The latest polymer £10 note came out in September 2017, at which point the old one was taken out of circulation.
What happens to all of those old bank notes? In short, they have to be destroyed.
This is to prevent old banknotes re-entering circulation and to prevent people swapping these withdrawn banknotes for new ones over and over again.
830 million bank notes worth over £11 billion are destroyed in the UK every year!
They’re usually destroyed because they are poor quality, or because they are no longer legal tender.
Until 1990, notes were burned and the heat helped warm up the Bank of England! However, that’s not very good for the environment or very efficient.
The Bank upgraded its equipment in the early 1990s and moved away from that method.
In the early 2000s, they started to recycle old bank notes by composting them!
From 2011, the majority of the Bank’s paper note waste has been recycled in this way and used as a soil improver for agriculture.
Next time you enjoy a carrot or potato from your local farm, it could have grown in millions of pounds worth of soil – literally!
However, because plastic isn’t compostable, the new plastic and polymer notes will be turned into tiny little pellets before being transformed into new plastic items like plant pots.
Despite this being quite energy intensive, the polymer £5 and £10 notes are the greenest yet.
The Carbon Trust has said that the carbon footprint of a new £10 polymer banknote is 8% lower than the old £10 paper banknote.
That’s looking at the full life cycle of emissions including from their production, use, and final disposal.