Energy saving measures are of principal importance for the protection of the environment and for the gradual reduction of our dependence on fossil fuels. In Greece, energy consumption in buildings accounts for 1/3 of the total energy consumed.

Among the measures that were taken for the improvement of the energy efficiency in buildings was the issuance of the Energy Performance Regulation for Buildings (ΚΕΝΑΚ). This Regulation, among other things, specifies the methodology for the calculation of the energy efficiency in buildings, sets minimum requirements for the energy efficiency of new and renovated buildings and introduces the energy inspector and the energy performance certificate.

The energy performance certificate is a document which certifies a building’s energy rating and points out possible energy efficiency improvement measures. Before the issuance of an energy performance certificate for a building, the building’s energy audit is conducted by an accredited energy inspector.

An energy audit is a systematic procedure which is conducted by accredited energy inspectors and aims at the following:

• The determination and documentation of a building’s energy profile and energy rating.

• The issuance of the Energy Performance certificate.

• The identification of cost-effective solutions for improving the energy efficiency of a building.

In order to conduct an energy audit some initial data regarding the building must be provided to the energy inspector by the owner of the building (e.g. general information about the building, architectural and electromechanical drawings). In addition, an on-site visit of the energy inspector must be conducted so that the data initially provided can be verified and documented. In cases of large buildings with complicated electromechanical installations appropriate measuring equipment can be employed in order to measure various parameters.

The energy audit of the heating or air-conditioning system of a building is the process of evaluating the efficiency of the system, estimating the size in relation to the building’s needs for heating, cooling and ventilation and making recommendations with the aim of improving the system’s energy efficiency. According to the legislation in force, for buildings with boilers with installed power between 20 kW and 100 kW an energy audit of the heating system should be performed every 5 years. In addition, for buildings with air-conditioning systems exceeding 12 kW in total, an energy audit of the system should be performed every 5 years.