Ed Whittingham says he's taken a lot of hits for his views, and those blows are coming from both sides of the political aisle.

If you ask Alberta Premier Jason Kenney, Whittingham — a long-time environmental activist and former executive with the Pembina Institute think tank — is anti-oil and anti-jobs and someone who quit the province's energy regulator before he could be fired by the United Conservative Party government.

But if you talk to anti-oil activists this week, they might be surprised to hear Whittingham's supposedly in their camp after he professed support for Prime Minister Justin Trudeau's approval of the Trans Mountain pipeline expansion in a Globe and Mail op-ed.

Whittingham spoke to the Homestretch and CBC News at 6 on Wednesday, to share in his own words why as a life-long environmentalist he still feels building a pipeline is the right decision for Alberta and Canada.

This interview has been edited for length and clarity.

Q: So what do you think of the approval of the Trans Mountain pipeline expansion?

A: I think Ottawa made the right decision. I think TMX has been a very polarizing issue, and I think many in Canada and Alberta would agree, and it's been portrayed as an either-or proposition.

That is, you can either have the economic benefits that come with the pipeline or you can have action on climate change.

In the absence of [the Trans Mountain pipeline] we've had our economic backs up against the wall. - Ed Whittingham

I think that we've been able to thread the needle on a both-and proposition.

Q: So why do you think the Trans Mountain pipeline expansion is the right decision for Canada, right now?

A: I've had the benefit of spending a lot of time with CEOs of some of the biggest energy industries in the country, headquartered here in Calgary.

They've laid out very clearly that our industry needs to move from a high-carbon, high-cost quadrant with its oil, to a low-carbon, low-cost one. It's an existential challenge and one that we're up for.

To do that, you need to be in a position of financial strength.

So the Trans Mountain pipeline, in the absence of it right now we've had our economic backs up against the wall. It's going to create some of the financial capacity we need to make those investments, to retool our companies and our economy so we're competitive in a low carbon economy.

Q: What kind of reaction are you getting to your position?

A: As you might imagine, mixed. It's a tough time to be in the pragmatic, rational middle, particularly on this issue.

And if you're in the middle, you're going to take some shots.

But, hey, these views are my own and I felt it important to say what I think.

Q: What do you think of the federal government saying some of the profits will go toward green energy programs?

A: I think it's the right decision and this enhances the financial proposition with the approval.

What the prime minister committed to was investing not just the proceeds made from operating the pipeline, a pipeline that you and I and every Canadian owns, but also the sale proceeds. And those sale proceeds will be in the billions.

Q: Has the federal government done enough to address environmental concerns?

A: I think they have. There are important conditions in place on this.

One, although this might be unpopular with some Albertans, the federal government has committed to ensuring there's a carbon tax in place in Alberta and every dollar that's collected will be reinvested back in the province for things like energy efficiency upgrades, public transit, etc.

Two, they've been clear that the emissions limit has to stay. And either Alberta needs to move forward with regulating that hundred megaton oilsands emissions limit, which gives the world certainty on the overall GHG footprint of the oilsands, or that they're going to step in and ensure that's in place.

Q: What do you make of Alberta Premier Jason Kenney getting rid of the carbon tax?

A: I think it's the wrong move, frankly.

I think the federal government has been right to say, 'hey, this is a national proposition. If we're going to hit our Paris 2 C climate target, our international obligation, then we can't afford to take the most important tool off the table.

If you want to reduce pollution, put a price on it.

Pipe for the Trans Mountain pipeline is unloaded in Edson, Alta., on Tuesday. (Jason Franson/The Canadian Press)

Q: Federal Conservative leader Andrew Scheer released his climate change plan today and it does not include a carbon tax, but his approach appears to be to tax the heaviest polluters. What do you make of that program?

A: I'd call it half a plan.

It's great that he's maintained the commitment to price carbon emissions from industry.

It notably lacks a target.

We're also missing what CEOs and economists agree is the most important tool in the toolbox, and that is a carbon price.

Q: What would you say to the people of B.C., specifically the lower mainland, who are strictly opposed to any expansion of the oilsands?

A: I'd invite them to come to Alberta and say Albertans are trying their best to turn this ship around, to ensure our energy resources are competitive in a global, low carbon economy.

It's tough to do that when you can't make your mortgage payments.

Q: As an environmentalist, as an Albertan, do you put yourself in the optimist or pessimist column as to whether we can address climate change?

A: I'm probably an optimist to a fault, even when I'm taking punches for my views.

I have a tremendous amount of faith in Albertans, I've had the honour of living in this province for decades.

I'm very proud of what we've been able to do.

And that's why I decided to raise my voice and decided to say hey, on the balance of things, this pipeline is very important.