3.8 Conclusion: Energy Supply and Demand

Lesson 3 Review

Throughout this lesson, we've traced humanity's energy journey: from biomass-dependent societies before 1800, through the fossil-fueled explosion of the Industrial Revolution, to today's complex global system where over 80% of energy still comes from oil, coal, and natural gas. We've seen how energy use per person varies dramatically by country—and how factors like efficiency, climate, economic structure, and policy shape those differences far more than income alone.

Most importantly, we've looked ahead. The International Energy Agency presents us with three distinct pathways:

• Current Policies: ~3°C warming by 2100
• Stated Policies: ~2.5°C warming if promises are kept
• Net Zero by 2050: Limiting warming to ~1.65°C through rapid clean energy transition

The data is clear: global energy demand will continue to rise, especially in developing economies. But how we meet that demand is the defining question of our century. Renewable energy and electrification are accelerating. Nuclear power is being reconsidered. Efficiency gains offer immediate impact. And every nation—and every individual—has a role to play.

Your takeaway: Understanding energy isn't just about memorizing statistics. It's about recognizing connections—between history and innovation, between policy and personal choice, between today's consumption and tomorrow's climate. As you move forward, keep asking: What kind of energy future do we want to create—and what will it take to get there?