Electric power systems have traditionally been operated as natural monopolies. Restructuring has entailed un-bundling of hitherto vertically integrated organizations into independently managed generation, transmission and distribution systems. As a result, electric power markets can be divided into wholesale and retail layers.

The wholesale power market design proposed by the U.S. Federal Energy Regulatory Commission (FERC) in an April 2003 white paper FERC (2003) encompasses the following core features: central oversight by an independent system operator (ISO); a two-settlement system consisting of a day-ahead market supported by a parallel real-time market to ensure continual balancing of electric power supply and demand.

In this new environment electricity is traded like other commodities in ISO organized power pools. However, power systems must be in instantaneous power balance, i.e. demand must equal supply at all times. Moreover, at present, electric power cannot be stored economically in substantial amounts. The power flows on transmission systems are governed by physical laws of power flow such as the Kirchoff's law, and are constrained by the overall capacity of transmission lines. During the peak hours of electric power demand, the above mentioned constraints become binding affecting outcomes throughout the grid. Transmission constraints in particular create congestion, which can impede the generation and/or injection of electric power into the grid in "merit-order", i.e., from least-cost generator to high-cost generators. Electric power prices can be very volatile and hence, new forms of risk have arisen due to the restructuring.

As part of restructuring, congestion on electricity transmission grids is now handled in many energy regions by means of locational marginal pricing (LMP), i.e., the pricing of electric energy in accordance with the location of its injection or withdrawal from the grid. The LMP so calculated at a node k measures the least cost to supply an additional unit of load at that location from the resources of the system. The difference in LMPs at any two buses is known as congestion rent, which is collected by the ISO. In the case of grid congestion, LMPs can vary widely across the grid, which creates price risk for all market participants.

Using existing market design features, this thesis investigates the risk management issues of market participants and overall efficiency of the wholesale power markets. Additionally, I also study the market rules dealing with renewable energy sources.