Environmentalists say revenue raised from the hike in the carbon tax should be used to help people switch from fossil fuel to cleaner renewables.

The increase that comes in today adds €1.20 to the price of a 40 kilo bag of coal, and more than 20c to a bale of briquettes.

It comes despite calls on the government to defer the hike, the second in the space of two years. Campaigners say it will disproportionately hit the elderly.

Pat Finnegan of the Greenhouse Ireland Action Network told Newstalk's Breakfast the tax is a 'public bad' that should and could be used for good, since climate taxes now raise €500m in the year.

Currently that money isn't ring-fenced, meaning the government can decide how to spend it. Mr. Finnegan would like a national decarbonisation fund to be established, with a view to helping pensioners switch to renewables and efficient home heating options:

Mr. Finnegan has also countered criticism by insisting the price increases were well-flagged and nobody should be shocked.

Age Action Ireland

Meanwhile, Eamon Timmins of Age Action Ireland has appealed to the government to increase payments to older people to help with their winter fuel bills: