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Vertical farming is emerging as an effective measure to grow food in buildings and can increase food production in urban areas in a more sustainable manner. This study presents a comprehensive environmental assessment of food production in an integrated rooftop greenhouse (i-RTG) – an innovative vertical farm consisting of a rooftop greenhouse connected to a building – and considers rainwater, residual heat (energy), residual air (CO 2 ) and food from an industrial ecology perspective. This synergistic connection preserves resources and improves conditions in the greenhouse and the building. The goal of the study is to show the feasibility of the system and to calculate the environmental impacts from its whole life cycle, from infrastructure to end of life, by comparing these impacts with those of conventional production. The results show that the system is feasible and produced 30.2 kg/m 2 of tomato over 15.5 months. The synergy with the building allows the cultivation of winter-fall crops without supplying heating and maintained an average temperature 8 °C higher than that outdoors. Moreover, rainwater was used to irrigate the crops, reducing consumption from the water supply network by 80–90%. The environmental assessment showed that the operation of the i-RTG has more impacts than the infrastructure (structure of the greenhouse, rainwater harvesting system and equipment) due to the use of fertilisers, which account for 25% of the impacts in four of the six impact categories studied. Regarding the infrastructure, the greenhouse structure and rainwater harvesting system of the building have substantial environmental impacts (over 30% in four of the six impact categories). Comparison with a conventional greenhouse demonstrates that the i-RTG has a better environmental performance, showing between 50 and 75% lower impacts in five of the six impact categories (for instance, 0.58 kg of CO 2 equivalent per kg of tomato vs. 1.7 kg), mainly due to the reduced packaging and transport requirements. From this study, it was concluded that optimisation of the amount of infrastructure material and management of the operation could lead to even better environmental performance in future i-RTG projects. [ABSTRACT FROM AUTHOR]

Abstract: Until now, few studies had focused on the environmental impact of the construction phase of a drinking water transport and distribution network (DWTDN). Using the life cycle assessment (LCA) methodology, this article compares the environmental impact of pipes made of different materials as constructive solutions for the DWTDN. Two pipe diameters (90 and 200 mm) commonly used in small to medium-sized cities are analysed. The results show that polyvinyl chloride (PVC), high density polyethylene (HDPE) and low density PE have similar environmental impacts in the case of 90 mm pipe diameter. In the case of 200 mm pipe diameter, ductile iron (DI) and glass fibre reinforced polyester show higher environmental impacts than HDPE and PVC, which in the case of DI are between 3 and 11 times higher than those of HDPE for all the midpoint impact categories. Regarding the different construction phases, installation has a higher percentage of environmental impact for 90 mm pipe diameter (40–68% for HDPE in all the impact categories) than for 200 mm pipe diameter (24–57% for an HDPE) due to the difference in the amount of material required for the manufacture of the pipe. The assessment methodology was applied to calculate the environmental burdens derived from a case study. The impact of the different elements of the case study network has been added to obtain the global impact. The potential reduction of the environmental impacts of the case study has been calculated substituting the whole actual network by less impacting constructive solutions. A potential reduction of between 6 and 16% of the impact has been found for the case study, although the savings might be greater in networks with greater abundance of more impacting pipe materials such as DI. This methodology allows the improvement of the network and the design of more eco-efficient DWTDN. [Copyright &y& Elsevier]

Abstract: A cement manufacturing company located in Catalonia (Spain) has upgraded its cement production plant. The new cement production line (L6) has replaced the former lines (L3, L4 and L5) which have been operating for 30 years. The new line production L6 has been designed and constructed taking into account the best available techniques (BAT) for the cement industry. The significant improvements achieved with the new plant are related to the energy efficiency of the new kiln system which represents less amount of fossil fuel and to less emission to the atmosphere per kg of clinker produced. Life-cycle assessment (LCA) methodology has been used for the quantification and evaluation of the environmental impacts of the new production line (L6) considering the designed goals proposed and those achieved at first trimester of 2011 compared to the former production lines. To reduce uncertainty this manuscript presents a cradle-to-gate life-cycle assessment of both scenarios. Analysis using SimaPro 7.2 software shows that new production line (L6) provides a significant reduction of the environmental impact for global warming (5%), acidification (15%), eutrophication (17%) and cumulative exergy demand (13%). The damage assessment also confirmed that new production line (L6) reported a significant reduction impact for the human health (11%), ecosystem quality (11%) and resources (14%) damage compared to the former lines. [Copyright &y& Elsevier]

There is great potential to reduce the environmental impact of the building sector, which is now an area of immense importance, through the optimisation of construction materials and components. This study assesses both the design and the construction of Concrete Deep Foundations (CDFs), which are widely used in construction, from an environmental perspective considering the following variables: (i) grade of prefabrication, i.e., fully cast in situ, partly prefabricated, and fully prefabricated; (ii) compressive strength of cast-in-situ concrete; and (iii) building design codes, i.e., current Spanish codes (EHE-08 and CTE), Eurocode with the Spanish annexes, and Eurocode with the United Kingdom annexes. In addition, the results of Dynamic Load Tests (DLTs) and the economic cost of several CDFs are evaluated. Geotechnical and structural designs of CDFs are carried out along with their life-cycle assessment. Some of the main findings include: (i) partially and fully prefabricated CDFs and conducting DLTs reduced the environmental impact in most categories (by up to 44% for global warming emissions) compared to the fully cast-in-situ CDFs, although they were 12–37% more expensive; (ii) changing the compressive strength of the concrete (in piles and cap) in fully cast-in-situ CDFs from 25 to 35 MPa reduced the environmental impact by up to 14–17% in all categories and economic costs by up to 12%; and, (iii) CDFs with bored piles resulted in the lowest environmental burden when designed with Eurocode and UK annexes (11–31% less impact), as did CDFs with driven piles designed with current Spanish codes (11–18% less impact). The study variables and sensitivity analysis showed a significant effect on the results and should be considered in future construction, research, and building codes. • The prefabrication of Concrete Deep Foundations (CDFs) reduces environmental impact and increases the economic cost. • Increasing the compressive strength of concrete reduces environmental impact and cost. • Conducting Dynamic Load Tests on driven piles reduces environmental impact and cost. • CDFs with bored piles are environmentally better designed with Eurocode with UK annexes. • CDFs with driven piles are environmentally better designed with current Spanish codes. [ABSTRACT FROM AUTHOR]