• The formation of planning policies for RES projects,
• The establishment of rules and standards for the development of efficient RES installations and their harmonious penetration into the environment, and
• The creation of sufficient mechanisms of RES planning.
Last, the Specific Framework of Planning Design and Sustainable Development for the Renewable Energy Sources is expected to decrease the difficulties of land selection and to lessen bureaucratic bottlenecks.
During 2008, four large wind farms were installed, having capacities in the range of 15 MW to 24 MW each. The total installed capacity of wind energy generators reached 990 MW. The electricity sector operates within the framework set by Law 2773/1999 “Liberalisation of the electricity market—regulation of energy policy issues and other provisions” (Official Gazette A 286).
This law was enacted for the transposition of Directive 96/92/EC for the liberalization of the electricity market (OJ L27/30.1.1997). The basic law was revised by Law 3175/2003, “Exploitation of the geothermal potential, district heating and other provisions” (Official Gazette A 207) and Law 3426/2005, “Precipitation of the liberalisation process of the electricity market” (Official Gazette A 304).
Today, the RES deployment regime is governed primarily by Law 3468/2006, “Generation of electricity from renewable energy sources and through high-efficiency co-generation of electricity and heat and miscellaneous provisions” (Official Gazette A’ 129). The text of the law and its circular D6/F1/oik.21691/30.10.2006 are posted on the Ministry of Development web site (http://www.ypan.gr).
The list of prices is based on the price in euros per megawatt-hour (Wind onshore 80.14 €/MWh; Wind offshore 97.14 €/MWh) of electric energy absorbed by the grid, including the grid of non-interconnected islands.
Progress Toward National Objectives
Apart from the obvious environmental and social benefits of using renewable energy sources, the economic benefits from their development are huge, as they gradually promote Greece’s independence from imported energy and finite fuel sources.
Benefits to National Economy
Wind energy represents an enormous opportunity to attract foreign investments into Greece and is also a challenge for the country’s business world. In the last decade, interest has increased among, mainly, construction companies and individual investors for wind energy–related projects.
Wind energy deployment has become a challenging area for development all over the country—especially in areas having poor infrastructure, in which some of the most promising sites for wind energy development can be found. Although manufacturing of wind turbines has not been established in Greece, there is considerable domestic added value in connection with infrastructure works, for example, grid strengthening, tower manufacturing, road and foundation construction, civil engineering works, and so on. In addition, new jobs are created related to maintenance and operation of the wind farms in mainly underdeveloped areas. An expanding network of highly experienced engineering firms has been created and is currently working on all phases of the development of new wind energy projects. Thus, wind energy is gradually becoming a considerable player contributing in the development of the country.
Industrial development and operational experience
No significant manufacturing developments occurred in 2008 apart from the continuing involvement of the Greek steel industry Electricity Market, sets an indicative target for Greece to cover a part of its gross national electricity consumption by 2010 from RES equal to 20.1%, with the contribution of large-scale hydroelectric plants included. This target is also compatible with the international commitments of Greece resulting from the Kyoto Protocol. Based on expected electricity consumption in 2010, production of electric power from RES on the order of 14.45 TWh (including large-scale hydroelectric plants) is set as the goal for 2010. To meet these goals, the installed capacity of wind farms should reach the level of 3,193 MW, and the corresponding energy generated should be on the order of 8.1 TWh.
In 2008, the installed capacity of the wind turbines reached 990 MW, showing an increase over the previous year of 13%. In 12 separate projects, a total of 72 wind energy conversion systems, with an installed capacity of approximately 115 MW, were connected to the electricity supply network. The current estimation of wind energy production in 2010 ranges between 2,040 MW (conservative scenario) and 3,193 MW (optimistic scenario) (1).
The energy produced from wind turbines during 2008 was approximately 2,300 GWh. The energy produced in the previous five years was 1,873 GWh (2007), 1,683 GWh (2006), 1,270 GWh (2005), 1,130 GWh (2004), and 1,020 GWh (2003).
The average capacity of wind turbines installed in 2008 was 1,657 kW, while the average capacity of all the wind turbines operating in the country was 832 kW. Wind farm malfunctions that have been reported up to now are mainly related to gearbox failure and lightning strikes. No major events leading to extensive wind farm outages have been reported.
