Life-cycle phosphorus use efficiency of the farming system in Anhui Province,Central China

The rapid increase of phosphorus (P) use in farming has raised concerns regarding its conservation and environmental impact. Increasing the P use efficiency (PUE) is an approach to mitigating these adverse impacts. In this study, we applied substance flow analysis (SFA) to establish a life-cycle P use efficiency model to determine the life-cycle PUE of the farming system used in Anhui Province in 2011, which is typical of the agriculture practiced in central China. Based on this model, the P flows and PUEs of five subsystems were identified and quantified: crop farming, crop processing, livestock breeding, rural living, and urban living. The three largest P flows were found in the crop farming and livestock breeding subsystems; it can therefore be concluded that these subsystems have substantial impacts on the entire farming system. In contrast, the PUEs of crop farming, rural consumption, and livestock breeding subsystems presented the three lowest PUEs (58.79%, 71.75%, and 76.65%, respectively). These results were also consistent with the finding that the greatest P losses occurred in crop farming and livestock breeding. Consequently, the study proposes that great potential exists for increasing PUEs in the farming system of Anhui, and several of the most promising measures could be combined for improving PUEs. Finally, the study assesses data quality and presents a sensitivity analysis for use in interpreting the results. The study also shows that improving PUE and decreasing P losses in farming systems through improved nutrient management must be considered an important issue, and this study represents valuable experience in resource conservation and agricultural development in China.     

System dynamics model for analyzing effects of eco-design policy on packaging waste management system

EU's long-term objective is to become a recycling and resource effective society, where waste is utilized as a resource and waste generation is prevented. A system dynamics model was developed to analyze the policy mechanisms that promote packaging material efficiency in products through increased recycling rates. The model includes economic incentives such as packaging and landfill taxes combined with market mechanisms, behavioral aspects and ecological considerations in terms of material efficiency (the packaging material per product unit, recycled fraction in products). The paper presents the results of application of various policy instruments for increasing packaging material efficiency and recovery rate and reducing landfilled fraction. The results show that a packaging tax is an effective policy instrument for increasing the material efficiency. It ensures the decrease of the total consumption of materials and subsequent waste generation. The tax helps to counteract a rebound effect, which, as identified by the analysis, can be caused by reduced material costs due to eco-design. The model is applied to the case of Latvia. Yet, the elements and structure of the model developed are similar to waste management systems in many countries. By changing numeric values of certain parameters, the model can be applied to analyze policy mechanisms in other countries.     

Environmental resource footprinting of drug manufacturing: Effects of scale-up and tablet dosage

The formulation and scale-up of batch processes is one of the major challenges in the development of pharmaceutical dosage forms and at the same time a significant resource demanding process which is generally overlooked in environmental sustainability assessments. First, this paper proposes general trends in the experience curve of cumulative resource consumption of pharmaceutical tablet manufacturing of PREZISTA^® 800 mg through wet granulation (WG) at four consecutive scales in both R&D and manufacturing environments (resp. WG1 = 1 kg/h, WG5 = 5 kg/h, WG30 = 30 kg/h and WG240 = 240 kg/h). Second, the authors aim at evaluating the environmental impact from a life cycle perspective of a daily consumption of PREZISTA^® 2× 400 mg tablets versus the bioequivalent PREZISTA^® 800 mg tablet which was launched to enhance patient compliance. Environmental sustainability assessment was conducted at three different system boundaries, which enables identification, localization and eventually reduction of burdens, in this case natural resource extraction. Exergy Analysis (EA) was used at process level (α) and plant level (β) while a cradle-to-gate Exergetic Life Cycle Assessment (ELCA) was conducted at the overall industrial level (γ) by means of the CEENE method (Cumulative Exergy Extraction from the Natural Environment). Life cycle stages taken into account are Active Pharmaceutical Ingredient (API) production, Drug Product (DP) production and Packaging. At process level (α), the total resource extraction for the manufacturing of one daily dose of PREZISTA^® (800 mg tablet) amounted up to 0.44 MJ_ex at the smallest scale (WG1) while this amount proved to be reduced by 58%, 79% and 83% at WG5, WG30 and WG240 respectively. Expanding the boundaries to the overall industrial level (γ) reveals that the main resource demand is at the production of the Active Pharmaceutical Ingredient (API), excipients, packaging materials and cleaning media used in DP production. At the largest scale (WG240) the use of cleaning media during DP production contributes considerably less to the total resource extraction. Overall, the effect of scale-up and learning on resource consumption during DP production showed to possess a power-law experience curve y = 2.40 * x^−0.57 when shifting from WG1 (smallest lab scale) to WG240 (industrial manufacturing). Tablet dosage (2× 400 mg versus 1× 800 mg) did not significantly affect the absolute environmental burden. However, the relative contribution of resource categories did change due to the different production technology. It could be concluded that in meeting social and economic demands by launching the PREZISTA^® 800 mg tablet, no trade-off in environmental burden occurred. On the long term, future research should strive to take into account R&D processes and all services related to pipeline activities taking place prior to market launch and eventually to allocate impacts to the final product.     

