Meet the companies tackling nine of humanity's biggest problems -- and making millions saving us from ourselves.
Problem #1: Global Warming
Problem #1: Global Warming
The background: Carbon dioxide makes up nearly 80 percent of all greenhouse gases. More than a quarter of that CO2 comes from electrical power plants.

The solution: Wind power, thanks to recent breakthroughs in turbine and transmission technology; it's also 70 percent cheaper than solar power. In May, Dublin-based Airtricity, the world's fastest-growing wind developer, announced plans for a European supergrid - a network of 2,000 offshore wind turbines in the North Atlantic. The grid would initially supply 10,000 megawatts to 8 million homes.

The payoff: Founded just seven years ago, Airtricity is on track to bring in $657 million in revenue by 2010. The company operates 16 wind farms in the United States, the United Kingdom, and Ireland.

The opportunity: Airtricity is already lobbying for government approvals. But there's opportunity for other wind producers to start banding together, since scale is what's needed most to lift wind out of the "alternative" market.

Global Warming

Oil Dependency

Hunger and Malnutrition

Dirty Air

Dirty Water



Drug-Resistant Infections

Waste Disposal
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