The total cost of wind-power projects depends on the wind turbine type, size, and accessibility. This cost ranges from 1,000 to 1,200 €/kW and is mainly influenced by international market prices and interconnection costs. The cost of generated wind power could be assumed to be between 0.026 and 0.047 €/kWh, depending on the site and project cost. The typical interest rate for financing wind energy projects is 7% to 8%.
In the liberalized electricity market, as well as before, a single price exists in the so-called interconnected system and in the autonomous systems, depending on the identity of the consumer and the voltage class. This price list concerns the tariffs of electricity purchased since August 2006 by the Hellenic Transmission System Operator according to Law 2244/94; the decision of the Minister of Industry, Energy and Technology; and Law 2773/99. This electricity either is produced by independent producers or is the surplus of auto-producers and comes from either RES or CHP. There is no capacity charge on purchases from producers in non-interconnected islands.
National Incentive Programs
Until 2008, financial support for wind energy projects was provided by the state within the framework of the Operational Program for Competitiveness (OPC), 2000–2006, and the Law for Development 3299/2004. The OPC raises resources from the Third Community Support Framework to provide public aid to renewable energy sources and energy saving, substitution, and other energy-related actions. As 2008 was the ending year of the Third Community Support Framework, most of the projects financed by the OPC have been finalized. Within the OPC, 29 wind energy projects of 468 MW total installed capacity have been approved. Twenty of them (295 MW total installed capacity) were successfully finalized, providing approximately 700 GWh/year to the national grid.
In January 2008, the Greek Ministry of Economy and Finance announced a new program entitled National Strategic Development Plan (NSDP), 2007–2013. The NSDP raises resources from the Fourth Framework Programme to reinforce the investment activities of the private sector and strengthen the productive potential of the country. Additionally, financial support for wind energy investments is foreseen through the Law for Development 3299/2004, which provides grants of up to 40% of the total investment.
The Ministry for Development promotes all R&D activities in the country, including applied and basic R&D as well as demonstration projects. Key areas of R&D in the field of wind energy in the country are wind assessment and characterization, standards and certification, wind turbine development, aerodynamics, structural loads, blade development, noise, power quality, wind desalination, and autonomous power system integration. There is limited activity in Greece concerning offshore deployment.
CRES (Center for Renewable Energy Sources) is the national organization for the promotion of renewable energy in Greece. It is mainly involved in applied R&D in the fields of aerodynamics, structural loads, noise, power quality, variable speed, wind desalination, standards and certification, wind assessment, and integration. CRES has developed and operates its Laboratory for Wind Turbine Testing, which has been accredited under the terms of ISO/IEC 17025:2000.
Several research projects were running at CRES during 2008, co-funded by the European Commission and the Greek Secretariat for Research and Technology. These research projects had the following goals:
• Characterizing the main features of complex or mountainous sites and identifying the crucial parameters affecting both the power performance and the loading of different types of wind turbines operating in such environments
• Developing wind turbines for installation in hostile environments
• Improving the damping characteristics of wind turbine blades
• Developing new techniques for power quality measurement and assessment
• Increasing understanding of wind turbine standardization procedures
• Developing blade material testing techniques in the in-house experimental facility
• Understanding generic aerodynamic performance of wind turbine blades through computational fluid dynamics (CFD) techniques
• Developing cost-effective micrositing techniques for complex terrain topographies.
In the Laboratory for Wind Turbine Testing of CRES, the project titled “Development of Infrastructures and Laboratory Support of CRES” (Measure 4.2, Action 4.2.2, of the operational program “Competitiveness”) ensures the update of its equipment and services. The project involves the optimization and integration of equipment and services related to power quality measurements, load measurements, wind speed measurements, and so on. Two of the most significant purchases by the CRES Wind Turbine lab under this project were the continuous-wave light detection and ranging system (LIDAR) Zephyr from Qinetiq and the pulsed-wave LIDAR (windcube mode) from Leosphere, for wind speed measurements up to 150 m and higher. The project was completed in September 2008.
CRES is responsible for the development of the New Wind Map of Greece, which aims at the exploitation of country’s wind potential and at the promotion of wind energy technology through new investments. The work involves the installation of 40 new masts. The Regulatory Authority for Energy (RAE) assigned the development of the map to CRES. The project was completed at the end of 2008.
Basic R&D on wind energy is mainly performed at Greece’s technical universities. The Fluids Department of the Mechanical Engineering school of the National Technical University of Athens (NTUA) is active in the fields of wind modeling, rotor aerodynamics and aeroelasticity, load calculation, fatigue analysis, noise, and wind farm design.
