TransCanada increases ownership in TC PipeLines, LP

CALGARY, Alberta – February 21, 2007 – TransCanada Corporation (TSX, NYSE: TRP) (TransCanada) today announced a wholly owned subsidiary, TransCan Northern Ltd., has entered into an agreement to purchase 8,678,045 common units of TC PipeLines, LP (the Partnership) at US$34.57 per common unit. TransCanada’s investment of US$300 million represents 50 per cent of a US$600 million private placement of common units by the Partnership with new and existing institutional investors in the United States. A subsidiary of TransCanada will also invest approximately US$12 million in the Partnership to maintain its general partnership interest.

The Partnership will use the proceeds from the private placement to partially fund its proposed acquisition of a 46.45 per cent general partner interest in Great Lakes Gas Transmission Limited Partnership (Great Lakes).

The purchase of common units of the Partnership is conditional on the closing of the Partnership’s acquisition of Great Lakes. The acquisition is expected to close by the end of February, 2007, subject to standard closing conditions.

On closing, subsidiaries of TransCanada will own approximately 32 per cent of the Partnership and continue to be the sole general partner.

TC PipeLines, LP is a publicly traded limited partnership. Pending the closing of the acquisition of a 46.45 per cent interest in Great Lakes Gas Transmission Limited Partnership announced December 22, 2006, TC PipeLines, LP will have interests in more than 3,600 miles of federally regulated U.S. interstate natural gas pipelines including Northern Border Pipeline Company (50 per cent ownership) and Tuscarora Gas Transmission Company (99 per cent owned or controlled). For more information about TC PipeLines, LP, visit the Partnership’s website at www.tcpipelineslp.com.

TransCanada is a leader in the responsible development and reliable operation of North American energy infrastructure including natural gas pipelines and storage facilities, and power generation. For 50 years, TransCanada has transported the majority of Western Canada’s natural gas production to key Canadian and U.S. markets. On closing of the acquisition of the American Natural Resources Company and ANR Storage Company announced December 22, 2006, TransCanada’s network of wholly owned pipelines will extend more than 59,000 kilometres (36,500 miles), tapping into virtually all major gas supply basins in North America. TransCanada will also become one of the continent’s largest providers of gas storage and related services with approximately 360 billion cubic feet of storage capacity. A growing independent power producer, TransCanada owns, or has interests in, approximately 7,700 megawatts of power generation in Canada and the United States. TransCanada’s common shares trade on the Toronto and New York stock exchanges under the symbol TRP.

FORWARD-LOOKING INFORMATION

This news release may contain certain information that is forward-looking and is subject to important risks and uncertainties. The words "anticipate", "expect", "may", "should", "estimate", "project", "outlook", "forecast" or other similar words are used to identify such forward looking information. All forward-looking statements are based on TransCanada’s beliefs and assumptions based on information available at the time such statements were made. The results or events predicted in this information may differ from actual results or events. Factors which could cause actual results or events to differ materially from current expectations include, among other things, the ability of TransCanada to successfully implement its strategic initiatives and whether such strategic initiatives will yield the expected benefits, the availability and price of energy commodities, regulatory decisions, changes in environmental and other laws and regulations, competitive factors in the pipeline and energy industry sectors, construction and completion of capital projects, access to capital markets, interest and currency exchange rates, technological developments and the current economic conditions in North America. By its nature, such forward looking information is subject to various risks and uncertainties which could cause TransCanada's actual results and experience to differ materially from the anticipated results or other expectations expressed. For additional information on these and other factors, see the reports filed by TransCanada with Canadian securities regulators and with the United States Securities Exchange Commission. Readers are cautioned not to place undue reliance on this forward looking information, which is given as of the date it is expressed in this news release or otherwise, and TransCanada undertakes no obligation to update publicly or revise any forward looking information, whether as a result of new information, future events or otherwise, except as required by law.

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For further information, please contact:

Media Inquiries:

TransCanada
Shela Shapiro
(403) 920-7859 or Toll Free (800) 608-7859

Investor & Analyst Inquiries:

David Moneta/Myles Dougan
(403) 920-7911