We are halfway through lunch when Sophia Hamblin Wang rummages in her bag and plonks on the table a couple of non-distinct blocks: one a white cube the size of a square tennis ball, the other a thin rectangular grey chunk of what looks like a slice of classic 1970s breeze block.

These unimposing objects are tiny samples of carbon capture and utilisation. And right now they are winging their way to Glasgow as concrete – quite literally – examples of how technology, not taxes, can save the world from the worst of climate change.