Kuenssberg: Why 'boomer' Schwarzenegger won't wait to tackle climate change

"I myself am a boomer! I'm, like, horrible!"

There's something a bit unexpected about one of the most famous people on the planet using what's become a term of abuse about themselves instead of choreographed gushing about their latest project.

But Arnold Schwarzenegger's path in life has been unexpected, and unprecedented: celebrity bodybuilder; Hollywood action hero; Republican Party governor of California; climate campaigner.

Technically, he is indeed one of the post-war generation - the baby boomers, much mocked for not moving with the times.

But when we meet to talk at his glossy climate conference in Vienna where everything, including the hot dogs, is vegan, he teases himself to make a big point.

Politicians must move much faster, he believes, to preserve the planet for the generations to come. And Schwarzenegger's strong belief is that the technology exists to crack down on emissions but the "boomers" might miss the chance.

This is the man who - as governor of California - in 2006 enacted a landmark climate change bill, the California Global Warming Solutions Act, which established greenhouse gas emission targets for the state.

He told me: 'We have to change with the times. I would not want to drive, except maybe for fun, a car that is 50 years old.

"I don't want to make investments that were really cool 50 years ago - you would lose your shirt today if you made those investments. We have to change with the technology, it's as simple as that."

And his message applies to environmental activists too, calling on campaigners not to try to block development as a solution to climate change, but to push for a different kind.

He said it's "the same with the environmental movement, we have to get out of the mode of stopping every project from being built. We've got to go and build, build, build all these green projects." In other words, hurry up!

His challenge is exactly the question that's being put to our governments too. It's true the UK has had a decent record on renewable energy compared with other countries.

Energy Secretary Grant Shapps boasted last weekend that "we're ahead of the game because of the level of renewables that we've got coming into our system right now".

But there is anxiety about that progress stalling, just when the scale of what's needed becomes clear.

Only two onshore wind turbines were built in England last year, for example.

The number of heat pumps that are being installed is woefully behind its ambition - the target is for 600,000 low-carbon heat pumps to be installed every year within five years; currently it's only 50,000 - less than 10%.

The boss of the battery firm that went bust, Britishvolt, claimed the government foot-dragging was partly to blame for it going under - although that was denied by ministers.

And National Grid, not exactly prone to hyperbole, said "unprecedented" and "transformative" change was needed right now.

The statistics they published this week about what's needed by 2030 illustrate that in a pretty jaw-dropping way. They calculate the UK needs:

Labour's shadow climate change secretary Ed Miliband accuses the government of a "failure of ambition and action" when it comes to clean power.

"The planning ban on onshore wind alone is costing £180 for every family, and a government asleep at the wheel has allowed grid delays to grow to more than a decade," he says.

Labour, he promises, will lift the ban on onshore wind generation and "be builders, not blockers, for the clean power we need".

And when you talk to industry insiders, the frustration with the government's pace is obvious.

One source told me that "the government isn't accelerating - it's not doing much more than was agreed at Carbis Bay" - an international summit two years ago - even though the need is becoming more and more obvious and the conflict in Ukraine has made reliance on fossil fuels precarious in a different way.

Another, frustrated with the difference between the government's rhetoric and reality, told me Grant Shapps was "all hat, no cattle".

The differences are more obvious as the US has introduced an enormous plan for subsiding firms moving to use or produce green energy, the Inflation Reduction Act. And the EU has brought in its Net Zero Industry Act.

For now, the UK government is taking a very different approach.

Chancellor Jeremy Hunt and Chancellor-turned-Prime Minister Rishi Sunak are instinctively, and politically, not fans of that kind of intervention. Although when it comes to specific cases, they may still be prepared to act.

Labour's plans are in contrast, inspired by what President Joe Biden has done in the US, to use billions of pounds of taxpayers' cash to stimulate green industries and create many thousands of green jobs.

As we get closer to the election the clash between the two main parties on this will only become clearer.

Upping the pace of protecting the planet is obviously not as straightforward as writing a Hollywood script, or making a speech. It requires huge amounts of cash from somewhere and a reckoning with the planning system - classic material for backbench bust-ups - and political will.

Acting decisively on climate change is a long-term game when politicians like the sugar-rush of quick wins.

Public budgets are tight. Personal budgets in a cost of living crisis more painful still. Yet there is a political and economic risk, as well as an environmental one, to governments that fall behind.

At 75, self-professed "boomer" Arnold Schwarzenegger says: "Sometimes I'm not with the programme when it comes to technology.

"Luckily, I have kids that kind of remind me all the time 'daddy, you're so old fashioned, come on, get out of it…' I have somebody that pushes me away from that old-fashioned way."

Politicians can't afford to fall out of fashion or voters may push them out of the way.