How is it structured?
The study of Zah (2007) showed that the most important steps in the production chain of biofuels are the agriculture and the production of the biofuels. This is valid for the emissions of greenhouse gases as well as in the evaluation of the overall environmental impacts with different methods. The data entry for the questionnaire is structured as shown in Figure 1.
The relevant parameters in the agriculture on the input side are the use of fertilizers, pesticides and land transformation of tropical rain forest or other soils with high carbon stocks. On the emission side, dinitrogen oxides, nitrate, phosphate and heavy metal emissions are relevant for the results of the assessment. These emissions are to some extent dependent on the input of fertilizer but also on climate and soil conditions. In the processing step, the results depend mostly on the energy demand of the process and the allocation factors.
The questionnaire allows therefore entering the inputs of fertilizer and pesticides in the cultivation step. It also requires some basic data like crop yield or geographical information, which are used for the calculation of emissions in the agricultural step. In the processing step, data on energy efficiency and chemicals have to be entered.
In addition to the environmental aspects of the life cycle of biofuels, the Swiss ordinance sets requirements also on social aspects (MinöStV 2008). As the assessment of the social factors follows other rules as the assessment of environmental impacts, this part of the SQCB questionnaire aims mainly at increasing the awareness of the user for this aspect.
In general, the navigation within the SQCB follows the structure as shown in Figure 4. The entry of the data is downstream, i.e. from the entry of the basic data to the cultivation and processing up to social criteria. However, except for the basic data, which is a precondition for all other data entries, the data can be entered as preferred by the user. The navigation is implemented as shown in Figure 2.
The user can navigate using both the navigation bar on the left hand side and the navigation bar on the top. After the user has entered the data required, all data entries are validated meaning that the SQCB checks if (i) all required data is available and (ii) the data entered is correct. The user gets a feedback on which data should be corrected / completed. If all data is correct, the user can calculate his results.
In general, help buttons are placed below the input field. Using this button, the user can get additional information which explains and eases the data entry.