Extremely severe extinction events happen every 100M years or so and just switching to sustainable energy will not be enough to stop them. Space satellites to control temperature and massive geo-engineering will be needed or it will be game over.

Elon Musk stated that extreme extinction events occur roughly every 100 million years, and simply transitioning to sustainable energy will not prevent them. He believes that controlling global temperature with space satellites and implementing massive geo-engineering projects will be necessary to avoid catastrophic outcomes.