[1] Oil exploration began in the Parnaíba Basin at the end of the 1940s with two wells being drilled in Maranhão by the National Petroleum Council (CNP).

[2] In September 2009, OGX, the oil and natural gas branch of the EBX group, announced the purchase of a 70% stake in seven onshore blocks belonging to Petra Energia, which remained with 30%.

[5][6][7] In September 2011, OGX Maranhão acquired a 50% stake in the onshore exploration block PN-T-102 in the Parnaíba basin held by the companies Imetame Energia S.A., DELP Engenharia Mecânica Ltda.

[1][13][14] The largest natural gas producing states in 2021 were: Rio de Janeiro (64%); São Paulo (12.4%); Amazonas (10.15%); Maranhão (4.38%); Espírito Santo (4.09%); Bahia (4.06%); Ceará/Rio Grande do Norte (0.50%); Sergipe/Alagoas (0.45%).

The cities involved in gas exploration are: Lima Campos, Santo Antônio dos Lopes, Capinzal do Norte, Trizidela do Vale and Pedreiras.

[16][17][18] In August 2011, the Maranhão III TPP project won the A-3 auction held by the Brazilian Electricity Regulatory Agency (ANEEL).

[19][20] On January 19, 2013, Parnaíba I began supplying energy to the National Interconnected System (SIN) on a test basis through the operation of the first turbine; it received commercial authorization on February 1, 2013.

[36][37] The complex is divided into: The reservoir-to-wire (R2W) model consists of thermal generation in the vicinity of onshore natural gas producing fields.