According to the energy balance of 2017, the energy consumption related to buildings in Greece amounts to 660522 Ktoe, a quantity that corresponds to 42% of the total final energy consumption in the country. The aim of the national strategy is to facilitate the cost-effective conversion of existing buildings into buildings with almost zero energy consumption with specific interventions that start from the shell and end in the electromechanical systems. This is an ambitious plan if we take into account that in order for the building stock to be in line with the climate neutrality targets in 2050, the final energy consumption in buildings must be reduced by 8% compared to 2015 and the percentage this to reach 40% in 2050.
Objectives and key interventions
In terms of energy consumed by buildings, among homes, the most energy-intensive buildings are detached houses, while apartment buildings have an average annual consumption of primary energy equal to 257.08 kWh / m2. In the tertiary sector, public assembly buildings are the most energy-intensive (average annual primary energy consumption 778.24 kWh / m2), as well as penitentiary buildings (average annual primary energy consumption equal to 622.67 kWh / m2) in almost all climatic zones.
Technical studies indicate that upgrading only the building shell can significantly contribute to the overall energy savings of the building, in percentages that can range from 25% to 75% of the total energy saved from partial or radical renovation of the building, depending on climate belt and its use. By 2030, the shell of 23% of the old residential buildings should have been upgraded in energy, while this percentage should almost double by 2040 to reach 50% in 2050).
In combination with the renovation of the building shell, the renovation of the energy systems for house and water heating, and to a lesser extent for cooling and cooking, is an important factor in achieving the energy saving goals. While the upgrade of the building shell ensures the reduction of energy needs for heating and cooling, the upgrade of energy systems contributes to the further reduction of energy demand due to the increase of system efficiency, but also to ensure almost zero emissions through the use of zero energy forms. carbon footprint. By combining the two forms of intervention, the building sector can contribute to the path to climate neutrality. Specifically, the conversion of energy heating systems is a priority in the domestic sector since in 2015 the heating systems occupied a share equal to 61% of the final consumption. By using more efficient systems this share will be reduced in 5130 to 51% according to the ESEK-2030.
