N. GKOUMAS & SIA E.E. (distinctive title: G3 ENERGY) has been founded in 2005, as a result of its members’ cooperation since 2001. Upon the active involvement in Renewable Energy Sources (RES) projects development and particularly in the Wind energy and PV market, G3 has been paying ever since a close attention to the Greek RES market needs. Recently, G3’s activities are spreading in the field of household buildings’ and SMEs1 installations energy efficiency (EE).

Our senior managers have a cumulative professional experience more than 15 years as free-lance engineers in the RES field. G3 is consisting of experienced personnel, (i.e. Civil, Electrical and Mechanical Engineers, Environmentalists etc.), providing a complete project development, technical and consultant services directly related to RES and EE.

G3’s activities cover a wide range of services for both national and international clients including consulting, planning and project development. G3 Energy strictly follows the permission procedure of a RES and EE project from the beginning to the final delivery of the installation license to the investor. In the G3’s services are included the acquisition of all the intermediate permits required for the effective implementation of RES and EE projects (Wind, PV, Geothermal etc.), as well as the folder preparation and the application submission for eligibility in the subsidy for granting national programs according to the Greek investment regulatory framework.

Amongst others, G3 carries out the following works:

•    Elaboration of business plans including all the required studies (technical, financial, environmental, civil, etc.) and technical and financial evaluation on RES and EE investments

•    Follow up and project management until the completion of permitting procedure including the public relations with the local authorities and communities

•    Energy audits in household buildings and SME installations (including buildings energy management) for improvement their energy efficiency,

•    Feasibility studies for implementing the RES and EE plans on the households and SME buildings capacity.

•    RES systems (PV and GSHPs) dimensioning for supplying electricity and heating/cooling in buildings and industrial installations.


-Sustainable Buildings and districts
• Smart grid and energy systems integration  •    Energy saving

-Renewable Energies
•    Wind power technology  •    Photovoltaic solar Heating  •    Others – Renewable Energy

-Energy management
• Energy efficiency  •    Energy recovery  •    Heating system

•  Planning services  •    Other services