Powered by Materials: the energy-material configuration of electric vs. combustion vehicles
Out now, in the journal Resources, Conservation, and Recycling!
Energy-Material Cycles: A materials-based perspective of vehicle energy systems
This paper addresses a blind spot in environmental impact assessment. Many have studied the material intensity of conventional versus electrified technologies, but most still frame these comparisons in terms such as dirty versus clean and non-renewable versus renewable. Because all energy-yielding processes require material degradation, such static dichotomies can be misleading. It’s why the ecological realities of battery supply chains – the ore mining and processing bonanza, the working conditions, and the environmental effects – now make for front page news and enraging best-sellers such as Cobalt Red.
We have to investigate the ecological merit of electrification on more honest terms, and this paper represents an attempt to do so, with clearly drawn system boundaries and rigorously compiled data. The focus is, surprise, cars!
What do we find? That all three EV systems investigated are less material-intensive than their combustion-based corollaries.
This result is well-aligned with the push to electrify. But the assessment method prompts a novel shift of perspective on the energy transition: batteries are fuel materials. They are primary energy carriers that degrade, just like the gasoline & oxygen that react in a combustion engine, degrading to CO2 and water. This method allows us to communicate results not in terms of dirty vs clean or renewable vs non-renewable, but simply as different configurations for turning earth-material into human activity. Here's the Energy-Material Cycle accounting system, in diagram form:
All vehicles are powered by materials. Those materials come from abiotic stocks (orange), such as minerals, or renewable stocks (green) such as plant material. Materials are “charged”, or upgraded, to Primary stocks (blue) and “discharged”, or downgraded, to byproducts.
