When it comes to cars, it’s not just what’s under the hood that matters — it’s what’s on the scale.

According to a new book, Critical Mass: The One Thing You Need to Know About Green Cars, a vehicle’s damage to the planet can be boiled down to a simple formula: mass multiplied by distance traveled. EVs tend to be around 700 pounds heavier than comparable combustion vehicles which exacerbates tire pollution and road wear issues, creating significant environmental impact beyond just tailpipe emissions.

Listen in as we sit down with authors Nick Molden, founder and CEO of Emissions Analytics, and Felix Leach, Associate Professor of Engineering Science at the University of Oxford, to discuss their idea for a weight-based tax system that future-proofs tax revenue while nudging consumers toward lighter, more sustainable vehicles.

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