The Alaska Pipeline Project Begins Its Open Season

ANCHORAGE, ALASKA -- (MARKET WIRE) -- 04/29/10 -- The Alaska Pipeline Project announced today that it will commence the first natural gas pipeline open season to develop Alaska's vast North Slope natural gas resources on April 30. Separate but coordinated open seasons will be conducted simultaneously in Alaska and Canada.

The Alaska Pipeline Project is a joint effort between TransCanada Corporation (TSX: TRP) (NYSE: TRP) and Exxon Mobil Corporation (NYSE: XOM) to develop a natural gas pipeline under the Alaska Gasline Inducement Act (AGIA).

The Alaska Pipeline Project's open season offering will be assessed by potential shippers over a three-month period from April 30 through July 30, 2010. The project has provided information to potential shippers in Alaska and Canada on its anticipated engineering design, commercial terms, estimated projects costs and timelines. Shippers will assess this information and determine their interest in making long-term, contractual commitments to reserve capacity on the pipeline.

Two options will be provided in the Alaska Pipeline Project open season. The first option is a pipeline from Alaska's North Slope, through Alaska, the Yukon Territory and British Columbia, to Alberta, Canada, a distance of approximately 1,700 miles (2,737 kilometres), where the gas can be delivered on existing pipeline systems serving major North American markets.

The second option would transport natural gas from the North Slope to Valdez, Alaska, a distance of approximately 800 miles (1,287 kilometres), where it would be converted to liquefied natural gas in a facility to be built by others and then delivered by ship to North American and international markets.

Both options would provide opportunities for Alaska communities to acquire natural gas from a minimum of five delivery points on the pipeline. The Alberta option would additionally provide the opportunity for local natural gas deliveries in Canada.

A world-class gas treatment plant (GTP) and Point Thomson natural gas transmission pipeline are components of both options. The GTP would be built next to the North Slope's Prudhoe Bay facilities to treat the gas so it can be shipped on the pipeline. An approximately 58 mile (93 kilometres) pipeline would connect the natural gas supplies of the Point Thomson field to the plant and pipeline.

Only one of the two project options will advance and it is anticipated that the results of the open season will determine the preferred option.

For more information on the Alaska Pipeline Project, visit the project website at: www.thealaskapipelineproject.com.

To view a fact sheet for The Alaska Pipeline Project, click the following link: http://media3.marketwire.com/docs/Alaska%20Pipeline%20Project_Jan2010.pdf

To view a fact sheet for The Alaska Pipeline Project Open Season, click the following link: http://media3.marketwire.com/docs/OpenSeason_LR2.pdf

About TransCanada

With more than 50 years' experience, TransCanada is a leader in the responsible development and reliable operation of North American energy infrastructure including natural gas pipelines, power generation, gas storage facilities, and projects related to oil pipelines. TransCanada's network of wholly owned pipelines extends more than 59,000 kilometres (36,500 miles), tapping into virtually all major gas supply basins in North America. TransCanada is one of the continent's largest providers of gas storage and related services with approximately 370 billion cubic feet of storage capacity. A growing independent power producer, TransCanada owns, or has interests in, over 11,800 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. For more information visit: www.transcanada.com

About ExxonMobil

ExxonMobil is the world's largest publicly traded international oil and gas company, providing energy that helps underpin growing economies and improves living standards around the world. ExxonMobil uses innovation and technology to deliver energy to a growing world. The company operates facilities or markets products in most of the world's countries and explores for oil and natural gas on six continents. For more information visit: www.exxonmobil.com

TransCanada 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", "believe", "may", "should", "estimate", "project", "outlook", "forecast" or other similar words are used to identify such forward-looking information. Forward-looking statements in this document are intended to provide TransCanada security holders and potential investors with information regarding TransCanada and its subsidiaries, including management's assessment of TransCanada's and its subsidiaries' future financial and operations plans and outlook. Forward-looking statements in this document may include, among others, statements regarding the anticipated business prospects and financial performance of TransCanada and its subsidiaries, expectations or projections about the future, and strategies and goals for growth and expansion. All forward-looking statements reflect TransCanada's beliefs and assumptions based on information available at the time the statements were made. Actual results or events may differ from those predicted in these forward-looking statements. Factors that could cause actual results or events to differ materially from current expectations include, among others, the ability of TransCanada to successfully implement its strategic initiatives and whether such strategic initiatives will yield the expected benefits, the operating performance of TransCanada's pipeline and energy assets, the availability and price of energy commodities, capacity payments, regulatory processes and decisions, changes in environmental and other laws and regulations, competitive factors in the pipeline and energy sectors, construction and completion of capital projects, labour, equipment and material costs, access to capital markets, interest and currency exchange rates, technological developments and the current economic conditions in North America. By its nature, 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 expectations expressed. Additional information on these and other factors is available in the reports filed by TransCanada with Canadian securities regulators and with the U.S. Securities and Exchange Commission (SEC). Readers are cautioned to not 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 to not use future-oriented information or financial outlooks for anything other than their intended purpose. 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.

ExxonMobil Cautionary Statement

Estimates, expectations, and business plans in this release are forward-looking statements. Actual future results, including project plans, schedules, and costs and production rates, resource recoveries, and capital expenditures could differ materially due to changes in market conditions affecting the oil and gas industry or long-term oil and gas price levels: political or regulatory developments; the outcomes of negotiations; timely completion of development project; reservoir performance; technical or operating factors; and other factors discussed under the heading "Factors Affecting Future Results" under the "investor" tab on our website (www.exxonmobil.com) and in Item 1A of our most recent Form 10-K. Reference to quantities of natural gas and similar terms include volumes that are not yet classified as proved reserves under SEC definitions but that we believe will be produced in the future.

Contacts:
TransCanada
Media Inquiries
Cecily Dobson/Terry Cunha
(403) 920-7859 or (800) 608-7859

Investor & Analyst Inquiries
David Moneta/Myles Dougan/Terry Hook
(403) 920-7911 or (800) 361-6522
www.transcanada.com