Petrobras' most important assets are petroleum reserves in Brazil. Its oil field in the Campos Basin accounts more than 80% of the Brazilian oil production. The company also works on developing the "green energy", including biodiesel fuel. Petrobras recently opened its business to the ethanol fuel, facing great competition against the North American ethanol. However, investment in biofuels will represent only 1% of the company's profit between 2008 and 2012.
Petrobras is involved in the following areas of business:
- Domestic sales: Domestic sales represent the majority of the company's profit and includes the extraction and distribution of oil, natural gas, electricity and petrochemical products;
- Export: The main exports are not of oil extraction itself, but are related to mechanic technologies. However, it is planned to the company exports oil in large quantities when it begins to explore the Jupiter and the Tupi fields (see "List of recent oil field discoveries");
- Foreign exchange gains: The company imports natural gas from other South American countries, mostly from Bolivia. According to the Brazilian group National Petroleum Agency, Petrobras owns Brazil's largest and most important gas pipe network, having a near monopoly of the natural gas marketed in the country.
Petrobras works extensively with foreign acquisitions too, buying and controlling the most important energy companies in South America and exploring huge deep-water fields of West Africa and the Gulf of Mexico. Petrobras is known for its technology in deep-water exploration. The Tupi field, which could be the world's third largest oil field (although data is still unverified), is a deep-water discovery, located in the pre-salt layer.
The company began to increase profits from 2002, with the government's heavy investments. In the first quarter of 2008, Petrobras reached the market value of US$295.6 billion, surpassing Microsoft (US$274 billion) and becoming America's third largest company, ahead of giant oil companies such as BP and Chevron-Texaco, and only behind of ExxonMobil and General Electric. Petrobras' market value is also bigger than Industrial and Commercial Bank of China (US$289.3 billion), making it the sixth biggest company by market value in the world.
Comparison with world-wide companies
| Company | Reserves (MM boe) | Current Years of Production | Oil & Gas Production (1000s boe/d) 2006 | Oil & Gas Production Growth (%) 2006 |
| Petrobras | 11,458 | 14.2 | 2,287 | 4.5 |
| BP | 17,368 | 10.4 | 3,926 | -1.9 |
| ChevronTexaco | 11,020 | 10.9 | 2,667 | 6.1 |
| ExxonMobil | 21,518 | 11.3 | 4,238 | 3.8 |
| Royal Dutch Shell | 11,108 | 6.7 | 3,474 | -1.0 |
Growth
- Rising prices: the company profited from rising oil prices in 2007-2008.
- Increasing demand: oil demand has increased drastically in the emergent countries, for which Petrobras exports its technologies. The BRIC countries' (Brazil itself, Russia, India and China) growth explains this huge demand. The Brazilian self-sufficiency in Petroleum (as of May 2006) allowed the company to export small quantities of oil.
- Political issues: despite of being nearly half privately owned, the majority of shares belong to the Brazilian government, which gives it control of the company's finances and operations. The recent growth of the company is explained by political stability. Since 1997 the Brazilian oil market was opened to foreign investments, but Petrobras continues to be the largest oil company in the country, enjoying a near monopoly.