Even though the supply of all chemical elements in the universe is infinite with regards to the needs or uses for them known by the human race, nonetheless the limited supply of tellurium present at or near the earth's surface, that part of the world in which we do and can mine and recover it, is very limited.
The amount of tellurium that can be obtained, not the total amount produced, by any one user, such as First Solar (FSLR), is the limiting factor to their production rate.
Investors in high technology device manufacturing need to determine if such devices depend critically, that is they cannot be made otherwise, upon any specific metal. If they are dependent then investors need to ask the manufacturer how it plans to secure its supply of that critical material.
Unfortunately it has become common in the rapid development of our technological society to simply assume that, providing one is willing to pay then, any material will always be available.
This is not true, because the production rate of some of the most critical natural resources used in the latest high tech devices is limited due to either:
- The material, such as tellurium, is the byproduct of another material, so that the production of the byproduct is entirely dependent on the production rate of the mother natural resource, or
- The cost of producing the critical material as a primary product is prohibitive, or
- We do not know how to recover additional quantities of the critical material either technologically or economically in any practical way.
The largest manufacturer of cadmium telluride thin film photovoltaic cells has said that its use of tellurium is between 50 and 100 metric tons per gigawatt of solar energy conversion from its devices. The open question therefore is "can tellurium's production rate sustain any more than a small contribution by cadmium telluride based solar cells to the future demand for renewable energy?"
The manufacturer says that they are able to obtain much more tellurium than is currently believed by geologists and mining engineers to be available.
Investors are betting that the company's statements are correct.
If the company is wrong then cadmium telluride thin film photovoltaic cells are going to be a niche product at best as the capacity to manufacture them becomes resource limited to the point where their production is capped.