Electricity Transmission Simulation
This interactive simulation traces the journey of electricity from a power station to a home, showing how the National Grid moves energy efficiently across long distances.
Electricity is generated at 25 kV and immediately stepped up by a transformer to 100–400 kV (user-controlled) for transmission across high-voltage overhead cables. The core physics principle is visible in real time: higher transmission voltage means lower current, which means far less energy lost as heat in the cables (P_loss = I²R). Drop the voltage slider and watch the cables glow red with wasted heat as efficiency collapses.
The energy passes through a grid substation (stepping down to 132 kV) and then a primary substation (stepping down to 230 V), before travelling along a service cable to the home. The house windows glow brighter as more power is delivered — dimming when generation is low or transmission losses are high.
What to explore:
- Raise voltage to 400 kV → near-maximum efficiency, cool cables
- Lower voltage to 100 kV → losses multiply 16×, cables heat up
- Reduce generator output → windows dim, homes powered count falls
Curriculum links: AQA Physics Topic 4 (electricity generation and the National Grid), transformer equation V₁/V₂ = N₁/N₂, power equation P = VI, efficiency = useful output ÷ total input.