Use of Sustainable Energy Sources and Technologies in Primary and Secondary School Buildings in Greece. Can They Eliminate their Carbon Footprint?

School buildings consume energy covering their energy demand. The most of them utilize fossil fuels and grid electricity while the use of renewable energies is rather limited. School buildings should eliminate their carbon emissions in order to achieve the global target for net-zero carbon emissions by 2050. The energy consumption and the carbon emissions in schools have been evaluated. School buildings in Greece consume less than 100 kWh/m² year. Solar thermal energy, solar photovoltaic energy and high efficiency heat pumps can cover all the energy demand in school buildings in Greece replacing the use of conventional energy sources. These energy technologies are reliable, mature and cost-effective. There are 7,756 primary and secondary school buildings in Greece consuming 1.67 TWh/year. The total cost of energy renovation eliminating their carbon emissions is estimated at 1,156,000 €/school or 8.96 billion € for the 7,756 schools in the country. For achieving the target of net-zero carbon emissions by 2050, 310 Greek schools should be energy refurbished every year eliminating their carbon footprint in the next 25 years. Taking into account the availability of benign energy sources and technologies the main barrier for eliminating the carbon emissions in school buildings in Greece by 2050 is the high investment cost. Our results could be useful for the development of the required policies for decarbonization in school buildings.