|Characterisation Method Name:|
|contributions to resource consumptions|
|Principal Method Name:|
|EDIP: normalisation of known reserves|
Consumption of materials, ancillary substances and fuel are expressed in the inventory as primary intake of resources directly from nature, i.e, minerals, water, biomass etc. Resources are expressed as pure substances and not as ore.
Definition of reserve
The magnitude of the reserve is that fraction of the resource which can presently be exploited economically. Both known and estimated reserves of known occurrence are included.
Changes in geological information, technology, the price of extraction and production and the price of the raw material can affect the estimate of the reserves. Reserves beyond the capabilities of current production facilities may well exist (World Resources, 1990, 1992; BP, 1992).
The concept of reserve base covers that fraction of the resource which fulfils the requirements of ore grade, quality, quantity and depth defined by current practice within mining and production, but which is not necessarily profitable to extract. The reserve base can be significantly greater than the reserve.
The reserve base is usable in connection with weighting of resource consumption from the point of view of scarcity, but data for the reserve base are typically lacking.
Resource indicators are expressed as:
WR(j) = RC(i) / RES(PE),
WR(j) is the product's normalized consumption of resource (j) expressed as the fraction of the known reserve per person in 1990
RC(j) is the consumption of resource (j) per product, i.e., the total consumption in the product system for the life of function unit.
RES(PE), is known reserves per person
Oil and gas
Data for annual production and reserves of fuel are given in BP (British Petroleum) (1992). If the magnitudes of the 1987 reserves are compared with data in World Resources (1990), differences of between 9% and 12% are found.
Data for production and reserves are from BP (1992). It should be noted that World Resources (1990) gives reserves of coal twice as great as given by BP (1992)
World resources (1992) was used as the resource of production data and the magnitude of reserves. The data are originally from the US Bureau of Mines, which publishes data for the USA and all other countries in the world if the data are reliable. The data are based on government bureaus for statistics and minerals the UN and the literature. Other information is also included to enable comparability of the data. The most significant source is World Mineral Statistics, published by British Geological Surveys. Their goal is to present the latest information directly from the countries which produce and trade in minerals, rather than to offer data from other organizations which work with global mineral statistics. Estimates are made in those cases where there are no data for production and trade.
Zn. Cu. Ni. Sn. Pb
Comparisons with figures for the 1989 productions of zinc, copper, nickel, tin and lead in World Resources (1990) and British Geological Survey (1991) reveal differences of between 0 and 4%.
Information for iron is found only for production and reserves of iron ore (World Resources, 1992).
Production data for pig iron were used for iron (British Geological Survey, 1991). Comparison of productions of iron ore and pig iron enables calculation of an average iron content of 55% in the ore. The difference between production data for iron ore given in British Geological Survey (1991) and in World Resources (1992) is 6%. According to Sorensen (1989), production of iron today is based on ores with high iron content. Magnetite contains 72.4% iron, haematite 69.9%, limonite 60%, and siderite 49% iron. The average iron content of the reserves is ca. 43%. World Resources ( 1992) gives reserves of 151,000 million tons.
Information for aluminium is found only for production and reserves of bauxite (World Resources, 1992).
World Resources (1992) gives only extraction of bauxite and consumption of aluminium. As consumption of aluminium corresponds to the production of primary aluminium given by British Geological Survey (1991), the figures for consumption are used in the normalization. The relative aluminium content for bauxite in 1990 is thus 17,878,000/109,118,000 = 0.16. According to Serensen (1989), bauxite contains 40-60% Al2O3, which gives an aluminium content in bauxite of 21-32%. If it is assumed that bauxite reserves contain 16% aluminium, the aluminium content of the reserves is ca. 21,800 million tons x 0.16 = 3,488 million tons.
The extraction of manganese ore and the content of manganese is given in British Geological Survey (1991). The total production of manganese in 1989 was 9,476,272 tons and the ore grade of the ore was 38%.
For such renewable resources as water and wood, it is necessary to consider whether the specific resource is renewed at a higher rate or whether it matches consumption. There is no official definition of the supply horizon for renewable resources, and it is here defined as:
Supply horizon = known reserves/(Annual consumption- annual regeneration)
If the specific resource is renewed at a rate which corresponds to or is higher than consumption, the supply horizon is infinite.
The normalized value for renewable resources is also found by dividing the normalized value by the supply horizon.
Annual global percolation to the groundwater is 40,673 km3. By comparison, consumption is 3,240 km3
Denmark possesses water reserves of 11 km3 and consumption is 1.46 km3 (BP, 1992). In principle the weighted data should therefore be zero, corresponding to an infinite global supply horizon. The picture may, however, differ locally, and fresh water must therefore always be considered locally.
Total global production of wood is 3,425,613,000 m~ per annum, with 2,139,000 m3 per annum in Denmark. There are no data for the regeneration rate for wood, but net forest clearing is 0.3% (World Resources, 1992). Globally, this means that the supply horizon for wood is 333 years, but local conditions may be very different.
Wood should therefore also be considered locally, but as it was not possible to establish a database for this in the EDIP program, the global supply horizon is used.
|Michael Hauschild and Henrik Wenzel (1998): Environmental assessment of products Vol. 2 Scientific background London Chapman & Hall|
|Geographical range is Denmark and EU|
|Characterisation Parameter||Category Indicator||Impact Indication Principle||Aspect||Substance||Quantity||Unit||Notes|
|CFactor||Natural gas consumption||EDIP/1997||