Wholesale electricity generation market shares by company in 2018 (GB)

Chart

Source: Ofgem calculations using data from Elexon and NETA reports.

Information correct as of: April 2019

This chart shows the market shares of companies who supply electricity to the GB National Transmission System by year. 

The companies with the largest 8 market shares are identified largest to smallest, with all other companies shown as ‘Other’.

Policy Areas:

  • Electricity - wholesale markets

Data Table

Wholesale electricity generation market shares by company in 2018 (GB)
CompanyShare
EDF27%
RWE13%
SSE9%
Drax7%
Uniper6%
EEX5%
ScottishPower3%
Orsted3%
Other28%

More information

Wholesale electricity supply market shares: At-a-glance summary

This chart shows the market shares of companies who supply electricity to the GB National Transmission System by year. 

The companies with the largest 8 market shares are identified largest to smallest, with all other companies shown as ‘Other’.

Our analysis of market concentration suggests that the GB wholesale electricity market appears to have relatively low levels of concentration. 

In 2018, EDF Energy had the largest share, accounting for over a quarter of total generation. However, EDF Energy’s generation portfolio is mostly nuclear plant. Nuclear plants have very low marginal costs and are not designed to frequently increase or decrease output. This means they generally run as a flat baseload source of power at high-load factors.

Relevance and further information

Market shares are an important indicator of trends in market concentration and competition. High market shares for a small number of firms suggest low levels of competition, and vice versa.  

Methodology

We calculate market shares from metered volumes associated with individual power stations and interconnectors (called Balancing Mechanism Units or BM units). 

Volumes are split based on equity stakes.

Date correct
April 2019
Policy area