Argument for taxing cars based on weight ‘compelling’, committee to be told

Cars are getting bigger and heavier, which is offsetting efficiency gains from technology improvements, says UCC academic

There is a “compelling argument” to include a car’s weight when calculating vehicle registration tax (VRT) on both fossil-fuel and electric vehicles (EVs), TDs and senators will be told.

University College Cork (UCC) academic Prof Hannah Daly is to make the remarks at the Committee on the Environment on Tuesday.

The committee is examining the implication of the trend in sales of larger vehicles such as sports utility vehicles (SUVs) on Ireland’s “carbon budget” which is aimed at cutting greenhouse gas (GHG) emissions as part of efforts to combat climate change.

Ms Daly, a professor in sustainable energy at UCC, is to tell the committee she is attending as an independent academic and is not speaking on behalf of any institution or funding body.


Her opening statement says car dependency is “extremely high, and is a leading driver of GHG emissions in transport” and that “cars are getting bigger and heavier, which is offsetting efficiency gains from technology improvements”.

Prof Daly will outline how larger cars “increase energy consumption and CO2 emissions in several ways” including requiring more energy to move and creating more carbon emissions at the manufacturing stage.

Her statement says: “There is a compelling argument to include weight and vehicle footprint in the calculation of VRT for both fossil-fuelled and electric vehicles.”

She says preliminary analysis undertaken by UCC found “introducing a policy measure to cut the CO2 intensity of new fossil-fuelled vehicles” from 2024 would “contribute substantially to addressing the projected overshoot of legislated sectoral emissions ceilings” contained in the carbon budget.

Prof Daly also says: “While greater GHG savings can be achieved from addressing the weight of fossil-fuelled cars, the increasing weight in EVs is also of concern.

“Currently, Irish vehicle taxation does not distinguish between EVs on the basis of efficiency, weight or size, which is a missed opportunity.”

She says: “Heavier EVs are less efficient and consume more electricity, putting additional strain on power generation and renewable electricity deployment.”

Prof Daly adds: “Speed is key to accruing carbon savings: enacting a policy to reduce the weight of new cars sold in 2024 has 28 times more impact than implementing that policy in 2030.”

She also says: “It is fairer and more effective to apply taxation at the point of initial sale, rather than over a car’s lifetime.”

It is unlikely that any such measure would be brought in as early as next year.

In July, government officials suggested that the Republic may need to introduce higher taxes for larger, heavier cars to help make up for about €1.5 billion in lost revenue per year as motorists switch to electric vehicles.

The idea was included in the tax strategy papers which are prepared before the budget.

However, Minister for Finance Michael McGrath subsequently played down the prospect of such a measure being introduced in the short term, while saying that “over time” the Government and future governments would have to consider how to provide for the expected loss in revenue.

Separately, the Committee on Housing will be discussing the ongoing review of the National Planning Framework (NPF) and the impact on climate targets and a number of organisations are expected to urge more compact growth of towns and cities.

Marie Donnelly, chairwoman of the Climate Change Advisory Council, will say the review of the NPF “offers an opportunity to rethink how Ireland approaches compact growth, increasing both its ambition and specificity in terms of how it is measured”.

She will say the target for compact growth in the current NPF is “insufficiently ambitious in its effort to facilitate the low-carbon transition in the transport sector.”

National Transport Authority chief executive Anne Graham will call for “development consolidation” to be emphasised in any update to the NPF, saying: “Higher-density urban forms enable more efficient public transport operation and reduces our level of car dependency, which will all work to reduce transport carbon emissions.”

Cormac McQuinn

Cormac McQuinn

Cormac McQuinn is a Political Correspondent at The Irish Times