Tamil Nadu is the eleventh largest state in India with an area of 130,058 km2 [50,216 sq mi] and the seventh most populous state with a population of 66,396,000. Electricity is a primary source of energy. Hence availability of electricity to all segments of society at reasonable price and at adequate level at all times is very important for development of the economy in the state. The demand for power is mainly due to population and economic growth, which reflects growth process – taking place in the primary, secondary, and tertiary sectors. Power development is one of the key inputs for the overall economic development of a state. Electricity is a special good and its generation and consumption have to be simultaneous, it cannot be economically stored. Another special feature of electricity is that its demand varies on hourly, daily, weekly, monthly and yearly basis. Its availability is one of the biggest inputs necessary for the sustained growth. This becomes even more important for a state like Tamil Nadu, which is one of the most industrialized and urbanised state in India. This paper mainly tries to analyse the various sources of electricity generation in Tamil Nadu.