SACRAMENTO, Calif. -- Just a few years ago, NBA commissioner Adam Silver had a hard time envisioning seeing this day come.

He stood outside Sacramento's new, state-of-the-art downtown arena Thursday and welcomed Kings fans to the home opener for a franchise many believed was on its way out of town just over three years ago.

"I think it's a borderline miracle from where we were in 2013 to be here in 2016, a year earlier than they originally pledged to have an arena done," Silver said before the Kings hosted San Antonio in the first regular-season game at the Golden 1 Center. "To be done, to be here on opening night with the building completely finished with strong local ownership, it's everything a league could hope for."

The idea seemed far-fetched back in the spring of 2013 when the Maloof family was poised to sell the team to a group of Seattle investors seeking to move the franchise to the Pacific Northwest.

The new, 17,500-seat Golden 1 Center is the first professional sports venue powered completely by solar energy. AP Photo/Rich Pedroncelli

But tech mogul Vivek Ranadive stepped up to buy the team for $534 million and keep it in California's capital city with a new arena that Silver calls the new standard in the NBA.

The 17,500-seat arena is the first professional sports venue powered completely by solar energy, will save about a million gallons of water a year compared to a typical venue of its size, was built with recycled material from the mall that stood at the site before construction began and will get 90 percent of its food and beverages from within 150 miles.

It became the first indoor venue to receive LEED Platinum certification, the highest level of recognition for environmentally conscious buildings.

There are other features such as the NBA's first 4K ultra HD video board, providing a picture four times clearer than HD, and an in-arena app that allows fans to control the temperature at their own seat.

The arena is part of a $1 billion development project that includes 1.5 million square feet of mixed-use property that will have a hotel, restaurants, retail shops, offices and condos. About $500 million in outside investment is also expected in the area.

"These are true modern-day town halls," Silver said. "You can see from the smiles on the fans' faces as they were walking in, there was sort of a collective 'Wow!'"

Among the most unique features are the airplane hangar doors that can be opened to turn the venue into an indoor-outdoor arena. The team tested them out for parts of three preseason games and saw no measurable differences in temperature, humidity or wind on the court and would like to be able to open the doors during games eventually.

The league wants to do additional tests and consult with other teams before coming up with a protocol for when the doors can be open.

"Because it's so new, we want to make sure we get it right," Silver said. "It will probably be a few more weeks. Our hope is it will be done well before this season will be over."

Silver also said there is an opportunity for an All-Star Game to come here, saying the team has presented a plan to have visitors stay on cruise ships in the Sacramento River delta to make up for a lack of hotel rooms.

"Sacramento has beaten the odds so many times before," Silver said. "Initially at first blush, it was 'We'd love to come here but you don't have enough hotel rooms.' But there is a true can-do attitude here in Sacramento."