on the surface location and the cover orientation. Among the different surfaces of the four prototype covers, the maximum difference in the Ts value between the E and N surfaces for the tunnel cover oriented in the N–S direction was 15.5%. Although the variation of the Ts value among the different cover surfaces was found, the time dependences of the whole cover transmittance (T) for the four covers tested were almost similar. Accordingly, the shape and orientation of the small size greenhouses did not significantly affect the degradation rate of the cover optical properties. In the four covers tested, the reduction in the global solar radiation transmittance (T) was 27–31% after one-year exposure compared to the new film. Nonlinear correlation was developed to predict the degradation rate of the cover transmittance as a function of the accumulated solar irradiance.

In arid climates, the optical properties of plastic-covered greenhouses deteriorate very quickly. To examine the effect of greenhouse shape and orientation on the degradation rate of cover optical properties, four greenhouse prototypes were constructed in two shapes (duo-pitched roof and tunnel), covered with a 200 µm thick low-density polyethylene film. Two types were oriented in the North–South direction, the other two in the East–West direction, and all were exposed for one year to an arid climate. Samples were taken from the different surfaces of each cover for testing. The total transmittance (Ts) and reflectance (Rs) of the samples were measured and averaged to obtain the whole cover properties (T and R). Measurements were carried out periodically every 30 days for the four prototypes. The degradation behavior of the optical properties of each cover surface (Ts, Rs) and the whole cover (T, R) was investigated for the four film covers during the exposure time. Results show that the degradation rate of Ts depends on the surface location and the cover orientation. Among the different surfaces of the four prototype covers, the maximum difference in the Ts value between the E and N surfaces for the tunnel cover oriented in the N–S direction was 15.5%. Although the variation of the Ts value among the different cover surfaces was found, the time dependences of the whole cover transmittance (T) for the four covers tested were almost similar. Accordingly, the shape and orientation of the small size greenhouses did not significantly affect the degradation rate of the cover optical properties. In the four covers tested, the reduction in the global solar radiation transmittance (T) was 27–31% after one-year exposure compared to the new film. Nonlinear correlation was developed to predict the degradation rate of the cover transmittance as a function of the accumulated solar irradiance.

Due to several growing environmental constraints, renewable energy sources currently play an increasingly crucial role that, owing to their high temporal and spatial variability, needs a careful planning approach. It is important therefore to develop a framework that examines the distribution of different energy sources in a spatio-temporal context. From an energy point of view, a regional territory, such as an internal southern Italian region (the Basilicata Region), can be considered as a paradigmatic case study, because it is characterized by significant sources of renewable energy (e.g., biomass, wind, solar, hydro) connected to its morphological and environmental structure, as well as to its agricultural and food productions. The present paper in based on an analysis of the spatial supply and relationships between renewable energy potentials and rural land, through the use of a Geographic Information System that has been implemented with the aim to analyze the energy system, as well as to optimize the valorization of biomass resources that may be still unutilized within the bioenergy production chain. This study has been carried out even to bridge the gap between energy systems modeling and landscape planning. Within this context, an “Energyscape” may be considered as the effect resulting on the rural landscape from a combination of the supply, demand and infrastructure for energy. This framework could be therefore a starting point for an interdisciplinary analysis able to figure out optimal solutions in decision-making processes, which duly respect the protection and restoring of endangered ecosystems, supporting the decision about an optimal spatial localization of energy plants as well.

