It's always exciting to be in California, particularly when venture capitalists are working themselves into a frenzy about an innovation such as the Bloom Box—a low-carbon fuel cell system now hailed as the most radical technology to have come out of Silicon Valley since the PC. 

Only time will tell whether Bloom Energy will fulfil the dreams of backers such as the legendary John Doerr of venture capitalists Kleiner Perkins Caufield & Byers. But the initial signs are promising: among customers already signed up are Coca-Cola, eBay, FedEx, Google and Wal-Mart.  And at the heart of the Bloom Box system, the current version of which weighs 10 tonnes and costs around $800,000 (£537,000), is something that could help drive the low-carbon economy.

Travelling around the Golden State earlier this year, I dropped in on the Cleantech Forum. After trekking through the "valley of death", as Cleantech Group president Sheeraz Haji put it, it was apparent that many cleantech firms saw operating conditions improving—partly because of the $512bn commitment in government stimulus funding. But Haji warned that China's $200bn stimulus is already having decisive effects, with China and Hong Kong accounting for 69 per cent of cleantech investment last year.

I was in California to help guide the founders, chief executives and senior executives of 19 UK cleantech companies taking part in the first Clean & Cool Mission. And it was striking how the sustainability issue emerged everywhere, whether to giant companies such as Hewlett-Packard, San Francisco's City Hall, leading change agents such as Arup or IDEO, or start-ups such as Better Place or Serious Materials.

Cleantech Group executive chairman Nick Parker told the forum's opening session that "creative destruction is accelerating". Who, he wondered, would be tomorrow's "clean chips"?

One example could be Veolia Environnement, which trumpeted its new Innovation Accelerator, an initiative that boosts start-up development. It expects to be joined on the forum platform next year by the bosses of at least four new cleantech firms it hopes to be working with by then.

John Elkington is co-founder of SustainAbility and Volans (www.volans.com)