Transmission vs. distribution
The highways and the side streets of the power system.
Getting electricity from a power plant to your outlet happens in two stages. Transmission is the highway system: very high-voltage lines (often hundreds of kilovolts) that carry bulk power over long distances with minimal loss, using the big steel towers marching across the landscape. Distribution is the local network: substations step the voltage down, and lower-voltage lines on wooden poles or underground carry it the last few miles to homes and businesses.
The split matters for cost and reliability. Most outages happen on the distribution system when a storm takes down a local line, while transmission failures are rarer but far bigger when they occur. And as demand grows and clean power gets built far from cities, the bottleneck is increasingly transmission: the queue of projects waiting for new long-distance lines is one of the energy transition's hardest constraints.
Frequently asked questions
What's the difference between transmission and distribution?
Transmission is high-voltage, long-distance bulk power (the big towers). Distribution is the lower-voltage local network that delivers power the last few miles to your home.
Which causes more outages?
Distribution. Most blackouts are local lines knocked out by weather. Transmission failures are rarer but affect far more people at once.