A massive growth in demand for new sustainable technologies — like rechargeable batteries — has resulted in skyrocketing demands for certain materials. Some of these materials, like silicon and copper, are relatively abundant, easy to source and pose no real bottleneck for manufacturers of sustainable energy technology. Other materials, like neodymium, cobalt and lithium, raise concerns about ethical resource extraction and whether or not supply will be able to keep up with rapidly growing demand for sustainable energy.

Here are the materials demanded by the sustainable energy boom — and the difficulties that suppliers may face.

Difficulties of Sourcing Sustainable Materials

The shift toward sustainable energy has created a sudden spike in demands for rare materials that weren't previously used as often. This shift has caused issues for manufacturers, who are struggling to adapt their supply chains and source these rare materials.

Take, for example, neodymium, a rare earth material used in the manufacture of magnets — a necessary component for wind turbines. Despite its classification, neodymium isn't particularly rare — the problem with neodymium is where the element occurs. About 85% of the world's stores of neodymium are located in China. Smaller mines exist around the world — in Burundi, Malawi and even California — but these mines don't have the equipment needed to process the neodymium into a usable form. Most neodymium stops in China for processing before it can be used in sustainable energy projects.

The concentration of these mines and processing plants causes two problems for manufacturers. First, transportation and processing are huge bottlenecks that slow down production and can even create emissions. Second, manufacturers have little to no control over the environmental effects caused by neodymium mining — as in cities like Batou, where the dirty business of neodymium mining and processing has pumped significant levels of pollutants into the local water supply.

At the same time, some materials necessary for sustainable energy aren't so exotic. Copper, for example, has a role to play in almost every kind of sustainable energy production. It's found in abundance all along the rocky and mountainous west coast of these Americas as well as around the Gulf of St. Lawrence in Canada. Sustainable energy companies have options when it comes to copper, allowing them to optimize their supply chains — or change suppliers if they find that the working conditions at the mine their copper comes from aren't safe.

Other construction materials needed for sustainable projects, like aluminum — used to build lightweight structures — are familiar to manufacturers and typically easier to source.

Ethical Concerns of Sustainable Materials

Many materials necessary for sustainable energy projects are either rare or highly localized where they naturally occur. This setup creates supply chain issues — and can also lead to ethical issues as businesses operating in impoverished countries employ unethical methods to extract as much rare material as possible to meet growing demand for sustainable energy in more developed nations.

For example, some experts are concerned about the environmental effects of mining lithium — a major component in rechargeable lithium-ion batteries. Much of the world's lithium supplies come from water-starved regions of South America. The lithium mining process is water-intensive, and water used in the mining process is typically contaminated with pollutants. As a result, lithium mining can both drain these regions of much-needed water and — without proper environmental controls — lead to contamination of local water sources.

There are also ethical concerns raised by the mining of cobalt in the Democratic Republic of the Congo (DRC). Cobalt is sourced almost entirely from the DRC, where some businesses — left unchecked by government or international regulations — employ child laborers. Some cobalt mines are even controlled by insurgent militias.

Meeting the Rising Demand for Sustainable Energy

The rise of new sustainable technologies has created a surge in demand for materials. Some of these materials, like copper and aluminum, aren't particularly difficult to source and can often be supplied by mines in countries with strong safety regulations. Other materials, like cobalt and lithium, are harder to source, and it may be difficult for manufacturers to purchase these materials from only ethical suppliers.

In the near future, this crisis may deepen as the demand for sustainable energy technology increases.