Geoffrey Lean: Overnight, the US is going green – but we're stuck in a different age

Anyone who wants to see how the future is going to work should visit a patch of California once known as the Valley of Heart's Delight. For this strangely flat expanse at the southern end of San Francisco Bay that took its original name from the cherry and apricot orchards that once covered it has long started revolutions that have changed our lives.

Silicon Valley, as everyone now calls it, pioneered the developments that gave rise to the computer industry in the 1970s. In the 1980s, it led the biotechnology revolution. In the 1990s it famously drove the dot-com boom. And now it is taking on the biggest transformation of all by staking billions on making the future green.

I go there every year to judge some environmental awards. It has been amazing to see how much of the buzz and boundless self-confidence of the 1990s has come back as many of the stars of the IT revolution rush to make new fortunes in developing renewable energy. It looks as if the valley will become even more famous for the silicon solar cell than the silicon chip.

Some of the same buzz is beginning to seep into politics, as leaders begin to grasp that the future is beginning to arrive faster than any of us imagined. But while some politicians, like Barack Obama, have worked out how to ride the wave, others – like Gordon Brown – are floundering far behind.

Contrast, for example, the decision on Thursday to allow a third runway to be built at Heathrow with the forthcoming US administration's launch on the same day of a stimulus package largely based on green energy.

The Heathrow decision – personally rammed through a divided Cabinet by the Prime Minister – harks back to the politics and economics of the oil-soaked 20th century, when all expansion was good. The Obama package, instead, looks to the new age when climate change and the increasing scarcity of fossil fuels demand a new approach. Even worse for Mr Brown, David Cameron, on the very next day, declared for the new politics over the old by launching the most comprehensive set of policies for a low-carbon future ever drawn up by a major political party.

In Silicon Valley, there are few doubts as to where the future lies. "Remember the internet? Green tech is bigger," says John Doerr, the world's most influential venture capitalist. "This could be the biggest economic opportunity of the 21st century." Russell Hancock, chief executive of Joint Venture: Silicon Valley Network, an alliance of business, government, academia and local communities, adds: "Promoting the development of new technologies for alternative energy is the nation's best path to economic recovery."

The US package puts Mr Hancock's words into action. It is, as it says, "the first crucial step" in delivering the President-elect's campaign promise to create five million new jobs by investing $150bn (£100bn) in renewable energy. True to his word, Obama has now committed to doubling production from renewables in only three years, and to ensuring that they provide a quarter of US electricity by 2025. And he has pledged to improve the energy efficiency of two million American homes and three-quarters of government buildings, and to produce fuel-efficient cars.

"In the process," he says, "we will put Americans to work in new jobs that pay well and can't be outsourced – jobs building solar panels and wind turbines, constructing fuel-efficient cars and buildings, and developing the new energy technologies that will lead to even more jobs, more savings and a cleaner, safer planet in the bargain."

David Cameron is singing much the same song. His new policy document, "The Low Carbon Economy", says: "Decarbonising Britain will help create hundreds of thousands of jobs, raise skills and improve Britain's competitiveness." He plans to encourage families to install solar panels and other renewables by paying them for the energy they feed into the grid. He also wants to entitle each dwelling to a loan £6,500 – paid back through its fuel bills over up to 25 years – to improve their energy efficiency.

Significantly, both Obama and Cameron have prioritised one measure, promoted by Silicon Valley, which is an essential precondition of increasingly powering their countries by renewables: the creation of a "smart grid" which uses digital technology to allow two-way communication between electricity generators and customers. Amazingly, it can manage to make electrical appliances such as fridges or washing machines use power when it is abundant and cheap, and avoid peak times, when it would more expensive. This would smooth out the peaks and troughs of demand, allowing for the greater intermittency of renewable sources and make it much easier for families to make money by generating their own electricity.

But if Cameron resembles the quick-footed Obama, Gordon Brown is more like more like the lumbering John McCain. The defeated presidential candidate also promised to create millions of green jobs but produced no credible plan, vaguely citing old technologies like nuclear power. The Prime Minister, another fan of the atom, is planning his own green jobs consultation document. But a source close to the Energy Secretary, Ed Miliband, who is compiling it, yesterday admitted, with some hauteur, that no one had yet decided what to put in it.

The controversial decision to allow a third runway at Heathrow was presented, with similar hamfistedness, as a green measure. This takes something of a prize for cheek, since the runway would cause EU pollution limits to be breached, and do grave damage to Britain's attempts to combat climate change.

Encouragingly though, it proved too much for some of the newer ministers in the Cabinet to stomach. It provoked the biggest cabinet split of the Parliament, as the old and new politics clashed. Seven ministers, including Ed and David Miliband, Skills Secretary John Denham, Deputy Leader Harriet Harman and Environment Secretary Hilary Benn, mounted a sustained resistance. They won concessions, but sadly they were unable to prevail against the cabinet dinosaurs.

But the world is increasingly with them, and not with the prime minister and his die-hards. The United Nations Environment Programme's concept of a global Green New Deal, first reported in The Independent on Sunday in October, is gaining traction surprisingly fast – and not just with David Cameron who endorsed the concept last week, or Barack Obama who is implementing it.

In a little-reported initiative, oft-criticised China has launched a $142bn programme of environmental measures as part of its own stimulus package. And South Korea has announced no fewer than 36 separate "Green New Deals" to "ease people's pain and create jobs", by such measures as constructing bicycle tracks and highspeed railways and providing two million "green homes".

Of course, promises are one thing, action quite another. Al Gore, perhaps the greenest politician ever to hold high office, did little when in power. And New Labour came to power promising an integrated transport policy which never materialised.

The danger with Obama is that he will press ahead with expanding renewable energy without taking complementary measures to combat climate change. But he has provided some reassurance by appointing top climate scientists to his administration, led by Steven Chu, his energy secretary. By contrast, the Tories' most respected green shadow minister, Peter Ainsworth, has been tipped for the sack in the forthcoming Shadow Cabinet reshuffle, a move that would do much to undermine the Conservatives environmental credibility.

Back in Silicon Valley, optimism is undimmed. You can find respected figures who believe that producing solar power at much the same price as electricity from fossil fuels is "months not years" away. Electric cars are also approaching the breakthrough point. And Vinod Khosla, one of the dot-com giants, predicts that there will be six comparatively green second-generation biofuels competitive with petrol with four years.

They may be overoptimistic in their timings, but the trends are clear. The post-recession world will surely be very different from the one that preceded it. And it will be a world ready for a renewables revolution – not another carbon-belching runway at Heathrow.