Since 2007, NTUA, in collaboration with CRES, developed a new eigen value stability tool for the analysis of the complete wind turbine in closed-loop operation (i.e., including the control loop). Also, NTUA participated in the EC-funded project UPWIND, which is aimed at developing the computational framework for the design of future large-scale wind turbine applications (beyond the current 5-MW scale). Within this project, NTUA developed and tested new aeroelastic tools capable of treating the large deflections anticipated in future large-scale highly flexible blades. New load control techniques such as a trailing edge flap have also been tested in the context of advanced 3-D aerodynamic modeling using the in-house free wake code GENUVP.
In 2008, the Electric Power Division of NTUA continued its research activities on renewable and distributed energy resources, focusing on several aspects of their technologies and grid integration issues. Specific research areas include the following:
• Microgrids with high penetration from distributed energy resources, concentrating on simulation algorithms and on control and communication technologies
• Investigation of wind power integration potential to the Greek interconnected power system and development of grid code recommendations
• Application of pumped storage to increase wind penetration levels in isolated island grids
• Investigation of PV penetration potential in isolated island grids • Technical issues and feasibility studies for the interconnection of isolated island grids to the mainland power system
• Advanced short-term wind power forecasting functions for operational planning, using numerical weather predictions and advanced artificial intelligence techniques
• Power quality analysis of wind turbines and wind farms, with a particular emphasis on harmonic emissions
• Design of electrical generators and converters for small wind turbine applications, with a particular focus on permanent magnet synchronous generators
• Research on small stand-alone systems fed by renewable energy sources, including the design of the electrical and control systems for completely autonomous wind-driven desalination systems
• Development of laboratory infrastructure for renewable and distributed energy systems and participation in relevant laboratory and pre-standardization activity networks.
Since 1990, the Applied Mechanics Section of the Department of Mechanical Engineering and Aeronautics, University of Patras (UP), has focused on educational and R&D activities involving composite materials and structures. Emphasis is given to anisotropic material property characterization, structural design, and dynamics of composite rotor blades of wind turbines.
Experience has been acquired by participating in several national and EC-funded research projects. UP is the Task Group leader in the EC-funded research project OPTIMAT BLADES, an investigation of blade material behavior under complex stress states that assesses the effect of multi-axial static and cyclic loading on strength and life of composite laminates. Results are available in the form of design guidelines for rotor blade manufacturers, among others.
Other research activities of the Applied Mechanics Section include: (a) development of finite element formulations and dedicated code accounting for selective nonlinear lamina behavior (e.g. in shear, in the laminate) to model property degradation due to damage accumulation and predict the life of large rotor blades under spectrum loading; (b) probabilistic methods in the design of composite structures; (c) residual strength and fatigue damage characterization of composite materials using wave propagation techniques; (d) smart composites and structures; and (e) structural damping and passive and active vibration control.
Participation in IEA Wind tasks
Greece participates in Tasks 11 and 20. Task 11, Base Technology Information Exchange, promotes wind turbine technology understanding through cooperative activities and information exchange on R&D topics of common interest among member countries.
Extra emphasis has been given through the years, especially at NTUA and CRES, to the development of aerodynamic models of wind turbines, an activity that is supported by the involvement in the activities of Task 20, HAWT Aerodynamics and Models from Wind Tunnel Measurements.
The Next Term
In 2005, the existing legal framework was reviewed, and in mid-2006 a new law for the promotion of renewable energy sources and especially wind energy took effect. The new law aims to accelerate licensing procedures and alleviate major bureaucratic bottlenecks. A critical point for the achievement of the targets is completion of the extensive projects destined to boost transmission capacity of the grids in the areas of great interest for wind energy deployment (Eastern Macedonia–Thrace, Southeastern Peloponnese, and Euboea).
The promotion of national land planning currently under way is expected to further facilitate investments in renewable energy systems. However, reaching the targets set for 2010 is still uncertain, unless additional measures and policies are undertaken, both institutional and technological. The institutional measures are expected to be implemented in the new legal framework, while technological actions such as the interconnection of the Northeastern Cyclades islands complex with the interconnected system are still to be decided and implemented.
(1) 4th National Report Regarding the Penetration Level of Renewable Energy Sources Up to Year 2010 (October 2007).
Authors: Kyriakos Rossis and Eftihia Tzen; CRES, Greece.