Madison Gas & Electric

The major transmission networks in North America are currently divided into ten ISOs which run the wholesale electricity markets across the country. The Midwest Independent System Operator (MISO) is the designated ISO for the Midwest United States and Maintoba, Canada, which began market operation in 2005. In 2011, the value of the real time load cleared was $18 billion. This money is dispersed to generating assets, transmission improvements, wind integration, long term planning, and to run MISO. The pricing scenarios used in this paper will be taken from MISO’s market data. MISO’s mission is to ensure reliable, least-cost delivered electricity for consumers.


Here are the wholesale prices for utilitiy Madison Gas and Electric. The prices on the grid are decided by an independent entity know as Midwest Independent Systems Operators (MISO). They clear the market for bulk electricity in two stages, a day-ahead market and a real-time market. The real-time market is on a rolling 5 minute basis, so every 5 minutes they have to clear a market which involves finance calculations and more differently power flow equations. The day-ahead market is difficult as well and is more about strategic decisions for the future uncertain demand.

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Rolling Averages:

Daily Weekly Monthly Yearly

Interesting Features

Graph Explanation

This graph displays the time-series prices for the day-ahead and real-time prices for Madison Gas & Electric. These are the prices determined by an optimization routine done by the Midwest Independent System Operator (MISO) in order to determine a least cost supply of power to meet demand and maintain given reliability standards. The day-ahead prices are determined, you got it, a day in advance. The generators submit there bid offers and the demand is estimated using a forecasting procedure. The day-ahead problem has two complicating elements and determines hourly prices for the following day. First, MISO needs to determine which generators to have online throughout the next day. Second, they need to ensure they are N-1 secure in order to meet requirements set by the Federal Energy Regulatory Commision (FERC). N-1 secure means that the power grid is capable of withstanding any one power line or generator going down and not disrupting load. They must also be able to move to an operating point in which no lines are overloaded within a given time frame. Since the day-ahead problem is scheduled to forecast, the real-time problem must make up for errors in forecast as well as unforeseen events such as a power line or generator outage. This is done on a 5 minute basis, that is, every 5 minutes the new supply offers are cleared with the realized real-time demand.

Each day is represented by its average price for both the real-time and day-ahead prices. The region between the maximum price and the minimum price for any day is shaded to represent the prices it took on any given day.


LMP is Locational Marginal Price
MCC is Cost of Congestion component of LMP
MLC is Loss component of LMP

Show Series:

Rolling Averages:

Daily Weekly Monthly Yearly


[1] MGE's Generation Assets

Here is MGE's current electricity production portfolio from the source themselves.

Power Systems

Formulations, Calculations, and Vizualizations