EXHIBIT 99.1


NEWS RELEASE	                      				FOR IMMEDIATE RELEASE

CONTACTS:
Susan Odiseos		                     			Gilles Alligner
Director of Corporate Communications 		Director of Communications
Trigen Energy Corporation          				ELYO
One Water Street					                  235 Avenue G. Clemenceau
White Plains, NY 10601-1009	         		92000 Nanterre, France
914.286.6628				                      	1 (33) 1 41 20 1293
914.441.4969 (cell)
                                       Jeffrey Zack
                                       Morgen Walke Associates, Inc
                                       212.850.5643


             TRIGEN AND ELYO ANNOUNCE DEFINITIVE AGREEMENT

White Plains, N.Y. and Nanterre, France - January 19, 2000
- - Trigen Energy Corporation (NYSE Symbol: TGN) and ELYO, an
energy subsidiary of the Suez Lyonnaise des Eaux Group, jointly
announced today that they have entered into a definitive
agreement for ELYO to purchase all the outstanding shares of
Trigen it does not already own for $23.50 a share in cash.
ELYO's subsidiaries currently own approximately 53% of Trigen
common stock.

The Trigen Board of Directors approved the merger agreement
after a Special Committee of independent directors, with the
advice of Credit Suisse First Boston and legal counsel, Troutman
Sanders, had determined that the transaction was fair to Trigen
shareholders.

Trigen will retain its name and headquarters in White Plains, N.Y.

Trigen also announced that effective today, Richard E.
Kessel, currently executive vice president, chief operating
officer and a director of Trigen, was elected president and chief
executive officer. Mr. Kessel joined Trigen in 1993, when the
company acquired United Thermal Corporation (UTC: NASDAQ) where
he was CEO.  He also serves as chairman of the board's executive
committee.  He succeeds Thomas R. Casten who has resigned to
pursue other interests.

Michel Bleitrach, chairman and chief executive officer of
ELYO, said, "We appreciate the invaluable contribution that Tom
Casten has made to Trigen's success.  Tom has built an
experienced management team, which will now be led by Rich
Kessel.  We have every confidence that Rich and his team possess
the skills and vision needed to address the energy outsourcing
needs of customers in the rapidly evolving energy markets of
North America."

Tom Casten stated "It has been an honor to lead Trigen
employees in developing energy systems that reduce costs and
pollution.  In this daunting pursuit, the men and women of Trigen
have continually exceeded my own expectations in changing the way
the world makes power.  Society will benefit from Trigen's
continued success.  I wish Trigen well as I address new
challenges."

Christine Morin-Postel has been elected a Trigen director
and appointed to the post of non-executive chairman, replacing
George Keane, who will remain a director of Trigen.  Ms. Morin-
Postel co-founded Trigen with Mr. Casten in 1986 and currently
serves as chief executive officer of Societe Generale de
Belgique, the parent company of ELYO and Tractebel.  She also is
a member of the executive committee of the Suez Lyonnaise des
Eaux Group.

Ms. Morin-Postel commented, "I am looking forward to my new
role at Trigen, working with Rich and all the employees of
Trigen.  I would also like to acknowledge Tom Casten's leadership
at Trigen for these many years."

Trigen is a leading developer, owner and operator of
industrial, commercial and institutional district energy and
combined heat and power (CHP) systems in North America.  The
company serves more than 1,500 customers with energy produced at
49 plants in 20 states, Canada and Mexico.
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