Blog: For a future bigger than Google, just solve RE<C

Editor's note: CNN's Hugh Riminton will be writing a daily blog on the issues throughout the week of Going Green: Search for Solutions.

HONG KONG, China (CNN) -- Google shares have dropped two hundred bucks since they peaked at $724.80 last November.

The stock is hardly alone in heading south but the damage is not limited to Google shareholders.

A couple of years ago, the Google empire was extended to Google.org. Cashed up with an endowment of three million Google shares, its mission was to make "strategic grants and investments."

The share price fall has trimmed $600m off that potential kitty but Google.org executive director Larry Brilliant still has $1.5 billion or so to play with. And much of the money is going on renewable energy research.

It makes him a powerful player.

By comparison, the budget of the U.S. government's National Renewable Energy Laboratory, which claims to be the "primary laboratory" for this kind of work, has averaged less than $300m a year since 2002.

When it comes to clean energy research, says Brilliant, "you realize how little (money) has brought us so far and how much more money can bring us so much further."

The aim is summed up in this: RE<C.

It is not mathematics. Simply geek-speak. The goal is to find renewable energy sources, wind, wave, geothermal, solar -- anything anyone can think of -- that can provide utility-scale power more cheaply than coal.

Utility-scale? As Brilliant defines it, one gigawatt or more -- enough to power San Francisco. Boutique is fine but the world can't afford to muck around any more.

It must be cheaper than coal, says Brilliant, because anything more expensive than coal won't wean people off coal. And the technology must be profitable because if it's not, "nothing is sustainable."

They haven't cracked it yet but all of this is symptomatic of another deep global shift sparked by climate change. Green was hippie. Now it's a gold rush.

To reframe the formula: RE<C=$$$.

Ron Pernick and Clint Wilder, authors of "The Clean-Tech Revolution," state what is becoming increasingly obvious. "Trillions of dollars" await whoever comes up with a way out of our dirty energy dilemma.

Dr Brilliant himself was a Bay area hippie in the 1960s. He spent years living in an ashram in India before helping to eradicate smallpox. He might be part of Google these days but he believes the search giant will be dwarfed by what's coming next.

"The revolution we saw in Silicon Valley," he told me, "is nothing compared to the economic and cultural potential of renewable energy."

Google's investment may be a way of future-proofing its own business. General Motors, once a titan of global industry -- and still claiming to be the world's biggest automaker -- is now said to be within sight of bankruptcy. Its stock price this week sank below ten dollars -- lower than in half a century.

Everywhere the same message: Move or die.

So my question is: Which one will it be? What's the technology that's going to meet our energy needs without cooking the planet?

As ever, have your say in the 'Sound Off' box below.

And thanks for all your replies this week. I've learnt from them. And that's been fun.

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