The Ecological Scarcity Method
The Ecological Scarcity Method (ESM) is based on a concept of Müller-Wenk (1978), which intends to establish an ecologically-based internal accounting system. This accounting system provides ecological ledgers which record resource and emission flows in order to assess the environmental impact of a company and its products. Within this concept, the environmental impact assessment was conducted with so-called equivalent factors. (ibid.) These equivalent factors were developed further by Ahbe et al. (1990) in Switzerland to conduct an environmental impact assessment of packaging materials amongst others.
How to calculate eco-points
The Ecological Scarcity Method within Life-Cycle Assesments
Today, the ESM is used for the impact assessment within Life-Cycle Assessments (LCA) but also other studies conducting an environmental impact assessment. The main object within the ESM is a set of so-called country-specific ‘eco-factors’, which are multiplied with their corresponding resource and emission flows in order to determine the corresponding environmental impact. In addition, eco-factors enable transferring the various units of measurement from the resource and emission flows to one common unit of measurement – the ‘eco-points’ indicator. As a consequence, the environmental impacts of the resource and emission flows under consideration can be aggregated in one amount of eco-points, which in turn determines the severity of the total environmental impact. Thus, the higher the amount of aggregated eco-points, the higher is the environmental impact. (Frischknecht and Büsser Knöpfel, 2013)
The ecological Scarcity Method in Switzerland
Due to the comparably long history of available eco-factors, it is not surprising that the ESM has gained increased popularity in Switzerland. Hence, the concept of ecological scarcity is taught in Swiss schools and the eco-factors are used to explain the environmental impacts of personal consumption (BAFU, 2008). Within one school lesson, for instance, pupils are taught the difference in environmental impact of differently cooked and packaged beans. The environmental impact is expressed in the total amount of eco-points while visualised in form of ‘ecological shadows’, as expressed in the following figure:
Besides the application in schools, the Swiss government has implemented LCA studies with impact assessments based on the ESM in parts of its legislation. For instance, the Swiss Biofuels Life Cycle Assessmeent Ordinance requires a demonstration of positive environmental impacts of biofuels in comparison to conventional fuels (Frischknecht and Büsser Knöpfel, 2013).
Additional cases of application of the ESM in Switzerland deal with the external disclosure of companies in form of environmental and sustainability reports. For instance, the fast food chain Mc Donald’s expressed the environmental impact of its operations in Switzerland within its Corporate Sustainability Report in 2012 (see Figure 87) (McDonald’s Suisse Restaurants, 2012). Further Swiss companies as the producer of sanitar parts, the Geberit AG or advertising company, the APG|SGA SA use the eco-points indicator to express the environmental impact of their operations (Geberit AG, 2014; APG|SGA, 2012).
Ecological Scarcity Method for Germany
For application in environmental management of production sites of a German automotive company, an approach had been developed based on the ecological scarcity method (“eco-factor method”). However, this method is based on Swiss environmental targets and flows which is not adequate for site-specific assessment outside of Switzerland. In our study, we adapted the ecological scarcity method to German framework conditions. We compiled data and information in order to identify targets and flows from which we derived the necessary values to calculate eco-factors for Germany. Data as well as the methodological procedure for assessment of current and critical flows have been validated by involvement of the German environmental agency in the working process. From our work we provide a set of 20 eco-factors for Germany based on current official environmental targets and most up-to date data for environmental flows which all in all ensures the assessment tool to be reliable and meeting the stringent conditions of a corporate use.
Ecological Scarcity Method in Japan (www.treeze.ch)
Recent discussions and debates of biomass utilization in Japan necessitate conducting life cycle assessment (LCA). There are no impact assessment methods suitable for the assessment of agricultural production and biomass utilization in Japan from a comprehensive perspective. In 2004 eco-factors for Japan (JEPIX) were calculated based on the former version of Swiss ecological scarcity 1998. Unfortunately, the adapted version did not take into account, for example, ammonium and nitrate emissions, which are crucial in assessing agricultural production and biomass utilization.
The existing Japanese eco-factors are completed and updated according to the method of ecological scarcity 2006. This work was in part supported by a grant from the Ministry of Agriculture, Forestry and Fisheries of Japan (Rural Biomass Research Project, BUM-Ca2300).
Ecological Scarcity Method for Thailand
Thailand has been promoting biofuel production and consumption to substitute transport fuels in order to utilize domestic resources and contribute to greenhouse gas (GHG) mitigation. This study adopted a Life Cycle Impact Assessment (LCIA) method using “distance-to-target” approach based on the Swiss Eco Scarcity method. It is developed by using Thailand’s current situation of pollutants emissions and natural resources use in line with the three related national policy goals i.e. GHG, primary energy and freshwater resources; the Eco-Factors are 1.6, 0.13 and 1.9 Thai Eco Point (TEP) per kgCO2e, MJ NRE-eq and m3 in respective units. These were used for an LCA comparison between cassava-based ethanol and palm oil-biodiesel with their fossil fuel counterparts on an energy basis. The LCA results indicate both biofuels have lower impacts than the equivalent fossil fuels and the main contributor is GHG emissions from biofuel production. The sensitivity analysis also indicated the given policy related to freshwater and GHG influence the biofuel benefits. Therefore, the strong policy and technical options in energy production are still required for sustainable biofuels following the government intention.