CMS Energy Corporation's Panhandle Eastern Pipe Line Company Unit Announces Open Season For Firm Natural Gas Storage Service

HOUSTON, September 18, 2001 - CMS Energy Corporation (NYSE:CMS) today announced its CMS Panhandle Eastern Pipe Line Company subsidiary will conduct an open season to determine market interest in firm, high-deliverability natural gas storage service in the pipeline's market area.

"An open season is an effective mechanism to determine our customers' long-term needs and how Panhandle Eastern can best meet those needs as an open access provider of energy services," said Christopher A. Helms, president of CMS Panhandle Companies. "The outcome of this open season will help Panhandle Eastern plan for the future use and potential expansion of storage services."

CMS Panhandle Eastern will accept non-binding expressions of interest from 8:00 AM CCT September 18, 2001 until 5:00 PM CCT October 18, 2001 for firm storage service up to 100,000 Dth/day deliverability from potential new storage capacity up to 6.75 Bcf. The expressions of interest should be for 30-day, 50-day, 70-day and 90-day service under Rate Schedule FS. The level of firm storage service that may be made available is dependant on the combination of capacity and deliverability proposed in the expressions of interest. Panhandle Eastern will evaluate the expressions of interest to determine the greatest use of the deliverability and capacity available to the largest number of shippers and create the greatest economic value. Expressions of interest made during the open season should be for service for a minimum length of 5 years with service beginning no earlier than the summer injection season of 2003. At the conclusion of the open season, Panhandle Eastern will evaluate all expressions of interest to determine the feasibility of expanding its storage capacity, including requesting CMS Southwest Gas Storage Company to file for an expansion of its storage facilities.

CMS Panhandle Eastern reserves the right not to consider expressions of interest at rates less than its maximum tariff rates under Rate Schedule FS.

Information about the open season and a copy of the Firm Storage Open Season Bid Sheet is available online on Panhandle Eastern's Informational Postings under "Notices" – "Non-critical" (msrpost.panhandleenergy.com/PeplFrameset.asp), or through CMS Energy's website (www.cmsenergy.com), or by contacting CMS Panhandle Eastern's customer service group at 800/275-7375 for a faxed or mailed copy. If you have specific questions regarding the open season please contact Randy Parr, Director, Marketing at 713/989-7623 or contact your marketing representative.

CMS Panhandle Companies, which includes CMS Panhandle Eastern Pipe Line Company, CMS Trunkline Gas Company, CMS Trunkline LNG Company, CMS Sea Robin Pipeline Company, and CMS Southwest Gas Storage Company, operates about 10,900 miles of mainline natural gas pipeline extending from the Gulf of Mexico to the Midwest and Canada. These pipelines access the major natural gas supply regions of the Louisiana and Texas Gulf Coasts as well as the Midcontinent and Rocky Mountains. The pipelines have a combined peak day delivery capacity of 5.4 billion cubic feet per day, 85 billion cubic feet of underground storage facilities and 6.3 billion cubic feet of above ground liquid storage facilities.

CMS Energy Corporation has annual sales of more than $14 billion and assets of about $16 billion throughout the U.S. and around the world with businesses in electric and natural gas utility operations; independent power production; natural gas pipelines, gathering, processing and storage; oil and gas exploration and production; and energy marketing, services and trading.

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For more information on CMS Energy, please visit our website at: www.cmsenergy.com

Media Contacts: Kelly M. Farr, 313/436-9253 or John P. Barnett, 713/989-7556
Investment Analysts Contact: CMS Energy Investor Relations, 517/788-2590