SAN DIEGO (CNS) - It looks as if a new NFL football stadium in San Diego really could cost $1 billion or more.

A study released Wednesday by the National University System Institute for Policy Research confirms previous estimates that a new stadium in San Diego will cost at least $725 million - and more likely more than $1 billion.

The costs are controversial because public funds may be used to complete the project.

Last month, the chairman of a task force that's developing a financing plan for a National Football League-quality stadium in Mission Valley estimated the price tag would be between $700 million and $1.5 billion.

"Developing a financing plan for a new stadium requires estimating the amount of money that will be required," said NUSIPR President Erik Bruvold. "This report seeks to help with that effort - providing a rough estimate for what San Diego will need to spend to construct a stadium similar to those going up in other NFL-cities."

Bruvold said the average cost of the last 20 NFL stadiums to be built was $618 million.

However, when adjusted for inflation and given the reality of construction costs in Southern California, the number increases to $898 million.

Bruvold said NFL franchises are clamoring for state-of-the-art facilities that can attract fans away from their "large TVs, dedicated viewing areas in their homes and who have a multitude of viewing options available to them," which just add to the costs.

Amenity-heavy stadiums built in Dallas, New Jersey and Santa Clara - and under construction in Atlanta and Minneapolis - would cost $1.7 billion if built in Southern California, he said. The five most recently built facilities - excluding Dallas and New Jersey - would cost $1.4 billion in 2020, according to Bruivold.

He said the San Diego price tag by 2020 could reach $1.7 billion.

The financing plan from the task force is expected to be made public next month.