The French government netted 1.14 billion euros with the sale of 100 million Engie sales, 10 million more than originally offered, the APE agency which manages public shareholdings announced in a statement late on Tuesday.
The sale leaves the state with 28.7 percent of Engie's capital and 32.6 percent of the voting rights.
The company, which used to be known as GDF Suez, is the world's top independent electricity producer and a leading liquefied natural gas importer.
The European Commission on Tuesday agreed that the government could pump 4.5 billion euros into Areva, which lost 10 billion euros between 2011 and 2015 and has seven billion euros of debt.
It is under pressure to pay back a bank loan very soon.
A consortium comprising Mitsubishi Heavy Industries and Japan Nuclear Fuel Limited has already offered to invest 500 million euros in Areva, which is to be broken up into two companies.
As of last April, the French state held stakes in 81 companies, including telecommunications operator Orange and aircraft engine maker Safran, with a portfolio estimated to be worth 90 billion euros.
The value of the listed companies fell by 11.5 percent last year to 59.7 billion euros, mostly due to the sliding value of shares in the energy companies EDF, Areva and Engie.
EDF opens wind and solar farms in US
The government is also committed to investing three billion euros of a planned four billion euros capital injection in EDF this year.
The power company, which aims to double its renewable energies capacity by 2030, on Wednesday announced that four wind and solar farms were up and running in the US.
EDF Energie Nouvelles said in a statement that four wind farms had started production in the US in December and January at Tyler Bluff and Salt Fork in Texas, Great Western in Oklahoma and Kelly Creek in Illinois.
Most of Tyler Bluff's electricity will go to Procter and Gamble, which intends to power all its household hygiene and products factories with renewable energy, while Great Western will provide electricity for a Google data centre.