CALGARY -- The CEOs of Canada's two biggest pipeline companies say they are focused on lowering their operating greenhouse gas emissions while avoiding big oil pipeline projects in the wake of ongoing opposition throughout North America.

Both Francois Poirier of TC Energy Corp. and Al Monaco of Enbridge Inc. told the virtual 2021 Scotiabank CAPP Energy Symposium on Wednesday that repositioning their companies to account for the global energy transition to cleaner fuels is among their top priorities.

The decision by President Joe Biden to cancel TC Energy's Keystone XL pipeline permit in January was disappointing, but Poirier said TC Energy is building on learnings from the environmental commitment it made just days before the decision.

"We did not make our commitment to net-zero operations on Keystone XL as of the in-service date, and providing our own generation by 2030, lightly. There was a great deal of homework ... (and) those learnings are carrying over to now our existing asset base," he said.

Meanwhile, Monaco said regulatory and political obstacles to building pipelines are expected to continue to make new pipelines hard to build, which is something that should benefit current Enbridge investors.

"You'd think that makes pipe in the ground more valuable, and I think it will eventually, but the reason for that is it's very difficult to replicate our asset base and the reality is that in any energy scenario we can think of, our systems are going to be critical for a long time," he said.

Both companies are intent on buying or building renewable electricity sources for their pipeline pump stations and compression systems, the CEOs said.

Enbridge has set goals to cut its energy intensity by 35 per cent by 2030 and get to net-zero emissions by 2050.

TC Energy has the skills and means to reduce emissions through carbon capture, use and storage and by developing technologies to produce and store hydrogen, Poirier said.

"The transition can't come fast enough for us, from my perspective, but we have to pace it appropriately and I believe that natural gas and liquids (like oil) will continue to play a prominent role in the energy economy for decades to come," he said.

"So I think our existing assets will continue to be used and useful for quite a long time and generate a tremendous amount of cash flow that we're going to be able to redeploy into energy transition."

Poirier said TC Energy is continuing to consider its options in response to the cancellation of Keystone XL, while reiterating it expects to take a related "substantive" charge in its first-quarter financial results.

In the spring of 2020, the company approved spending US$8 billion to complete Keystone XL after the Alberta government agreed to invest about US$1.1 billion (C$1.5 billion) as equity and guarantee a US$4.2-billion project loan.

The 1,947-kilometre pipeline was designed to carry 830,000 barrels a day of crude oil from Hardisty, Alta., to Steele City, Neb., where it would connect with the company's existing facilities to reach the U.S. Gulf Coast refining centre.

Monaco said he's optimistic that Enbridge's $9.3-billion Line 3 pipeline replacement project will be in service as scheduled in the fourth quarter of this year, despite ongoing protests and legal challenges. It is expected to add about 370,000 barrels per day of export capacity from Western Canada into the U.S.

The company, meanwhile, continues to fight in court an order from Michigan Gov. Gretchen Whitmer to shut down its Line 5 pipeline through the Great Lakes by next month, arguing the state doesn't have that jurisdiction and that the conduit is vital to U.S and Canadian customers.

This report by The Canadian Press was first published April 7, 2021.