Industry needs to team up with cities to battle climate change, Cisco Systems Chairman and CEO John Chambers told local government leaders on Wednesday.

Saying his views had changed from just five or six years ago, the head of the world's largest network builder cozied up to officials from municipalities around the world at the Connected Urban Development Global Conference in San Francisco.

"It is hugely important to have supportive government," Chambers said.

The conference, co-hosted by Cisco and the city and county of San Francisco, focused on what cities can do to reduce greenhouse gas emissions and encourage their residents to do the same. As an example of what might help, the city unveiled a "green" bus equipped with Wi-Fi and with screens that can tell riders where they are, when they'll reach their destination and how much they're reducing their greenhouse gases by taking the bus. That will encourage them to ride more often, the city said. Officials from Seoul also discussed traffic-reduction initiatives at the conference, and Amsterdam representatives talked about an efficiency standard for data centers.

Cities should play the key role in tackling climate change because they consume 75 percent of the world's energy and produce 80 percent of its emissions, Chambers said.

Rather than coming up with solutions one by one, pioneering cities should work with each other and private industry to create a "replicable blueprint" for making urban centers friendlier to the environment, Chambers said. Cisco's Connected Urban Development initiative will start with a few cities, including the three represented at the conference, and deliver knowledge and best practices to many more cities over time, he said. He called for cities to tap into social-networking technology -- which Cisco has been rapidly adding to its portfolio -- to bring together parties that traditionally haven't worked together.

Though it wasn't on display at the conference, Cisco's Telepresence high-definition virtual meeting technology played a key role in Chambers' speech. Cisco has used Telepresence units for 75,000 meetings since its debut just over a year ago, and in the process has slashed travel, helping to cut Cisco's annual greenhouse gas emissions per employee by 10 percent, Chambers said. One air trip produces the same emissions as 98 Telepresence sessions, he said. Meanwhile, Chambers said, he was able to slash the company's budget by US$150 million thanks to the new technology.

"Corporate social responsibility is just plain good for business," Chambers said.

Cisco isn't just pushing green technology to save money and the Earth. San Francisco's green bus, created by Cisco, is equipped with a Cisco router to link onboard Wi-Fi with outdoor 3G (third-generation) mobile data. Cisco also envisions the bus using its IPICS (Internet Protocol Interoperability and Collaboration System) technology, which unifies many public-sector radio technologies through an IP network.