They are seen as a great clean energy hope for future sustainable power generation.

And on the larger scale, too, the technology is making progress - to drive cars and buses, and to power buildings not connected to a national grid.

'Dramatic changes'

As the cost of production falls and efficiency increases, fuel cells are expected to find many more applications.

Sir David predicted some "dramatic changes" in the emerging industry over the next 10 to 20 years.

But, he said, government bodies, industry, academia and other interests had to work much closer together in order to push the technology into the mass market.

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Delegates at the Ninth Grove Fuel Cell Symposium in London were told that consumer electronics offered an obvious route forward.

"Consumer electronics will represent the first major mass market for fuel cells," said George Apanel from SRI Consulting, a chemical industry consultancy.

"It is the beginning of the personal power revolution where people will be able to divorce themselves from the tyranny of the grid."

He predicted the widespread availability of methanol fuel cells for portable consumer electronics within two years.

With 470 million consumer electronic devices requiring portable power, it could represent a fuel cell business worth about $25 billion, he added.

He received the Grove Gold Medal at the symposium for his life's work on clean energy.

The refinement of fuel-cell technology was one of the most immediate challenges facing humans in the coming years, he said.

California currently had six hydrogen fuel-cell buses running, but that was nowhere near enough, he argued.

The state has recently agreed plans for a Californian Hydrogen Highway, which aims to create 50 to 100 hydrogen refuelling stations, servicing 2,000 hydrogen-powered vehicles by 2010.

"Despite the fact that fuel cells are not in widespread use, we have the knowledge and the products to make it a real prospect," said Dr Lloyd.

He urged the introduction of new legislation to drive the whole field forward, and called on governments to make environmental protection a core policy concern.

"Fuel cells are the key technology of the future; we have the power to make it happen," he said.

Regulation push

Now that the automobile industry is growing increasingly concerned about fuel certainty, it is starting to look much more seriously at fuel cells.

Late last year, Honda released its third-generation fuel-cell car design, the Honda FC Stack FCX.

But a PricewaterhouseCoopers Fuel Cell Industry Survey this week also revealed that many in the industry were continuing to see poor returns, despite pumping millions into research and development.

This is blamed on delays in the take-up of fuel-cell technologies. Toshiba, for example, has developed a fuel-cell laptop, digital music player, and a mobile phone - but regulations are a barrier to their introduction.

Until the regulations change - they will be reviewed in 2007 - Toshiba cannot launch the products on to the market.

One of the big drivers behind fuel cells is obviously their cleaner emissions. But another concern, beyond climate change, is ensuring the security of energy supplies.

The UK's oil and gas reserves in the North Sea are finite, and it is increasingly looking to import energy.

"If we can move towards more indigenous sources of energy, then we are moving away from insecurities associated with imports," said Sir David.

In the UK, the fuel sector is relatively strong, he added, with more than 100 companies and 35 academic or contract groups working in the area.

Globally, companies such as BP, BOC, Rolls Royce, and Honda are all very active in pushing fuel cell technology.