Balancing Act

Supply must equal demand

An interactive lesson with 6 steps, about 5 minutes: you predict, drag and solve, with instant feedback on every answer. It runs in your browser and needs JavaScript.

What you’ll learn

• Supply and demand must balance every second.
• Grid frequency dips when demand exceeds supply.
• Storage like pumped hydro and batteries smooths out mismatches.

Steps

1. No storage in the wires
2. Half-time kettles
3. The duck curve
4. A mountain battery
5. A tonne for a kilowatt-hour
6. Storing energy