While some intermittent small volume transactions did take place between utilities in the initial periods, it was only in July 2001 that the trading transactions began on a sustainable basis. And in that financial year itself, PTC traded 1617 Million Units (MUs) of electricity worth Rs. 364 Crores! PTC has thereon climbed a steep growth path, going on to trade more than 18200 MUs worth about Rs. 7845 Crores, during FY 2009-10.

PTC's demonstration of the concept as well as successful implementation of the same has prompted the inclusion of trading as a distinct licensed activity in the Electricity Act, 2003. It has also prompted many organizations, both public and private to enter the power sector especially in trading operations, bringing in competition and others drivers for efficiency in the sector in a very short time period. Short Term market comprises of bilateral transactions through trading licensees, between utilities, power exchange transactions and balancing market in the form of unscheduled interchange.

PTC is the most significant player in direct bilateral market and also in India's 1st national level power exchange, Indian Energy Exchange (IEX) which was co-promoted by the Company. The volume traded on IEX are about 10% of the total volume traded by PTC.

The contract duration vary from day-ahead to intra-day to up to 1 year. Medium term contract (up to 3 years duration) have also been allowed by the Central Electricity Regulatory Commission.

The short term trading of power is done by utilizing the spatial and temporal demand and supply mismatches for State Utilities and also by utilizing the generation capacity of Independent Power Producers working in merchant capacity. These transactions take place both on an inter-regional as well as on an intra-regional basis where the electricity is wheeled from one region to the other using the transmission lines of the Central Transmission Utility or is traded intra-regionally using both State as well as Central Transmission Utility lines.

PTC transactions are spread in all the five electricity regions of the country and almost all the State Electricity Boards / Utilities in the country are its clients. The quantum of energy (in Million Units of Electricity) traded by PTC since it has started trading on a sustainable basis, is as follows: