📗 Oil, Gas, Hydroelectricity, Nuclear power and Coal are the five constituents of conventionally used primary energy. Wind and solar are two examples of non-conventional sources. The Indian oil and gas sector constitutes 38% of total conventional primary energy consumption, which is lower than the world average of 62%, the per capita consumption of oil and gas is 117 kg against the world average of 925 kg's. The public sector undertakings in the oil and gas sector account for over 38% of total profit after tax earned and 45% dividend declared by PSU s as a whole. The share of petroleum sector in national excise and custom duty collections is at 20%. Public enterprises (especially oil sector companies) which constituted an important segment of the economy, which been has assigned a place of prime importance in the planned economic development of India, were expected to play a new role in the era of liberalization, privatization globalization which was welcomed true heartedly by the Indian economy.