The Ecological Backpack
20 Apr 2021
Every product carries an ecological backpack from manufacture through to disposal. It is filled with the weight of all materials consumed during the product’s entire lifetime. In view of the increasing global shortage of resources, a calculation model such as the ecological backpack is vital in terms of raising awareness of the use of resources.
A certain quantity of raw materials is consumed at each stage of a product’s lifetime – whether production, transport, usage or disposal. The ecological backpack represents the resulting total weight. However, this model can not only be used to put a figure on the ecological impact of products but also on the consequences of specific services, one’s own lifestyle or entire national economies. The heavier the ecological backpack, the more harmful the consequences for the environment.
The ecological backpack should not be confused with the ecological footprint. Rather than the total weight of consumed raw materials, the ecological footprint symbolises the surface area required to cover the demand for resources. The surfaces considered include forests, pasture and arable land as well as ocean surfaces. The ecological footprint is also used for the annual calculation of Earth Overshoot Day. Last year it fell on 22 August. This means that the global population is using natural resources 1.6 times faster than they can regenerate.
The MIPS formula as the basis for the model
The ecological backpack model is based on the MIPS formula (Material Input per Service Unit) developed by the Wuppertal Institute. The total of all raw materials moved and extracted during the lifetime of a product is divided by the product use. The use of a car, for example, would be the number of kilometres one can drive from purchase to the day the vehicle is scrapped. The material input comprises both biotic and abiotic raw material, water, air and erosion. The Institute’s resource calculator can be used to analyse one’s own lifestyle and its impact with regard to elements of daily living such as housing, consumption, nutrition, leisure, mobility and holidays. The calculation acts as a basis for providing recommendations on how to use resources more efficiently.
The ecological backpack of a smartphone
Would you ever have thought that a mobile phone weighing just 80 grams carries a backpack weighing over 75 kilograms? This high figure is mainly the result of the processing of metals such as copper. Roughly 3.5 kilograms of natural resources are moved to produce 10 grams of copper, which is installed in smartphones in the form of cables and printed circuit boards. Besides the extraction of raw materials, usage is a main contributor to the life cycle assessment followed by production and disposal.
Big differences are possible here, depending on the material concerned. For example, producing one kilogram of paper requires 15 kilograms of resources: in other words, the input is 15 times greater. On the other hand, the input for aluminium production is 85 times greater and for gold a massive 500,000 times greater.
Criticism of the ecological backpack model
Despite analysing the entire life cycle of a product, the ecological backpack does not consider all environmental impact. For example, critics observe that, although the assessment of cotton production takes the production input of pesticides into account, it fails to consider the ecological consequences of their use. In some circumstances, the input of air or water may also be excluded from the calculation.
By focussing on the weight of raw materials consumed, certain factors are evaluated differently than they would be when measuring the CO2 footprint, for example. This means that assessment of the same product, a used car for instance, can be positive in terms of resource consumption but much more negative when taking CO2 emissions into consideration. Each assessment model is based on a different standard. Therefore, in order to achieve maximum objectivity, multiple assessment methods have to be used at the same time and the various results compared. For example, in addition to the already mentioned ecological backpack and (CO2) footprint, the water footprint or virtual water model can also be applied.
Despite the weaknesses discussed here, the ecological backpack is a suitable tool for assessing one’s own use of resources and the impact of consuming specific products. As with the ecological footprint, special computers can be used to specify how environmentally-friendly or damaging one’s own behaviour is and what measures can be taken to improve it. The efficient use of scarce resources, greater awareness of our consumption behaviour and returning products to the material cycle by refurbishing or recycling are necessary steps in conserving our planet’s finite resources.