Environmentalists say revenue raised from the hike in the carbon tax should be used to switch the focus to cleaner fuels.
The increase which comes in to force today will add €1.20 to the price of a 40 kilo bag of coal - and 26 cent on a bale of briquettes.
It comes despite calls on the Government to defer the hike, the second in the space of two years.
Pat Finnegan of the Greenhouse Ireland Action Network said the tax was a good thing, but should be used to improve energy efficiency and environmental measures.
"Our case all along has been to use the carbon tax (revenues) to switch into renewables," he said," to de-carbonise out transport (for example), and get electric cars going."