Private company

Audax

Logo: Audax Renovables, CC BY-SA 4.0, via Wikimedia Commons3

Spanish energy supplier

Audax Renovables, S.A., trading as Audax, is a Spanish electricity and natural gas company headquartered in Badalona, Catalonia. It supplies electricity and gas to end customers in several European countries and generates electricity from renewable sources using wind and solar photovoltaic technology.2 From Wikipedia, CC BY-SA 4.0

Last updated Oct 16, 2026.

Overview

2000Founded1

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Audax Renovables, S.A., trading as Audax, is a Spanish electricity and natural gas company headquartered in Badalona, Catalonia. It supplies electricity and gas to end customers in several European countries and generates electricity from renewable sources using wind and solar photovoltaic technology. Formerly known as Fersa Energías Renovables, it is listed on the Madrid Stock Exchange under the ticker ADX and has been a constituent of the IBEX Small Cap index since March 2020.2

How it started

Fersa Energías Renovables (2000–2016)

The company was founded in 2000 as Fersa Energías Renovables, a developer and operator of wind farms. It began trading on the Barcelona stock exchange in 2003 and joined the Spanish continuous market in 2007.

Takeover by Audax Energía (2016–2019)

In May 2016 the electricity and gas retailer Audax Energía, controlled by José Elías Navarro, launched a takeover bid for Fersa that valued the company at about €70 million. The bid was cleared by Spain's Comisión Nacional del Mercado de Valores in July 2016, and by August about 70.9% of Fersa's shares had been tendered; Francisco José Elías Navarro became chairman. Fersa was renamed Audax Renovables in 2017, and in 2018 Audax Energía was subsequently merged into the listed company.

International expansion (2013–2020)

The retail business expanded across Europe over the following years, entering Portugal in 2013, Italy in 2014 through the acquisition of the retailer Big Energia, Germany in 2015, and Poland in 2016 through the acquisition of Deltis Energia. In 2017 it acquired a 72% stake in the Dutch retailer Main Energie, and in 2020 it entered Hungary by acquiring the electricity retailer E.ON Energiakereskedelmi.

From Wikipedia’s article on Audax, shared under CC BY-SA 4.0.2

Timeline

  1. 2020Went public Listed on Madrid Stock Exchange1
  2. 2000Founded Founded1

Sources

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