Lesson 1 of 7

Why Power Markets Exist

7 min read

Every other track on this platform treats generation as something to be planned, dispatched or connected. This track asks a different question: who decides which power plant runs right now, and how much does everyone get paid for it? The answer, in most of the world today, is a market — and understanding why is the foundation for everything else in this track.

Why electricity isn't a normal commodity

Electricity has a property almost no other traded good has: at any instant, production and consumption across an entire interconnected grid must be equal, essentially exactly, or frequency starts to drift (as covered in the Grid Stability track). You can't warehouse electricity the way you'd store grain or oil waiting for a better price — at least not cheaply, at scale, historically. That single physical constraint is the reason electricity markets look so different from markets for almost anything else.

Two ways to answer the same question

Vertically integrated utility

A single company owns generation, transmission and distribution, and a regulator approves the prices it can charge. Which plant runs is a planning decision made inside that one company, not a market outcome.

Deregulated (liberalized) market

Generation is opened to competition among independent companies, coordinated by an independent system operator, while transmission and distribution typically remain regulated. Which plant runs is decided by competitive bidding, not a single company's internal plan.

Most of the world runs some blend of these two models. The United States, much of Europe, and a growing list of other countries have moved significant parts of their generation sector toward competitive markets since the 1990s; other regions still run largely vertically integrated systems. This track focuses mainly on how the market model works, since it's where most of the interesting economic mechanisms live.

The case for markets: efficiency through competition

The core argument for a market-based approach is simple: if many independent generators compete to sell power, and the cheapest ones are dispatched first, the total cost of meeting demand should be lower than if one company simply builds and runs whatever it decides to. This ordering — always calling on the cheapest available generation first — is called merit order dispatch, and it's the organizing principle behind almost every market mechanism covered later in this track.

Who actually participates

Generators

Power plant owners who bid to sell energy — from large conventional plants to wind and solar farms and battery operators.

System operator (ISO/TSO)

The independent, non-profit-motive entity that runs the market and operates the grid in real time — PJM, ERCOT and CAISO in the US, or a national TSO in much of Europe, are examples.

Retailers / load-serving entities

Companies that buy wholesale power and sell it on to households and businesses, often at a fixed retail rate that smooths out the underlying wholesale price volatility.

Large consumers

Industrial users and, increasingly, aggregated demand response providers who can participate directly in some markets rather than only buying at a fixed retail rate.