1 Institute of Chemical Engineering, Biotechnology and Environmental Technology, Faculty of Engineering, SDU2 Institute of Chemical Engineering, Biotechnology and Environmental Technology, Faculty of Engineering, SDU
The dilemma of resource scarcity is not new but its focus has changed from fossil fuels depletion to the mineral resource constraints of clean energy technologies. In order to be independent of fossil fuels we need broad implementation of clean technologies such as wind turbines, photovoltaic, electric and hybrid vehicles. However, the emergence of these technologies may also be constrained by decreasing availability of resources. In the last few years, this problem has received high attention by the research academia, policy makers and the corporate sector and all of these sectors have tried to develop a method to identify and assess the critical resources at different levels . The issue of understanding resource criticality and identifying critical resources is interdisciplinary and should be researched in a collaborative effort having material scientists, geologists, product designers and environmental engineers work together to develop a robust understanding of criticality and an ability to navigate technological development through potential future bottlenecks. An illustrative case of technological and corporate vulnerability to supply constraints and radical price increase is the direct drive wind turbine being today dependent on the Rare Earth Elements Neodymium and Dysprosium in the magnets. The recent dramatic increase in permanent magnet market price due to the development in Rare Earth Elements prices late 2011  tended to threat the business case of the direct drive wind turbine and was a wake-up call to rethink the strategy of wind turbine development. Which resource consumptions are the most critical and how critical are they in the alternative technological solutions? Are we back to the gearbox turbine technology or redesigns of the direct drive? This paper presents a methodological approach to resource criticality assessment on the technology level and it compares alternative wind turbine technologies. It involves the trade-off between higher Dysprosium and Neodymium consumption in the direct drive turbine and higher Copper consumption of the gearbox turbine and it strives to quantify and assess this trade-off.  Graedel, T.E., Barr, R., Chandler, C., Chase, T., Choi, J., Christoffersen, L., Friedlander, E., Henly, C., Jun,C., Nassar, N.T., Schechner, D., Warren, S., Yang, M and Zhu, C. 2012. Methodology of Metal Criticality Determination. Environ. Sci. Technol: 46 (2). pp: 1063–1070.  Apelian, D. 2012. Material’s science and Engineering’s pivotal role in sustainable development for the 21st century. MRS Bulletin: 37(4). pp: 318- 323.