INTERNET STOCKS are surging again. And biotechnology still has great promise. But I’m betting that the next Bill Gates, whoever he or she is, will be an environmental entrepreneur. Why? Because despite the recent focus on the potential costs to society of climate change, solving this challenge may also present the greatest economic opportunity of our time.

The British government report on the economics of climate change by the former World Bank chief economist Sir Nicholas Stern, for example, indicates that the market for low-carbon technologies could generate $500 billion (£265 billion) by 2050.

But that may be conservative. The energy and transport sectors alone now represent almost 15% of the $43,000 billion global economy. If low-carbon, energy-efficient technologies grow to just 10% of this over the next 45 years, that’s a $645 billion market.

And that does not include any environmentally beneficial innovations in manufacturing, consumer goods and services, or many other industries.

Society seems to be approaching a tipping point in its attitude to the environment and, at times like these, new markets are born. Innovation and productivity are unleashed. That’s why some are thinking the drive towards greater resource and energy efficiency will rival the internet boom.

There is already a sharp increase in entrepreneurial and investor activity. In America, investment in the emerging “cleantech” sector has grown from less than 2% of all venture-capital investments in 1999 to more than 13% today, making it the third-largest investment category.

In Europe, more than $2.3 billion has been invested in clean technologies in the past three-and-a-half years alone. Much of this is going into a broad variety of green power technologies, from thin-film solar panels that can be applied direct to windows, to micro-wind turbines that can be mounted just about anywhere, to biofuels that are derived from agricultural waste.

While some green technologies have yet to reach a scale or cost that enables them to compete with conventional alternatives, being green is no longer simply about being responsible or having to sacrifice. In developed economies, the new green is as much about style, performance and comfort as it is efficiency.

Toyota’s sleek hybrid, the Prius, has proved that. And it has set in motion a competitive dynamic that is already changing the entire motor industry.

In developing economies, green technologies are helping countries to raise their standard of living more quickly, cheaply and cleanly, leapfrogging the old western model of development.

Last year, for example, one of the fastest-growing markets for residential solar applications was in . . . Kenya, where many families who are not on the local grid are using low-cost, low-quality photovoltaic cells to charge a car battery that can power a light, a radio, or perhaps a television for a few hours in the evening.

Some sceptics argue that continued growth in the market for low-carbon, energy-efficient technologies will depend on continued high prices for both oil and carbon. The price of oil and carbon will be key drivers of how fast these technologies are adopted, it’s true. But I am not sure they are as important as some make them out to be. If the early signs of climate change continue to grow, the market will simply demand its own solutions.

So who will be the next Bill Gates? Perhaps it will be the entrepreneur who unlocks the potential of hydrogen. Maybe it will be someone who figures out how to improve greatly our ability to harvest sunlight, or the person who invents a way to suck carbon straight out of the atmosphere.

Perhaps we will even see a merging of the digital revolution with the energy revolution. Vinod Khosla, the founding chief executive of

Sun Microsystems and one of the world’s leading venture capitalists, who has lately focused on biofuels, has said: “Many new Googles and Yahoos and Ebays will be created in this new industry.”

Will addressing climate change and energy scarcity cost us something? Of course. There will be winners and losers and significant economic disruption. But for those who seize the opportunity successfully, green will be the new gold.

Bill Gates became the richest man on earth by helping billions of people to participate in the information age right from their desktop. But I predict that the next Gates will rise through knowledge of green power.

Could it be you?