Echelon and Stonewater Control Systems To Deliver Real-Time Energy Intelligence to the Enterprise Using Echelon's Panoramix Platform

BALTIMORE, MD — March 18, 2003 — Today at the National Facilities Management and Technology (NFMT) Conference/Exposition in Baltimore, Maryland, Echelon Corporation and Stonewater Control Systems announced that they will be providing advanced energy use, monitoring and control applications to retailers, convenience store chains, utilities and other corporations. Stonewater, a leading supplier of software for remotely managing energy, intends to use Echelon's Panoramix™ enterprise platform to allow customers to acquire, manipulate and act upon critical energy data gathered from remote facilities by Echelon's i.LON™ 100 Internet Servers.

Stonewater's energy1st application, when used in conjunction with the Panoramix enterprise platform, can enable companies to conduct internal energy audits, manage demand-side energy reduction programs, and optimize energy consumption across hundreds or thousands of remote sites in real-time or on demand.

"Echelon has a unique position in the world of networking, building automation and control. They offer an open, robust, interoperable networking technology, tens of millions of installed devices, thousands of customers, and hundreds of authorized building integrators," said Gerd Nierlich, Stonewater's president and CEO. "Adding energy1st to the Panoramix platform should enable energy management solutions using a true standards-based infrastructure. This is control that extends from the Board Room, through the enterprise data center, all the way down to energy consuming and monitoring devices. We believe that energy1st and the Panoramix platform together will save customers money by moving away from proprietary and custom implementations, and this will attract the attention of CEOs and CFOs and will drive this market."

"We're very excited to work with Stonewater to bring to market energy applications based on our Panoramix enterprise platform," said Thor Iverson, Echelon's Panoramix Platform Group's vice president and general manager. "Energy management is a weak spot in most distributed enterprises because the definition of ┼ĺenterprise critical information' rarely includes the networks of everyday devices that are at the heart of both energy consumption and energy measurement. I believe that applications like Stonewater's energy1st, combined with the Panoramix enterprise platform and our end-to-end infrastructure for networks of everyday devices, will fundamentally change that perception and enable businesses to truly understand their energy consumption and reduce their energy costs."

About Stonewater Controls Systems

Stonewater Controls Systems is a privately held, Evanston, IL-based corporation. The company supplies turnkey applications, monitoring and control systems, consulting and engineering to the utility, commercial building and large energy user markets. Users of Stonewater's energy1st system include The Art Institute of Chicago, Praxair, Jorgensen and Associates, Prudential Towers and the Sacramento Municipal Utility District. More information about Stonewater can be found at http://www.stonewatercontrols.com.

About Echelon Corporation

Echelon Corporation is the creator of the LonWorks platform, the world's most widely used standard for connecting everyday devices such as appliances, thermostats, air conditioners, electric meters, and lighting systems to each other and to the Internet. Echelon's hardware and software products enable manufacturers and integrators to create smart devices and systems that lower cost, increase convenience, improve service, and enhance productivity, quality, and safety. Thousands of companies have developed and installed LonWorks products and more than 29 million LonWorks enabled processors have been shipped for use in homes, buildings, factories, trains, and other systems worldwide.

The protocol underlying LonWorks networks and the signaling technology used by Echelon's power line and free topology transceivers have been adopted as standards by the American National Standards Institute (ANSI). Echelon is also a founding member of the LonMark® Interoperability Association, an open industry forum of hundreds of leading manufacturers, integrators, and users dedicated to promoting the use of interoperable LonWorks devices. More information is available at http://www.lonmark.org. Further information regarding Echelon can be found at http://www.echelon.com.

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Echelon, i.LON, LonWorks, LonMark, the LonMark logo and the Echelon logo are trademarks of Echelon Corporation registered in the United States and other countries. Panoramix is a trademark of Echelon Corporation in the United States and other countries.

This press release may contain statements relating to future plans, events or performance. Such statements may involve risks and uncertainties, including risks associated with uncertainties pertaining to the timing and level of customer orders, development of markets for and demand for Echelon's products and services, including products based on the Panoramix enterprise platform; risks associated with the development and performance of applications based on Echelon's Panoramix enterprise platform, including energy and cost savings; risk associated with market acceptance of Stonewater's Panoramix integrated applications, development by Stonewater of Panoramix based applications; and other risks identified in Echelon's SEC filings. Actual results, events and performance may differ materially. Readers are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date hereof. Echelon undertakes no obligation to release publicly the result of any revisions to these forward-looking statements that may be made to reflect events or circumstances after the date hereof or to reflect the occurrence of unanticipated events.

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