Treasury Secretary Janet Yellen issued a warning Monday about the dangers that bitcoin poses both to investors and the public. Elon Musk's Tesla recently made a substantial purchase and has said it will accept bitcoin for transactions. "I don't think that bitcoin … is widely used as a transaction mechanism," she told CNBC's Andrew Ross Sorkin at a New York Times DealBook conference. It's an extremely inefficient way of conducting transactions, and the amount of energy that's consumed in processing those transactions is staggering." The electric consumption used in the process leaves an annual carbon footprint equal to the nation of New Zealand, according to Digiconomist.