Due to several growing environmental constraints, renewable energy sources currently play an increasingly crucial role that, owing to their high temporal and spatial variability, needs a careful planning approach. It is important therefore to develop a framework that examines the distribution of different energy sources in a spatio-temporal context. From an energy point of view, a regional territory, such as an internal southern Italian region (the Basilicata Region), can be considered as a paradigmatic case study, because it is characterized by significant sources of renewable energy (e.g., biomass, wind, solar, hydro) connected to its morphological and environmental structure, as well as to its agricultural and food productions. The present paper in based on an analysis of the spatial supply and relationships between renewable energy potentials and rural land, through the use of a Geographic Information System that has been implemented with the aim to analyze the energy system, as well as to optimize the valorization of biomass resources that may be still unutilized within the bioenergy production chain. This study has been carried out even to bridge the gap between energy systems modeling and landscape planning. Within this context, an “Energyscape” may be considered as the effect resulting on the rural landscape from a combination of the supply, demand and infrastructure for energy. This framework could be therefore a starting point for an interdisciplinary analysis able to figure out optimal solutions in decision-making processes, which duly respect the protection and restoring of endangered ecosystems, supporting the decision about an optimal spatial localization of energy plants as well.

The transmitted radiation into the conventional net-houses is very low in the early morning and late afternoon that may not fulfill the crop growth requirements. To solve this problem, two types of net-house models (polygon and curved-arch net-houses) were newly designed, each having seven surfaces made up of different net types. The spectral radiative properties of 32 nets were examined and three nets were selected to cover the surfaces of each model. The two designs showed high transmittance in the morning and afternoon, and low at around noon (U shape). The polygon style was scaled-up and an experiential net-house was constructed with a floor area of 28 m2. An evaporatively-cooled greenhouse with a floor area of 28 m2 was used for comparison; each floor was planted with 500 potted Chrysanthemum plant. The results showed that the PAR and microclimate in the net-house and cooled greenhouse were similar. The net-house reduced water consumption by 13 kg m−2 day−1 in summer and by 0.94 kg m−2 day−1 in winter; and reduced electric energy consumption by 0.26 kw-h m−2 day−1 in summer and by 0.18 kw-h m−2 day−1 in winter compared to the greenhouse.

The transmitted radiation into the conventional net-houses is very low in the early morning and late afternoon that may not fulfill the crop growth requirements. To solve this problem, two types of net-house models (polygon and curved-arch net-houses) were newly designed, each having seven surfaces made up of different net types. The spectral radiative properties of 32 nets were examined and three nets were selected to cover the surfaces of each model. The two designs showed high transmittance in the morning and afternoon, and low at around noon (U shape). The polygon style was scaled-up and an experiential net-house was constructed with a floor area of 28 m2. An evaporatively-cooled greenhouse with a floor area of 28 m2 was used for comparison; each floor was planted with 500 potted Chrysanthemum plant. The results showed that the PAR and microclimate in the net-house and cooled greenhouse were similar. The net-house reduced water consumption by 13 kg m−2 day−1 in summer and by 0.94 kg m−2 day−1 in winter; and reduced electric energy consumption by 0.26 kw-h m−2 day−1 in summer and by 0.18 kw-h m−2 day−1 in winter compared to the greenhouse.

The agricultural sector has benefitted over the last century from several factors that have led to an exponential increase in its productive efficiency. The increasing use of new materials, such as plastics, has been one of the most important factors, as they have allowed for increased production in a simpler and more economical way. Various polymer types are used in different phases of the agricultural production cycle, but when their use is incorrectly managed, it can lead to different environmental impacts. In this study, an applied and simplified methodology to manage agricultural plastics monitoring and planning is proposed. The techniques used are based on quantification through the use of different datasets (orthophotos and satellite images) of the areas covered by plastics used for crop protection. The study area chosen is a part of the Ionian Coast of Southern Italy, which includes the most important municipalities of the Basilicata Region for fruit and vegetable production. The use of geographical techniques and observation methodologies, developed in an open-source GIS environment, enabled accurate location of about 2000 hectares of agricultural land covered by plastics, as well as identification of the areas most susceptible to the accumulation of plastic waste. The techniques and the model implemented, due to its simplicity of use and reliability, can be applied by different local authorities in order to realize an Atlas of agricultural plastics, which would be applied for continuous monitoring, thereby enabling the upscaling of future social and ecological impact assessments, identification of new policy impacts, market searches, etc.