Use of Bitcoin causing huge carbon dioxide emissions: Study

BERLIN: The use of Bitcoin — a popular virtual currency — emits over 22 megatonnes of carbon dioxide annually, comparable to the total emissions of cities such as Las Vegas and Vienna, a study has found.
Researchers from Technical University of Munich (TUM) in Germany carried out the most detailed calculation of the carbon footprint of the Bitcoin system to date.
For a Bitcoin transfer to be executed and validated, a mathematical puzzle must be solved by an arbitrary computer in the global Bitcoin network.
The network, which anyone can join, rewards the puzzle solvers in Bitcoin.