Metrics (potentials, potency factors, equivalency factors or characterization factors) are available to support the environmental comparison of alternatives in application domains like process design and product life-cycle assessment (LCA). These metrics typically provide relative insights into the implicit concern associated with chemicals, emissions and resource consumption in the context of human health, ecological health and resource depletion. The approaches used to derive the metrics range in their site-specificity, complexity, comprehensiveness, sophistication and uncertainty. It is therefore often necessary to consider the use of more than one approach within the context of a given impact category to help support a decision. In this paper we outline some of the strengths and weaknesses of available approaches in the commonly considered categories of global warming, tratospheric ozone depletion, tropospheric ozone (smog) creation, eutrophication/nutrification, acidification, toxicological impacts and resource depletion.
The SPOLD Information System (SIS) was released in January 2000. This poster gives a quick survey of the system.
The main problem involved in valuing resource depletion is that the effect or damage occurs in the future and therefore our assessment depends on our assumptions on how this future looks like.
Resource depletion may not in itself be a problem if there is adequate time for humanity to develop technologies to deal with an imminent depletion, i.e.:
· technologies for harvesting adequate amounts of sustainable energy, and/or
· technologies (including societal arrangements) for a voluntary regulation of the size of the human population so that it becomes stable and adjusted to a size which can be sustained by the actual size of the resource basis.
The problem is that these technologies may not be developed in time to avoid damage during the transition period.
Market-based system delimitation may reduce the need for data collection in life cycle assessments (LCAs) without compromising reliability. Rather than including all potential suppliers and customers (e.g. in a weighted average), the market-based procedure allows the data collection to be reduced to those suppliers and customers, which are actually affected by a studied product substitution. Furthermore, the uncertainty on the market data will most often determine the level to which the overall uncertainty of the LCA can be reduced, thus providing a limit for what process data it is meaningful to collect.
Co-production (the combined or joint production of two or more products from the same process or system) has been seen as presenting a problem to the system modelling in life cycle assessment, and the traditional solution has been co-product allocation (the partitioning and distribution of the environmental exchanges of the co-producing process or system over its multiple products according to a chosen allocation key) in parallel to cost allocation. Compared to this traditional solution, system expansion according to ISO 14041 provides a more realistic modelling of the actual consequences of product related management decisions. Through a number of examples, including recycling of steel and aluminium, it is demonstrated how co-product allocation can be avoided in practice. The example of platinum-group metals is used to illustrate how system expansion may sometimes be used as a justification for economic allocation.
Denne rapport præsenterer et livscyklus-baseret klima-fodaftryk (Carbon footprint) for genbrug af hittegodscykler, istandsat og leveret af Baisikeli ApS i salgbar stand i Chimoio, Mozambique.
Bekendtgørelse om hittegods § 4. stk. 2. siger at ”Hittegods, der er værdiløst eller af så ringe værdi, at det ikke kan bære omkostningerne ved auktionssalg, kan destrueres eller udleveres til almennyttige eller velgørende formål, når der er forløbet 4 uger fra indleveringen til politiet.”
Hittegodscykler bliver i dag bortskaffet som metalskrot og genbrugt ved omsmeltning. Baisikeli ApS sender i stedet cyklerne til Mozambique hvor de sættes i stand og sælges lokalt. Herved erstatter cyklerne mindre holdbare nye cykler, primært fremstillet i Indien.
Formålet med klima-fodaftrykket er, at vurdere CO2;besparelsen ved at genbruge cyklerne i Mozambique i forhold til at omsmelte dem i Europa. Vurderingen er foretaget på 8000 hittegodscykler, som er den gennemsnitlige mængde, der årligt sendes til skrot fra Københavnsområdet.
