NOTE the Frequently Asked Questions section below

Some specific points on Transmission Atlas^™ products and PowerWorld Simulator

• In addition to their extraordinary analytic firepower, Transmission Atlas™ products and PowerWorld Simulator offer a unique animated graphic interface with detail presentation and contour mapping capabilities that make illustration and presentation of power flow to non-engineers and decision makers both easy and effective. A thorough analysis of this capability is available in the December 2002 issue of "Electric Power and Light".
• Developed using modern object-oriented programming languages, PowerWorld Simulator and Transmission Atlas are much more flexible and responsive than older FORTRAN based Programs. Accordingly, customization and product upgrades are less expensive over time.
• PowerWorld/Transmission Atlas continue to add new features, and as this range of capabilities grows, PowerWorld/Transmission Atlas is on the way to becoming one of the most versatile Power Analysis Platforms.
• While initial sales were seen in the Eastern Interconnect and ERCOT, PowerWorld Simulator and Transmission Atlas is making inroads within the Western Interconnect, including extensive work with the Bonneville Power Administration (where it is used for management, analysis and planning) and the California Energy Commission specifically in the area of Strategic Renewable Energy Analysis.
• Successive generations of PowerWorld Simulator have been developed as the result of feedback from strategic customers within the power regions and reflects the challenges that specific region members as well as transmission managers and power traders, across the country, are facing and will face in the future.
• While PowerWorld Simulator can integrate and inform (both read and write) power flow cases built by or used by its competitors, the reverse is not often the case. Accordingly, PowerWorld and Transmission Atlas fit seamlessly with existing legacy software, both in house or when working with strategic partners.
• Transmission Atlas continues to add information and detail to its power flow structure, in direct response to customer request, most recently in the areas of generation and congestion analysis. In addition, Transmission Atlas has been adding new ISO configurations as they are developed.

Frequently Asked Questions:

What is the Transmission Atlas?
The Transmission Atlas is a map product meant for use with PowerWorld Simulator or Viewer. It began with Transmission Atlas 2001 based upon the cases found in the annual Federal Energy Regulatory Commission (FERC) 715 filings and has been expanded substantially as we continue to improve and add to the Transmission Atlas. It still includes both substation and bus maps. However now we have the entire Eastern Interconnect combined into a single oneline map of North America. We also have onelines for the ERCOT and WECC regions. The onelines are also now have everything in the power flow cases mapped down to the lowes kV level.

We now have Transmission Atlas-PJM Monthly Network Model which is a bus oneline based on the PJM Monthly Network Model cases available to members of PJM.  This case is particularly useful in LMP analysis as it has a cross-reference to the PJM prices published by PJM. Also available is Transmission Atlas-CAISO - CAISO CRR FNM cases for power markets.

Where do you get the information used to build the diagrams?
The Transmission Atlas data is based on the case data that is already available in the FERC 715 filings and location data approximated from maps. While geographical accuracy is important, the purpose of the maps is to visualize the underlying power-flow data and electrical connectivity. In some instances, the substations or buses are placed on the diagram based on geographical proximity gleaned from sources without exact latitude or longitude information. As we move forward with new versions, Energy Visuals is enhancing the product with more applicable power flow case data.

Can I use the Transmission Atlas for consulting projects?
Yes. The diagrams can be used for power-flow visualization and presentation. The underlying power-flow cases can be used for power system analysis.

Can I add to the diagrams?
If you are using the Transmission Atlas in conjunction with PowerWorld Simulator you can adjust generation and transmission, among other variables as needed for each project. Just like any Simulator one-line, the Transmission Atlas diagrams are completely modifiable to suit your modeling needs. PowerWorld Viewer however, is a freeware program that does not allow changes to be made to the displays.

What kind of detail is included?
The Transmission Atlas includes mapping of all the objects contained in the power flow cases for the TA-Eastern based on MMWG cases, ERCOT and WECC. Substations, transmission lines and load flow pie charts are included.

What are the geographic attributes of the onelines with Transmission Atlas?
Our primary emphasis is on being electrically correct; however we give a great deal of attention to the geographic placement of objects:

• Significant efforts are put forth to place each object as near as possible to its actual location;
• We do not claim to be geographically correct in all instances, in dense areas for example we must move objects some so they don't overlap and can be seen on the oneline;
• We use the a number of means of establishing the location to place objects, including printed maps, locations of cities, intersections, etc. - this all leads to good geographic placement of even the lower kV but not precise;
• Generators contained in the power flow cases are mapped as well;
• Much nicer bus diagrams, including:
• adjusted font sizes for better clarity as well as other visual improvements;
• better presentation of city bus diagrams;
• improved placement of buses within substations.


• MMWG (Multiregional Modeling Working Group) data is being being used for ISO-NE, NYISO, MAPP, ECAR, SERC, MAIN and MAAC. The benefits of this data are:
• it provides for better representation of areas around it as well;
• it will provide for better graphical representation of what effects will happen when a change occurs even on long distance transfers of power.