The state-run firm is testing sustainability of technology in three villages in Alwar district of Rajasthan.
At present, the state-run telecom giant operates wi-fi hotspots at 14 locations across Lucknow, Kanpur and Varanasi.
The firm will install 4G base towers in the existing GSM sites, which means there will be no additional expenditure on towers
The state-run telecom company had planned to set up 2,500 wi-fi hotspots in 250 locations at a cost of Rs 500 crore.
'Zero site' can be used as a Wi-Fi hotspot, street light and camera and radio units can be hidden inside pole or underneath
For MTNL, debt has been accrued due to a payment of Rs 11,098 crore for broadband wireless access and 3G spectrum charges to the government in June 2010
BSNL was allocated 3G spectrum in 2100 Mhz and the it paid the auction determined price to the government