How Electricity Gets to Your House
Trace a single electron's worth of power from a spinning turbine to the outlet behind your couch, and understand every step.
This course is for members
$9 unlocks every course in the library, this one included, plus a credit to build a topic of your own and at least 10 new courses every month.
What you will learn about How Electricity Gets to Your House
The 7-day sprint
- Voltage, Current, and Power. Electricity is a flow of charge pushed by a voltage difference, and the power delivered is voltage multiplied by current.
- Where the Power Is Made. Almost all grid electricity comes from spinning a magnet inside coils of wire, and the only real difference between sources is what does the spinning.
- Transformers and Why Voltage Goes Up. Line losses grow with the square of the current, so raising voltage and lowering current is what makes long-distance transmission possible.
- The Transmission Grid and Substations. High-voltage lines form a meshed, interconnected network so that power can reach any load from many directions, and substations are the junctions where voltage steps down.
- Distribution and the Last Transformer. Distribution lines carry medium voltage down your street, and a local service transformer drops it to household voltage for a small number of homes.
- Inside the Panel. Your main panel splits incoming power into branch circuits, and breakers exist to protect the wires in your walls from overheating, not to protect your appliances.
- Balancing the Grid Second by Second. Generation must match consumption at every instant, and grid frequency is the signal that tells operators whether they are ahead or behind.
The 80/20: the 7 concepts that matter most
- Power equals voltage times current, and losses scale with current squared
- Transformers, and why the grid is AC
- Supply must equal demand every instant
- The voltage staircase from plant to plug
- Every circuit needs a return path, and ground is not the return path
- Breakers protect wires, not appliances
- You buy energy in kilowatt-hours, and when you use it matters
The core idea, explained like you are 5
Electricity is not stored in the wires and shipped like a package; it is a continuous loop that is generated and consumed at the same instant, and voltage is the pressure setting that makes the loop practical to run over hundreds of miles.
Then the quiz and the ladder
10 questions that correct you when you are wrong, and beginner, intermediate, advanced levels, each with a practical exercise.