The Government cannot be "absolutely certain" there will be no power outages this winter, Eamon Ryan has warned.
The Minister for the Environment, Climate Action and Communications said electricity supply is tight, but that the Government will be able to manage it.
The Green Party leader warned this winter and subsequent winters will be difficult, adding it will be a balance of supply and demand.
He said he is confident there will be additional back-up power as there are ongoing discussions with companies about the volume of power Ireland needs.
Supplier EirGrid warned it will be unable to generate enough electricity in the coming years to meet a rapid increase in demand.
It said emergency measures are needed to secure the country's electricity supply.
Earlier this year, it was warned the country could face rolling blackouts this winter due to energy shortages, but these fears were allayed by news that two major electricity plants will reopen in the autumn.
EirGrid said it is dependent on the stations in Dublin and Cork reopening, but it expects system alerts to be a feature over the coming winters.
Mr Ryan told RTÉ Morning Ireland on Wednesday: "It is tight and you can't be absolutely certain but we expect to be able to manage it.
"But this winter and the subsequent winters will be difficult. We know what we need to do. We will have further options next year which looks to bring additional back-up power into place."
He also said renewable power like wind is being developed to help Ireland meet its climate targets.
Mr Ryan said Ireland is talking to various energy companies to make sure they can rely on the supply.
He also said there are a range of ways to address the supply shortage.
"It is on the demand side and the supply side so it's about flexibility, particularly some of the large industry providers, who are part of the solution," he added.