Thoughts concerning the economic valuation of landscapes

The incorporation of economic thinking into the valuation of landscapes is still relatively new. It is an approach that yields valuable new insights and can help with prioritizing the use of scarce resources to improve and/or preserve landscapes. This paper explores and discusses the uses and limitations of economic valuation of landscapes from market failure, policy process, and theoretical and philosophical perspectives.     

Energy efficiency and appliance’s characteristics considered prior to purchase: Differences and similarities between the United Kingdom,Germany, Portugal,Greece, Poland,Spain and Italy

This article reports country differences in the consumer’s most considered characteristics when choosing electrical appliances, including but not restricted to the energy efficiency aspect. A survey was performed to store customers from 7 countries: the United Kingdom; Germany; Portugal; Greece; Poland; Spain; Italy. Results showed consistency between countries in the top three characteristics considered: cost; quality; and a balance between price and quality. Differences were found for reported environmental attitudes and behaviours, purchase motives, and store employees evaluation. The results may support national policies and store level energy efficiency interventions. Specifically, they can provide input for store employee’s training, in persuading customers towards the purchase of energy efficient appliances.     

An experimental apparatus for testing biodiesels based on a CFR engine—setup and validation with different methyl ester blends

A cooperative fuel research (CFR) engine was modified and instrumented in order to control operating conditions and to measure engine parameters and in-cylinder pressure diagrams. Aiming at the comparison of different alternative fuels, an experimental procedure was defined, including cetane number (CN) evaluation and the definition of engine operating quantities in different working points, for fixed levels of compression ratio (CR) and injection advance. An investigation was made considering several blends of methyl-esters of rapeseed oil (RME) and of a mix of vegetable oils (VOME) with conventional diesel oil. The defined experimental procedure was applied to assess CN, engine brake thermal efficiency (bte) and exhaust emissions. Results show that the biodiesel content has a positive influence on soot emissions, with strong reduction, while thermal efficiency and NO_X emissions are negatively affected, which can be justified taking into account fuel properties and changes in combustion process. As observed outcomes are generally in line with those presented in literature, the facility proved to be a suitable tool for basic investigations on alternative fuels to be used in specific applications.     

Efficiency enhancement in solar air heaters by modification of absorber plate-a review

This paper outlines a complete review on modifications made on the absorber plate of solar air heaters in order to improve the turbulence and heat transfer rate, thereby efficiency. Corrugated sheets, fins, extended surfaces, wire mesh, porous medium, etc., are a few of the modifications used. Most of such alterations in the absorber plate resulted with an increase in efficiency but associated with drawback of increased pumping power due to raising friction factor. Pumping power is considered here as a predominant comparison parameters of various solar air heaters with different absorber plate in terms of effective efficiency.     

Experimental investigation of a 250-kW turbine organic Rankine cycle system for low-grade waste heat recovery

An organic Rankine cycle (ORC) is generally used for converting low-grade heat into electricity. In this study, an extensive literature survey was conducted to identify current research gaps on experimental ORC systems. Specifically, there is limited experimental data and limited details on thermal and expander efficiencies of ORC systems. In order to address these gaps, the objective of this study included developing a turbine ORC with a power output exceeding 50 kW and thermal efficiency exceeding 8% for a heat source temperature < 120°C. The experimental results indicated that the system achieved a net power output of 242.5 kW and a thermal efficiency of 8.3% (the highest value for a turbine ORC system for the heat source temperature below 120°C). Thus, the study addressed the gaps identified in the research area of ORCs.     

Variability and Trends in Runoff Efficiency in the Conterminous United States

Variability and trends in water‐year runoff efficiency (RE) — computed as the ratio of water‐year runoff (streamflow per unit area) to water‐year precipitation — in the conterminous United States (CONUS) are examined for the 1951 through 2012 period. Changes in RE are analyzed using runoff and precipitation data aggregated to United States Geological Survey 8‐digit hydrologic cataloging units (HUs). Results indicate increases in RE for some regions in the north‐central CONUS and large decreases in RE for the south‐central CONUS. The increases in RE in the north‐central CONUS are explained by trends in climate, whereas the large decreases in RE in the south‐central CONUS likely are related to groundwater withdrawals from the Ogallala aquifer to support irrigated agriculture.     

Institutional Constraints on Cost‐Effective Water Management: Selenium Contamination in Colorado's Lower Arkansas River Valley

Ground and surface water selenium (Se) contamination is problematic throughout the world, leading to harmful impacts on aquatic life, wildlife, livestock, and humans. A groundwater reactive transport model was applied to a regional‐scale irrigated groundwater system in the Lower Arkansas River Basin in southeastern Colorado to identify management practices that remediate Se contamination. The system has levels of surface water and groundwater Se concentrations exceeding the respective chronic standard and guidelines. We evaluate potential solutions by combining the transport model with an assessment of the cost to employ those practices. We use a framework common in economics and engineering fields alike, the Pareto frontier, to show the impact of four different best management practices on the tradeoffs between Se and cost objectives. We then extend that analysis to include institutional constraints that affect the economic feasibility associated with each practice. Results indicate that although water‐reducing strategies have the greatest impact on Se, they are the hardest for farmers to implement given constraints common to western water rights institutions. Therefore, our analysis shows that estimating economic and environmental tradeoffs, as is typically done with a Pareto frontier, will not provide an accurate picture of choices available to farmers where institutional constraints should also be considered.