Marianne Wesnæs

Data quality management for life cycle inventories - An example of using data quality indicators

Abstract A formal procedure for data quality management in life cycle inventory is described. The procedure is applied to the example of an energy inventory for 1 kg rye bread. Five independent data quality indicators are suggested as necessary and sufficient to describe those aspects of data quality which influence the reliability of the result. Listing these data quality indicators for all data gives an improved understanding of the typical data quality problems of a particular study. This may subsequently be used for improving the data collection strategy during a life cycle study. To give an assessment of the reliability of the overall result of a life cycle inventory, the data quality indicators are transformed into estimates of the additional uncertainty due to the insufficient data quality. It is shown how a low data quality can both increase the uncertainty and change the mean value. After assigning additional uncertainties to all data in the study, a calculation of the uncertainty of the overall result is made by the use of simulations. The use of default estimates of additional uncertainties is suggested as a way to both simplify and improve the procedure.

Environmental improvement potentials of meat and dairy products

The report is a scientific contribution to the European Commissions Integrated Product Policy framework, which seeks to minimise the environmental degradation caused throughout the life cycle of products. This report first presents a systematic overview of the life cycle of meat and dairy products and their environmental impacts, covering the full food chain. It goes on to provide a comprehensive analysis of the improvement options that allow reducing the environmental impacts throughout the life cycle. Finally, the report assesses the different options regarding their feasibility as well as their potential environmental and socioeconomic benefits and costs. The report shows that meat and dairy products contribute on average 24% to the environmental impacts from the total final consumption in EU-27, while constituting only 6% of the economic value. The main improvement options were identified in agricultural production, in food management by households (avoidance of food wastage), and related to power savings. When all environmental improvement potentials are taken together, the aggregated environmental impacts (external costs) of meat and dairy products may be reduced by about 20%. How to obtain EU publications Our priced publications are available from EU Bookshop (http://bookshop.europa.eu), where you can place an order with the sales agent of your choice. The Publications Office has a worldwide network of sales agents. You can obtain their contact details by sending a fax to (352) 29 29-42758.

Environmental Consequences of Future Biogas Technologies Based on Separated Slurry

This consequential life cycle assessment study highlights the key environmental aspects of producing biogas from separated pig and cow slurry, a relatively new but probable scenario for future biogas production, as it avoids the reliance on constrained carbon cosubstrates. Three scenarios involving different slurry separation technologies have been assessed and compared to a business-as-usual reference slurry management scenario. The results show that the environmental benefits of such biogas production are highly dependent upon the efficiency of the separation technology used to concentrate the volatile solids in the solid fraction. The biogas scenario involving the most efficient separation technology resulted in a dry matter separation efficiency of 87% and allowed a net reduction of the global warming potential of 40%, compared to the reference slurry management. This figure comprises the whole slurry life cycle, including the flows bypassing the biogas plant. This study includes soil carbon balances and a method for quantifying the changes in yield resulting from increased nitrogen availability as well as for quantifying mineral fertilizers displacement. Soil carbon balances showed that between 13 and 50% less carbon ends up in the soil pool with the different biogas alternatives, as opposed to the reference slurry management.