Use the simulation in your science or Physics class to illustrate energy efficiency
This simulation helps GCSE Physics students compare the energy efficiency of four common light bulb types — Incandescent, Halogen, CFL, and LED — using accurate, curriculum-aligned efficiency values.
For each bulb, 100 J of electrical energy enters the device and splits into two output streams: useful light and wasted heat. The Sankey-style bands are drawn proportionally to the energy values, so students can immediately see the difference in scale between a good and poor converter of energy. Animated particles flow through the device and branch into the correct streams, reinforcing the idea that energy is always transferred — never created or destroyed.
The four efficiency values used are the GCSE standard figures:
- Incandescent — 10% efficient (90 J wasted as heat)
- Halogen — 20% efficient (80 J wasted as heat)
- CFL — 70% efficient (30 J wasted as heat)
- LED — 90% efficient (only 10 J wasted as heat)
The stat cards beneath show useful output, wasted energy, and efficiency percentage for the selected bulb, updating instantly when a new bulb is selected.
This supports the following GCSE Physics specification points across AQA, OCR, and Edexcel:
- Efficiency = useful output energy ÷ total input energy (× 100%)
- Energy is dissipated to the surroundings in every device — no device is 100% efficient
- Sankey diagrams represent the proportions of useful and wasted energy transfers
- Students should be able to compare the efficiency of different devices and explain why some waste more energy than others
- Reducing energy waste improves efficiency and lowers energy consumption