MUMBAI: Unique Identification Authority of India ( UIDAI ) former chairman Nandan Nilekani today said with new digital payment systems like BHIM and UPI in place, around 15-20 per cent of the country's personal consumption expenditure will become digital in next one year from the current level of 5 per cent."With new technologies like Bharat Interface for Money (BHIM), Unified Payment Interface (UPI), Unstructured Supplementary Service Data (USSD), Aadhar micro ATM and Aadhar merchant pay, there will be significant push towards digital transactions because the infrastructure we will have is completely different from anywhere else," Nilekani said at a Federal Bank event."My own estimate is that today about 5 per cent of personal consumption expenditure in India is digital, and I am very confident that next year or so, as much as 15-20 per cent of our consumption expenditure will be digital."Nilekani today launched uPOS, a solution where merchants can accept payment using UPI, from Federal Bank.He said the usage of new digital payments technologies will reduce cash in the economy but increase the cash in the banking system.Nilekani said banks will also witnessed changes from point of view of the transactions fee."Historically, banking system has seen high value transactions with high transaction costs. They will now have to move to the world where the transaction value would be low, and the fee will be low, but the number of transactions would multiply many times," he said.He further said the core banking systems of the banks will now have to deal with very high level of real time transactions which they are not used to."Banks will have upgrade their core banking system to deal with this volume," he said.Nilekani said while demonetisation has had it challenges, it has accelerated the role of the country building the world's most advanced digital financial infrastructure."What demonetisation did was that it gave a sense of urgency to complete all the technical and regulatory impediments to create this (digital payment infrastructure)," he said.According to Nilekani, debit and credit cards will continue to be the payment modes as there is a section of the market that will need cards."Cards are very important for global travellers. But if everything goes well then the UPI transactions will quickly overtake the cards transactions. There will more of them, maybe lesser value but there will be many more of them," he said.