Consensus proved impossible to reach this week, when it came to agreeing on a landmark deal to tackle climate change and reduce greenhouse gas emissions.

The issue which divided TDs and Senators was the expected one - carbon taxes.

To a certain extent, the row makes no difference: the Joint Oireachtas Committee passed its substantial Climate Action report by a large majority on Thursday night, and this policy road-map will significantly influence Government policy for years to come.

However, in narrow political terms, this is a beginning rather than an end. Carbon taxes are set to become an election issue - whether that's Local, European or General.

Yet before analysing what divided the parties on climate policy, it's really important to highlight what united them. There are far-reaching recommendations contained in the report which, if implemented, could have a profound impact.

Take, for example, the recommendations on governance.

It may sound boring, but this has been a critical failure of Irish politics for decades when it comes to climate action. The absence of joined-up thinking partly explains why our country has failed so miserably to reach its EU emissions reduction targets. Plans were made, but no-one was ever held to account when it came to delivery.

This new report identifies the critical flaw and has a strategy to eliminate the problem.

First, it lays the responsibility for delivering climate change policy at the door of the Taoiseach. Second, it demands that the Finance Minister introduces a 5-year carbon budget. And third, it calls for the Climate Action Committee to receive powers of scrutiny akin to the powerful Public Accounts Committee.

If implemented, these measures would make a significant difference. Committee Chair and Fine Gael TD, Hildegarde Naughton, said these improvements would be "... key in ensuring that climate matters are elevated to the same level of importance as the economy".  

The document, which took 7 months to compile and includes 40 different recommendations, is stuffed full of other innovative ideas. It will be a real tragedy if it ends up being remembered for only one thing.

Yet carbon tax is divisive. And that division was on show on Thursday night. Within half an hour of the Committee approving their document, Sinn Féin produced a 'minority report' which outlined in technicolour its position.

The party was, it said: "... clear and unambiguous on the issue of increases in carbon tax - we are absolutely opposed to them."

Sinn Féin believes that carbon taxes have proven to be ineffective; to hit lower-income earners hardest; and that big industry should be picking-up the tab anyway.

Brian Stanley, TD, said a carbon tax has been in place in Ireland for years, but emissions have still "gone through the roof."  

People Before Profit also opposed the final report. It's representative on the Committee, Bríd Smith, who is well-regarded by climate campaigners, submitted multiple amendments to the report.

However, ultimately, she too voted against the deal.  

And her her party also issued a statement within half an hour of the report being finalised. It stated that while the document had "good suggestions and recommendations", People Before Profit had opposed it because, it argued, the report had  "... only one actionable suggestion that is likely to see the light of day - an increase in carbon taxes."

For the previous 48 hours, the report looked as if it would not even secure a majority due to Fianna Fáil concerns over carbon tax. The party was demanding that money raised by green taxes would have to be reinvested in helping avoid fuel poverty and assisting affected communities.

Concern over avoiding what's called 'fuel poverty' is repeatedly mentioned in the report. The Committee wanted to ensure it didn't pile charges on people who already can't afford to keep themselves warm, or who wouldn't be able to keep their car on the road.  

Eventually, a compromise was hatched by the Greens, Labour, Fine Gael and Fianna Fáil which retained a recommendation from the State's Climate Advisory Council that the carbon tax of €20 per tonne be increased to €80 per tonne by the year 2030.

This would roughly translate into a bag of coal increasing in price from €16 to €24 over the next 11 years, or a bale of briquettes jumping from €5 to €7 or more.

Fianna Fáil's Timmy Dooley was keen to point-out that his party agreed to the measure only after insisting that "... prior to... any increase in carbon tax, the Government will have to introduce specific policy measures to protect those who may not be able to transition away from fossil fuels due to fuel poverty."

Labour's Sean Sherlock was also live to the need to reassure the public that a carbon tax hike would be fair. He said: "Labour has fought to ensure that workers and communities are not left behind as we make the necessary changes to the economy."

In other words, all sides were keenly aware of the political risk associated with increasing taxes and charges. No politician will ever forget the anti-water-charges protests, nor how Solidarity's Paul Murphy surprised Sinn Féin by taking the 2014 Dublin South West by-election seat.

Yet, the political battles ahead will not focus on the scale of the hike in carbon tax alone, but also on how it is implemented. The Taoiseach, Leo Varadkar, has already outlined his plans.

In contrast to the 'pay-up-or-else' strategy adopted over water-charges, Mr Varadkar has advocated what's termed a "fee-and-dividend" approach in which consumers get a credit from the Government for taking action and changing their behaviour.

This has been branded as a 'gimmick' by Fianna Fáil's Timmy Dooley, but it is a crafty political calculation: if those who can't afford to pay are sent an annual cheque by the Government, and those who can pay get tax credits for changing their behaviour - then who is going to march in the streets to oppose the measure?

The Sinn Féin President, Mary Lou McDonald, decried this approach in the Dáil during the week - branding the Taoiseach's proposal a 'make-believe' strategy which had already failed in Canada and Norway.

Mr Varadkar shot-back that Sinn Féin was "not being honest" on climate change because it constantly dodged tough decisions. He sniped: "We all know the far-left is anti-environment."

That sharp exchange foreshadows a real, and possibly vicious, political battle ahead. Then again, maybe the climate change issue is different.

I say that because sitting in the public gallery on Thursday was a group of students from the Fridays For Futures movement, inspired by 16-year-old Swedish activist, Greta Thunberg. These climate activists have political clout - managing to get thousands of protesters to descend on the Dáil earlier this month.

Their political power was underlined by the fact that 5 of the student climate leaders were allowed to address the Committee for 2 minutes each.

The first thing which was obvious from the students was the absence of any deference to the politicians - they came in, sat down, and fired salvo after salvo: the politicians were not doing enough; they were not acting quickly enough; and their 'empty words' would not be tolerated anymore.

But maybe the contribution which resonated most with the TDs and Senators, in an uncomfortable way, came from 16-year-old Conal O'Boyle from Donegal.

Climate change, he said, was far more important than Brexit. The message from the 15,000 Irish students who protested in Dublin, part of 1.3 million teenagers who went on strike globally, has now to "come through these thick walls of Leinster House."

And then he hit them with his best punch: his generation would soon be able to vote and the climate strikers would rock the system to the core. "You will know about it" he concluded.

One of Conal's TD's - the Independent Thomas Pringle - was on the Climate Action Committee and he appeared to have listened to his constituent's message. 

While Mr Pringle voted against the inclusion of a carbon tax on the basis that he didn't want to give the Government a "blank cheque", he voted in favour of the final report. 

Asked to explain his voting pattern, he told RTÉ: "I felt that it’s more important to support the report. I made my point I felt [on the tax]. The report is vitally important - more important than Fine Gael or Fianna Fáil or any of us."