A system dynamics model of tellurium availability for CdTe PV

Abstract

The routine availability of key component materials has been highlighted as a potential constraint to both extensive deployment and reduction in production costs of thin-film photovoltaic (PV) technologies. This paper examines the effect of material availability on the maximum potential growth of thin-film PV by 2050 using the case of tellurium (Te) in cadmium telluride (CdTe) PV, currently the dominating thin-film technology with the lowest manufacturing cost. The use of system dynamics (SD) modelling allows for a dynamic treatment of key Te supply features and prospects for reductions in PV demand via material efficiency improvements, as well as greater transparency and a better understanding of future recycling potential. The model's projections for maximum Te-constrained CdTe PV growth by 2050 are shown to be higher than a number of previous studies using static assumptions-suggesting that a dynamic treatment of the resource constraints for CdTe inherently improves the outlook for future deployment of this technology. In addition, the sensitivity analysis highlights certain complex correlations between the maximum potential CdTe growth by 2050 and the rated lifetime of PV modules as well as the reported size of global Te resources. The highest observed sensitivities are to the recovery rate of Te from copper anode slimes, the active layer thickness, the module efficiency and the utilisation rate of Te during manufacturing, all of which are highlighted as topics for further research.

Assessing Rare Metal Availability Challenges for Solar Energy Technologies

“…The question is more economical in nature, i.e., whether the price of tellurium is a sufficient incentive for higher recovery rates. In addition to copper mines, other geological reserves for tellurium exist, such as by-product in lead-zinc ores, primary tellurium mines, ocean crusts and sour oil and gas [65].…”

Critical Minerals and Energy–Impacts and Limitations of Moving to Unconventional Resources

“…In the case of tellurium, the annual availability is based on the amount of electrolytic copper production, from whose anode slimes the majority of tellurium is currently extracted [59]. The life of currently mined ore bodies which are processed using this technique is a key limitation on tellurium availability, which may call into question the higher estimates of some studies [58]. It has been argued elsewhere that the market dynamics of increasing demand should drive price incentives and therefore the better supply-side recovery of such metals [38]; however, the current study does not consider improved recovery or market forces explicitly, but uses the alternative supply-side models based on trend growth and peak estimations to provide the mineral supply curves.…”

“…The metals tellurium, selenium and indium are predominately produced as byproducts of copper, lead and zinc. Taking tellurium as an example, a wide variety of future production rates have been given by various authors, and are well reviewed by other authors [37,58]. Reviewed estimates of indium availability are 290-26,143 tpa annual production and 625-6000 t cumulative production (to 2020), while tellurium availability is 128-2000 tpa annual production and 5250-47,000 t cumulative production (to 2020) [37].…”

“…It is important to note that some estimates of annual production assume that all by-product material is available to the industry [38], which is theoretically true, but not yet economically or technically practicable. Other studies insist on the importance of ore body consideration [59] and find limitations to metal availability, while some do not consider this explicitly, rather looking at trends in changes of processing methods over time [58] and in this case did not find limitations.…”

Criticality Research in the Materials Community

“…3,4 For example, the most recent Department of Defense Strategic and Critical Materials report per the Strategic and Critical Materials Stockpiling Act uses material consumption, production, and projected future demand to determine the severity of material criticality. Similarly, in previous literature 1,[5][6][7][8][9] the material availability is determined primarily by physical scarcity. Scarcity research calculates static metrics, such as depletion time (a measure of how long known reserves will last, given current levels of extraction); although it is informative and useful, it can provide only limited resolution of the real and complex issues at hand.…”