Fueling the future: Overcoming the barriers to market development of renewable fuels in Germany using a novel analytical approach

Germany has set ambitious targets for reducing greenhouse gas (GHG) emissions, namely by 65% until 2030 (compared to the 1990 level) and achieving climate neutrality by 2045. Although GHG emissions have decreased in most sectors, the transport sector has experienced failed reduction attempts. Renewable fuels are promising sustainable fuel alternatives that can replace current market-dominant fossil fuels to reduce GHG emissions. However, the market development of renewable fuels is hindered by various economic, environmental, technical, regulatory, and social barriers. Using a novel holistic approach, this study aims to analyze the market development barriers for renewable fuels in the German transport sector. First, a novel extension to the decision making trial and evaluation laboratory (DEMATEL) method is proposed using the Type-2 Neutrosophic Numbers (T2NN), which is improved by the K-means algorithm. Second, the maximum mean de-entropy algorithm is applied to convert the results of T2NN-DEMATEL into input for interpretive structural modeling (ISM). Next, a case study is conducted to analyze the impacts of barriers on different transport modes using the T2NN-based additive ratio assessment. Extensive sensitivity analyses are conducted to measure the impacts of different factors under different circumstances. The obtained results indicate that insufficient renewable energy policies and regulations, the lack of coordination in the supply chain, and high technology conversion challenges are the most significant barriers. Moreover, road and maritime transport are affected more than the aviation and rail sectors by the market development barriers.