The upgrades target a Building Energy Rating of B and 50% energy efficiency improvement.
A midlands school is one of six selected for the government's retrofitting programme this year.
41 have so far been upgraded under the Schools Energy Retrofit Pathfinder Programme.
Deep retrofitting is already underway to improve the energy efficiency of nine schools added in 2021.
Work will begin on a further six - including Scoil Mhuire in Abbeyleix - this summer.
The upgrades target a Building Energy Rating of B, 50% energy efficiency improvement and 51% emissions reduction.
The works typically involves upgrades to the building fabric including wall and roof insulation, doors and windows, air tightness improvements, LED lighting and heating upgrades as well as renewable technologies.
It is jointly funded with a €28 million budget from the Department of Education and Department of the Environment, Climate and Communications and administered by the Sustainable Energy Authority of Ireland (SEAI) and the Planning and Building Unit in the Department of Education with support from Limerick Clare ETB.
Launching the 2022 tranche, Education Minister Norma Foley said;
"This programme continues to assist the Department to identify and test solutions for decarbonised energy efficiency solutions in our schools and to support delivery of the new Climate Action Plan.
"It is enormously beneficial for the education sector and is paving the way for, and informing, a much larger national schools’ programme for the energy retrofit of schools built prior to 2008 as included in the National Development Plan.
"This collaborative programme is facilitating research on a range of typical retrofit options, that has proven the robustness and scalability of renewable solutions within the schools’ sector."
While Environment Minister Eamon Ryan added;
"The Schools Pathfinder programme continues to be highly successful in testing retrofit and decarbonisation solutions in schools across the county.
"The upgrades to these older and inefficient buildings are reducing schools’ energy use and greenhouse gas emissions.
"The upgrades also result in significant savings on energy costs.
"Young people have been pathfinders in their calls for climate action.
"I’m delighted that we are demonstrating what can be done in a practical way in our schools, which are at the heart of our communities."
CEO of the Sustainable Energy Authority of Ireland, William Walsh says;
"SEAI continues to support schools with energy efficiency through student workshops, resources (more than 50,000 students per annum) and energy management (1000 schools to date). This allows them to report energy data through our monitoring and reporting system (2,807 schools reporting in 2021)."