For a start, the technical difficulties of reintroducing a national currency, reprogramming computers and vending machines, minting coins and printing notes are huge (three years' preparation was needed for the euro).

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The average cost of printing new notes is far below the face value of the notes.

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Printing Treasury Notes and getting other countries to make stuff in exchange is, of course, one way of cutting CO2 emissions.

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There is the cost of printing and pressing new notes and coins.

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Home printing is fine for occasional prints, she notes, while high-street printing makes more sense for larger runs, such as holiday photos.

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When Reserve Bank inventories of fit cash run down to certain levels because of the destruction of unfit notes, the Reserve banks order new notes from the Bureau of Engraving and Printing, a division of the Treasury Department.

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Canadian Banknote is asking about Dollars 2.9m (Pounds 1.71m) to print the notes and is offering to build the factory as a joint venture, which would recoup its costs by printing money for other republics and nations.

CENTERFORSECURITYPOLICY: Center For Security Policy