Lesson 4 of 8

European Electricity Markets

The previous lessons used the vocabulary of US markets, where much of the theory was first put into practice. Europe solves the same problems with a different architecture: zonal prices instead of nodal ones, power exchanges and TSOs with separate jobs, and a chain of markets coupled across more than twenty countries. If you study or work in Europe, this is the market your grid actually runs on.

The building blocks

Bidding zone

The largest area within which electricity can be traded without allocating transmission capacity — one price per zone and market time unit. Most zones are national; Germany and Luxembourg share one, while Italy, Norway, Sweden and Denmark are split into several.

NEMOs (power exchanges)

Nominated Electricity Market Operators such as EPEX SPOT and Nord Pool run the day-ahead and intraday markets and operate the coupling algorithms together.

TSOs

Transmission system operators calculate how much cross-zonal capacity the market may use, run balancing and redispatch, and settle imbalances.

Balance responsible parties

Every supplier, generator and trader belongs to one. They submit schedules and pay for any deviation; in Germany this is the Bilanzkreis system.

Regulators

National regulators (in Germany the Bundesnetzagentur) supervise their markets, and ACER coordinates them at EU level.

From years ahead to real time

Forward and futures

Years to days ahead, on exchanges such as EEX or bilaterally — mainly for hedging. Long-term cross-border transmission rights are auctioned separately.

Day-ahead (SDAC)

At 12:00 CET the coupled day-ahead market clears every bidding zone for the next day in one optimisation (the Euphemia algorithm), allocating cross-zonal capacity together with energy. Since 1 October 2025 it uses 15-minute products.

Intraday (SIDC)

Continuous cross-border trading lets participants correct their positions as forecasts improve, complemented since 2024 by pan-European intraday auctions.

Balancing

The TSOs cover the remaining imbalance with FCR, aFRR and mFRR, increasingly activated through the shared European platforms PICASSO and MARI.

Imbalance settlement

Afterwards, each balance responsible party pays or receives the imbalance price for its deviation in every 15-minute settlement period — the incentive that keeps schedules honest.

Market coupling

Before coupling, traders had to buy cross-border transmission capacity separately from the energy it would carry, and often got it wrong — power flowed from high-price to low-price countries. Implicit allocation fixes that: the day-ahead algorithm assigns cross-zonal capacity automatically to the trades that create the most value. When a border is not congested, prices on both sides converge; when it is, they separate and the price difference becomes congestion income for the TSOs.

How much capacity the market may use is calculated in two ways. The simpler net transfer capacity method gives each border a fixed limit. Flow-based market coupling, used in the Core region of central Europe since 2022, models how each trade actually loads the critical lines of the meshed grid. EU law also requires TSOs to offer at least 70% of the capacity of critical network elements to cross-zonal trade, so that internal congestion is not simply pushed to the borders.

What zonal pricing leaves out: redispatch

Inside a bidding zone, the market assumes unlimited transmission. When the resulting schedule would overload a line — typically when wind power in northern Germany has to reach demand in the south — the TSOs correct it after the market has cleared. They pay generators before the bottleneck to reduce output and generators behind it to increase it, and since 2021 also draw on renewable and smaller plants (Redispatch 2.0). The cost, several billion euros a year in Germany, is recovered through network charges rather than shown in the wholesale price. Whether the German–Luxembourg zone should be split is under formal review under EU law and remains politically contested.

Nodal and zonal side by side

Price resolution

Nodal (PJM, ERCOT, CAISO): a price at every node. Zonal (EU): one price per bidding zone.

Dispatch

Nodal: the ISO commits and dispatches individual units centrally. Zonal: participants self-schedule the portfolios they sold.

Congestion

Nodal: all congestion is priced in the market. Zonal: congestion between zones is priced; congestion within a zone is handled by redispatch outside the market.

Hedging

Nodal: financial transmission rights between nodes. Zonal: forward contracts per zone plus long-term cross-border transmission rights.