As important as the internal combustion engine has been for societal progress, it is also a major contributor to pollution that damages human health and carbon emissions that help drive the climate crisis. Close to 30% of U.S. carbon emissions come from transportation, and 95% of transportation uses fossil fuels.
One element of a potential remedy would be to power vehicles with hydrogen fuel cells, which emit only water vapor. However, this sustainability solution has an ironic, built-in aspect that’s unsustainable: The catalysts necessary to draw power from hydrogen involve rare and expensive metals such as platinum. In amounts used for today’s technology, widespread adoption would require quantities of these metals beyond what humankind can source.