MATERIAL CONSTRAINTS IN THE FUTURE DEVELOPMENT OF GREEN TECHNOLOGIES

In the transition towards a low carbon economy the so called “green technologies” are going to play a crucial role. Still, their deployment will imply a renovation in the energy sector toward using renewable sources and... [ view full abstract ]

In the transition towards a low carbon economy the so called “green technologies” are going to play a crucial role. Still, their deployment will imply a renovation in the energy sector toward using renewable sources and zero emission transport technologies. This renovation will require a huge amount of raw materials, some of them considered critical. Therefore, an assessment of the possible future constraints created by the raw material needs associated to green technologies has been undertaken. The methodology to carry out this analysis combines a bottom-up and a top-down approach. In the bottom-up approach, an assessment, on a global basis, of the reserves, resources and estimated production trends from 2016 to 2050 (assuming a Hubbert-like production trend) for each commodity has been carried out. In the top-down approach, the requirements of each commodity for manufacturing green technologies in the 2016-2050 time period have been assessed. With the information coming from both approaches, the intersection between future estimations of demand and production, when demand exceeds production, can be calculated to help identifying possible material bottlenecks.

The methodology has been applied to the world development of wind power, solar photo-voltaic, solar thermal power and light duty vehicles for the 2016-2050 time period considering the impact on 31 different raw materials. Six risk categories have been identified, from very high to medium risk level, according to the cumulative demand, current reserves and annual production. For 7 of the 31 minerals analyzed, the estimated demand for green technologies exceeds production before 2050, therefore creating a possible bottleneck. These materials are silver, cobalt, gallium, indium, lithium, molybdenum and tellurium. For instance, indium and tellurium, which are used in photo-voltaics and light duty vehicles, are elements with a very high risk of shortage as their bottlenecks are expected in 2033 and 2036 when using current resources estimations. Besides, the risks and bottlenecks here defined are based only on green technologies demand, but this could be accentuated if the demand of other sectors was considered.

Once the most critical materials have been identified, a further analysis has been made regarding what the future recycling rates should be to compensate or delay considerably the identified constraints. For instance, in the case of indium, the actual average recycling rate (recycled content) is 37.5%.  If this number increased 0.5% annually from 2016 to 2050, reaching 44.65% in 2050, the bottleneck would be delayed more than twenty years. This puts emphasis on how important it is to increase efforts in recycling and to increase the secondary production of minerals to meet the future demand. In summary, this analysis has pointed out that the dependency and availability of critical materials must be taken into consideration along with other factors when promoting Green technologies. This entails encouraging strategies that focus on the design of green technologies with lower requirements of raw materials (especially those that are critical) or investing in recycling technologies.