Speaking at the Australian Payment Summit last week, RBA governor Philip Lowe said it is hard to see "so-called crytopcurrencies" ever being commonly used for everyday payments.
Mr Lowe said the "current fascination" with cryptocurrencies, which has seen the price of bitcoin surge from US$950 in January 2017 to US$19,1140 this morning, feels like "speculative mania" rather than an endorsement of bitcoin as a practical currency.
"The value of bitcoin is very volatile, the number of payments that can currently be handled is very low, there are governance problems, the transaction cost involved in making a payment with bitcoin is very high and the estimates of the electricity used in the process of mining the coins are staggering," Mr Lowe said.
"When thought of purely as a payment instrument, it seems more likely to be attractive to those who want to make transactions in the black or illegal economy, rather than everyday transactions.
"So the current fascination with these currencies feels more like a speculative mania than it has to do with their use as an efficient and convenient form of electronic payment."
He did not rule out the eventual emergence of an "efficient and low-cost" electronic payment in the future.
However, in the understated language of a central banker, he said, "There is a certain attraction of being able to make payments from funds held in prudentially regulated accounts that can earn interest."