The ECB's move on Wednesday to establish a pilot that could lead to a digital currency for the 20 countries that use the common currency, making it the first heavyweight Western central bank to formally forge ahead, could become a global blueprint.

Supporters say CBDCs will modernise payments with new functionality and provide an alternative to physical cash, which seems in terminal decline.

But questions remain why CBDCs represent an advance, with uptake low in countries such as Nigeria that have adopted them, as well as protests against the ECB’s plans, showing public concern about snooping.

Commercial bankers fret about the costs and possible deposit bleeds as customers could move money into central bank accounts, while developing countries worry that an easily accessible digital dollar, euro or yuan could cause havoc in their systems.

'WHAT IS MONEY?'
The ECB's plan "is a very big deal, and a lot of the rest of the world is watching this closely", said Josh Lipsky, who runs a global CBDC tracker at the Atlantic Council.

"It is one of the biggest central banks, so if it comes up with answers to the privacy and cyber security issues and the ability to use it offline, it will be a very influential."

Central banks were spooked into action five years ago when Facebook floated plans for a breakaway currency. Now, though, policymakers have yet to fully persuade many why CBDCs are needed.

Fabio Panetta, the ECB Executive Board member overseeing the bank's digital euro work, said it would help "future-proof" the currency and reduce what he called an over-reliance on the payment systems of U.S.-based credit cards.

But experts are scratching their heads.

"It's not yet clear what the thing is that could be done with a retail CBDC that couldn't also be replicated with commercial bank money," said Barclays' managing director of advanced technologies, Lee Braine, who has been involved in some of the Bank of England's digital pound projects.

"You are potentially breaking some of the singleness of money" he said, flagging the risk of a two-tier system if CBDCs are allowed different functionality or data disclosure rules than bank accounts.

"This all comes down to, what is money?"

DEFINING A GLOBAL STANDARD
A key unknown is whether the U.S. Federal Reserve or Bank of Japan will launch retail CBDCs.

India could be a more effective test environment than China because, while each Asian giant has more than 1 billion people, India has a far more open economy.

In contrast, Canada and some others appear to be tapping the brakes, while most of those already using CBDCs are seeing very little interest.

Data this month from the Bahamas, which launched the world's first digital currency in 2020, showed personal transactions of its SandDollar were down 11% in the first seven months of the year while wallet top-ups had plunged four fold.

An International Monetary Fund (IMF) paper in May described public adoption of Nigeria's eNaira as "disappointingly low", with 98.5% of wallets never even used.

"The current adoption level of eNaira has been reflective of the early stage of CBDC awareness," the country's central bank said in a written response to questions, adding it had been "consistent" with expectations.

Bo Li, an IMF deputy managing director, said this month the multilateral lender was helping dozens of countries with CBDC plans and would soon publish a how-to guide. It is building what it calls its XC platform, meant to process or "settle" CBDCs transactions.

The Atlantic Council's Lipsky said this, along with the technology choices the ECB and India make, could start defining a worldwide standard, as VHS did early in videotape era.

"The overarching question" about developing CBDCs, Lipsky said, "is how does this improve the financial system? That it really what it's all about".

Reporting by Marc Jones in London; Additional reporting by MacDonald Dzirutwe in Lagos; Editing by William Mallard