Sustainable Energy
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Bright ideas that could change the lives of billions

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As the number of people on our planet increases at a rapid rate the need for clean and reliable sources of energy is set to become pressing. The United Nations currently estimates the global population will reach 9.7 billion by 2050.

Ahead of CNBC's Sustainable Energy Brainstorm event taking place on July 9 in Paris, we take a look back at some of the clean energy technologies and ideas that Sustainable Energy has previously featured. These innovations are aimed at helping transform the lives of people around the world and securing their energy future.

saptarshi mandal photography | Moment | Getty Images