San Francisco Mayor Gavin Newsom said the United States is still "playing in the margins" of the greentech opportunity.

During a speech at the Cleantech Forum in his city Tuesday, Newsom said he’d like to see elected officials push the technology envelope, such as by supporting plug-in hybrids and zero-emission vehicles rather than just regular hybrids, which he called "last year’s excitement."

(Earlier this month, the city converted three city-owned Toyota Prius hybrids into plug-in hybrids and said it would order up to 250 plug-in hybrid vehicles if they were commercially available.)

Insist on real government action, Newsom advised the cleantech crowd at the San Francisco event.

"If you hear another [official calling for emissions] 25 percent below 1990 levels by 2025, you should walk out of the room," he said, saying such announcements are just public-relations events at this point. "Don’t ever believe politicians when they [cite] environmental numbers. Verify everything."

Newsom said it’s crucial to hold elected officials "to results, not rhetoric."

"Otherwise, this is overexuberance," he said. "We may be getting ahead of ourselves if we can’t grow the market.

As an example, he referred to the U.S. energy bill, signed into law in December, that raised fuel-economy standards for vehicles for the first time in more than 30 years, calling for vehicles to average 35 miles per gallon by 2020.

"CAFE standards -- people are jumping up and down," he said. "Give me a break. … In five or six years, maybe we’ll catch up with China."

Newsom said he hopes San Francisco, which Popular Science Magazine named one of America’s greenest cities this week, will have a carbon tax in place by the end of this year.

"People have talked about it; nobody has done it," he said. "We’re going to do it."

British Columbia last week said it would introduce a carbon tax (see Policy Roundup: British Columbia Curbs Carbon).

Newsom in December said he hoped San Francisco voters would approve the tax, which is still being developed and which would be defrayed by a matching decrease in the payroll tax, when it appears on the ballot in November.

Among many other initiatives, San Francisco has set environmental goals of lowering carbon-dioxide emissions 20 percent below 1990 levels by 2010 and reaching carbon neutrality in the city government by 2020.

The mayor in January proposed a ban on T12 fluorescent light bulbs in favor of T8 fluorescent bulbs -- which are 40 percent more energy efficient, according to the city -- as part of a plan to reach those goals.

San Francisco also has adopted green building standards, which will require increasing levels of certification for new buildings and -- in a few years -- also require certification for remodels, Newsom said.

Earlier this month, Newsom issued a directive to measure and reduce the environmental impact of information and communication technology within municipal government buildings.

And in spite of all its green measures, San Francisco’s economy is doing well. "Revenues have never been stronger," he said.

Newsom said he believes supporting cleantech via public policies is "one of the easiest things a government can do."

He said he attends conferences where other elected officials say they think it’s amazing that San Francisco is aiming to recycle 75 percent of its waste by 2010. "Big deal," he said. "If we had zero waste, that would be amazing."

And it’s not enough to take action within the scope of the governments themselves, such as making public vehicle fleets cleaner, Newsom said. Governments also need to do far more to encourage greentech in the private sector, he said.

"Municipal [action] is great, but it’s only a few percentage points; it’s not even in the margin of error," he said.

Newsom also nodded to geothermal, tidal and wave-energy technologies.

"Mother Nature’s been laughing at us as we’re drilling for oil, drilling for gas, drilling for coal," he said. 

Newsom didn’t mention that tidal and wave energy have faced a gamut of challenges and setbacks, including technology and cost issues, that can’t only be attributed to a lack of government support (see Pulling Energy from the Sea and Wave Energy Finds a Buyer).

He encouraged the cleantech industry to continue pushing its innovation, passion and action.

"It’s time to get serious," he said. "Yes, you will make money, but you also will change lives."

Newsom’s advocacy of greentech-friendly policies unsurprisingly found favor with the conference attendees. 

"We need bigger and better policies," said John Boesel, CEO of WestStart – Calstart, a nonprofit that develops green transportation technologies, after the speech.

Boesel said he particularly liked the idea of substituting a carbon tax for an employment tax.

"It’s a great idea, an idea that should be taken nationally," he said. "Now we’re taxing a good -- employment -- and not a bad -- carbon. We should be taxing a bad and not a good. I expect this idea will be going national in five to 10 years, but I’d like to see it in two to three years."