San Francisco, Oct 7 (IANS): A week after a tweet from engineers of Google's parent company Alphabet Inc indicating their plan to bring emergency connectivity to hurricane-battered Puerto Rico via internet-by-balloon "Project Loon", the US Federal Communications Commission (FCC) has given the company the green signal.

The FCC has given Alphabet permission to fly 30 balloons over Puerto Rico and the US Virgin Islands for up to six months, Wired.com reported late on Friday.

Alphabet's balloons will help replace the thousands of cellphone towers knocked down by hurricane-strength winds and provide voice and data service through local carriers to users' phones.

The FCC has provided consent to Alphabet's application, which included letters and emails from eight wireless carriers in Puerto Rico, for "Loon" to use their frequencies for disaster relief and to restore limited communications.

30 "Loon" balloons will float 20 kms above the earth in the stratosphere, relaying communications between Alphabet's own ground stations connected to the surviving wireless networks and users' handsets.

Each balloon can serve up to 5,000 square kms, so the fleet is expected to provide service over all of Puerto Rico and potentially parts of the US Virgin Islands.

"'Loon' needs to be integrated with a telco partner's network, the balloons can not do it alone," an Alphabet spokesperson was quoted as saying.

Alphabet has previously deployed "Loon" to provide emergency phone service in Peru following flooding there earlier this year.