I would like nuclear fusion to become a practical power source. It would provide an inexhaustible supply of energy, without pollution or global warming.

The remark expresses a techno-optimist hope that a major scientific breakthrough—controlled nuclear fusion—could decouple human prosperity from the environmental costs of fossil fuels. By calling fusion “inexhaustible,” Hawking points to the abundance of fusion fuels (often framed as hydrogen isotopes) compared with finite coal, oil, and gas. His emphasis on “without pollution or global warming” situates fusion as a potential climate solution: energy-dense, low-carbon electricity that could reduce greenhouse-gas emissions and many conventional air pollutants. The quote also reflects a common scientific stance that long-term global challenges may require not only conservation and policy changes but also transformative energy technologies.