There are two power exchanges in India - Indian Energy Exchange (IEX) and Power Exchange India Limited (PXIL), where electricity is being traded. The electricity prices are discovered on Day Ahead Market (DAM) of these power exchanges in every 15 minutes time block. These prices fluctuate in every time block, leading to fluctuations in a day, depending upon the electricity demand and supply position in the market at any given point in time.
The Government of India has enacted the Electricity Act, 2003 to consolidate the laws relating to generation, transmission, distribution, trading and use of electricity and generally for taking measures conducive to development of electricity industry and for protecting the interest of consumers.
The capacity of transmission lines depends on various factors like voltage level, conductor configuration, line length, inter-connection arrangement etc. As on 28 February 2018, a total of 3,87,383 ckm of transmission lines (220 kV and above) exists in India.