Part Total Ownership Cost Model      

The software on this web site was developed by the CALCE Electronic Products and Systems Consortium at the University of Maryland, College Park (Project Number: C09-24). The Part Total Ownership Cost Model is designed to estimate the total cost of ownership of a part or component existing in an OEM organization’s database.


Total Cost of Ownership is an approach employed to estimate the overall cost incurred by an organization in designing, manufacturing, managing, and sustaining a component from conception to obsolescence. The concept of total ownership costs can be applied to most (if not all) parts that are handled by OEM organizations. The value of this approach lies in the fact that lifecycle costs related to a component extends beyond the procurement price. Verification, testing, rework, inventory, handling, labor, etc. are only a few contributors toward ownership costs that accumulate over the entire time span that the part exists in an organization's database. The Part Total Ownership Cost Model, developed by CALCE at the University of Maryland, offers a generalized method of estimating a total cost of ownership for a particular part or component.

Total Cost of Ownership

The total cost of ownership estimation is a “bottom-up” cost analysis approach that is broken down into manufacturing, procurement and inventory, maintenance, and field use costs.  For more information, please refer to model documentation below.

Figure 1. Visual overview of the Part Total Ownership Model


V. Prabhakar and P. Sandborn, “A Part Total Ownership Cost Model for Long-Life Cycle Electronic Systems,” to be published  in International J. of Computer Integrated Manufacturing.  

V. Prabhakar and P. Sandborn, “Optimizing the Sourcing of Electronic Components for Long Life Cycle Systems,” Proceedings DMSMS Conference, Las Vegas, NV, October 2010.

P. Sandborn and V. Prabhakar, “An Electronic Part Total Ownership Cost Model,” Proceedings of the DMSMS Conference, Palm Springs, CA, September 2008.

P. Sandborn, V. Prabhakar, and B. Eriksson "The Application of Product Platform Design to the Reuse of Electronic Components Subject to Long-Term Supply Chain Disruptions," Proceedings of the ASME 2008 International Design Engineering Conferences & Computers and Information in Engineering Conference, New York, NY, Aug. 2008.

For monthly progress reports and detailed project information click here. Note: CALCE login and password is required.

Download Model

The Part Total Ownership Cost Model application and associated documentation can be downloaded from the following links.  You will be queried for a CALCE login and password when downloading the materials below.  If you do not have a login and password please contact; at this time, appropriate logins and passwords are available only for CALCE members and other organizations associated with the development of the Part Total Ownership Cost Model.

   Release Date    Model Version    Documentation    Release Notes

    January 16th, 2009

   PTOCM - Version 1

  • Maintenance Model

  • Inputs


   New Features:

  • Dual-sourcing

  • Sensitivity analysis

  • Model documentation

  • Save/Load Features

  • Restructured maintenance model

Important Note: The model has been developed and tested in Microsoft Excel 2003. The current model is only compatible with Windows versions of Excel and uses embedded VB macros. When prompted at startup, VB macros must be “enabled”.

For questions or problems contact:

CALCE Electronic Systems Cost Modeling Laboratory, University of Maryland, College Park

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Last Updated: January 13, 2011