The objective of the economic and environmental assessment in DRIVE4EU was to identify, quantify and assess the most important economic and environmental impacts and benefits of natural rubber and PEF production from Rubber dandelion (Taraxacum koksaghyz, TKS). Figure 1 shows the DRIVE4EU system in comparison to the conventional reference system.
The results of economic calculation including CAPEX and OPEX are total costs per year and specific costs per kg total products (comprising 0.4 kg NR and 0.6 kg PEF). Calculation was done for 8 cultivation (different countries, planting methods with low or high density, with irrigation or not) and 3 biorefinery (rubber production 5, 12 and 120 kt per year) concepts. Results show a significant influence of the costs for cultivation on the total costs. Energy and investment costs are the cost drivers in the biorefinery. To show future possibilities of DRIVE4EU system input data for the cost calculation are assumed like higher yield of roots, higher rubber content, higher efficiency in the biorefinery thus reducing costs for energy and auxiliary materials. Figure 2 shows a comparison of results for a selected cultivation and biorefinery concept for current status and future 1 and future 2 scenario.
The LCA of the DRIVE4EU system shows that due to the current state of technology the environmental effects of the DRIVE4EU system are higher than for the conventional reference system. The main influencing factors of the environmental effects (GHG emissions with and without land use change, cumulated primary energy demand, acidification, ozone creation potential, water consumption, area consumption) are the cultivation and harvest process step especially fertilizer, plant protective agents and diesel. The share of cultivation and harvest lies approx. between 75% and 90% of the total GHG emission. Comparing to natural rubber from Hevea tree the cultivation and harvesting of Rubber dandelion is completely different; the aim in DRIVE4EU is to have as much mechanical work as possible, harvesting latex from Hevea trees results in a lot of manual work. The analysis of future scenarios showed, that the environmental effects of the DRIVE4EU system could be reduced significantly with possible future improvements (GHG emissions see Figure 3). Following future improvements are assumed e.g., higher yield, higher rubber content, less fertilizer and plant protective use, lower energy demand in refinery.
Figure 1: Scheme of DRIVE4EU system in comparison to the conventional reference
Figure 2: Comparison of specific costs of base case with future 1 and future 2 scenario
Figure 3: Comparison of base case with future 1 and future 2 scenario