The government is coming under pressure to introduce a windfall tax on energy companies before the budget.
The Social Democrats says it's immoral that energy firms are profiteering on the cost of living crisis, caused by the war in Ukraine.
Co-party leader Roisin Shortall said the government should consider introducing the tax on a long term basis.
"I think there is certainly an argument for that being a long term tax measure.
"Certainly in the short and medium term, at a time when inflation is running so high and there needs to be support provided for government, a windfall tax would provide those receipts for government to enable them to invest in measures such as retrofitting."
