Middle East Technical University1
Introduction As a country highly dependent on foreign fossil fuel sources, Turkey experiences many problems due to its increasing energy consumption. To reduce vulnerability to disruptions in natural gas and to maintain economic and sustainable development, domestic and renewable energy resources need to be developed. Major renewable energy sources of Turkey are hydropower, solar, wind, geothermal and biomass energies. Table 1 shows reserves of renewable energy sources in Turkey and their associated shares in the electricity generation in 2011. As can be seen from Table 1, hydropower has the largest share in electricity generation and recently private sector investments for hydropower plants have increased. However, increase in the contributionof hydraulic energy to electricity generation brought some social and environmental problems with it. Thus, other potential renewable energy sources need to be evaluated to increase their contribution to electricity generation in Turkey as well in shaping energy policy of the country.
Table 1. Reserves and electricity generations from renewable energy sources * EUAS (2012) + DSI (2013) ** MENR (2012) (geothermal only for electricity)
Methods/Materials In this study, prioritization of the development of renewable energy sources, namely hydropower, solar, wind, geothermal and biomass, to increase their contribution to electricity generation of Turkey is investigated using the Analytic Hierarchy Process. Renewable energy sources are assessed using two main criteria, Energy Goals and Environmental Goals. Based on a comprehensive literature review, Energy Goals are evaluated in terms of (i) maintaining security for electricity supply, (ii) supplying electricity with low prices, (iii) maintaining stability for electricity generation, and (iv) maintaining economic development. On the other hand, Environmental Goals are evaluated with respect to (i) maintaining low carbon, SOx, and NOx emission, (ii) maintaining environmental sustainability, (iii) minimum impact on public health, and (iv) maintaining social acceptability.
In order to evaluate major renewable energy sources of Turkey, a survey was prepared based on a detailed literature review. To be able to complete the survey, the participant has to have background knowledge on all of these renewable energy sources and all energy and environmental sub-criteria. Participants were selected based on their experience and previous work on renewable energy sources, technologies, market conditions, and policies. Initially, colleagues working on renewable energy resources and personnel from appropriate departments of government bodies are contacted. The survey forms were sent to a total of 120 participants. Only 37 completed surveys were received and evaluated using AHP.
Results and Discussion Overall priorities obtained as a result of this study is given in Figure 1. Hydropower is selected as the most preferred renewable energy source followed by solar and wind energies to increase their contribution to electricity generation in Turkey. On the other hand Hydropower performed poorly interms of satisfying Environmental Goals especially for "maintaining social acceptability" and "Maintaining Environmental Sustainability". Current situation in Turkey supports the results of this study. To satisfy energy goals, in the past decade, a number of laws (i.e. Electricity Market Law, Law on Utilization of Renewable Energy Resources for the Purpose of Generating Electrical Energy) encouraging the development of renewable energy resources for electricity generation were passed and licenses were granted for thousands of small hydropower plants (SHPP). Despite all the legislation and government action such as provision of incentives, energy goals still remain unattainable due mainly to public resistance to SHPPs. Local people, not included in and informed about these projects as stakeholders, have taken many such projects to court and had motions granted for stays of execution. In order for the government policy of increasing the share of renewable sources in electricity generation to be successful, the social and environmental impact of new projects needs to be evaluated with the participation of all stakeholders.
Conclusions In this study, the major renewable energy sources of Turkey (i.e. solar energy, biomass energy, geothermal energy, wind energy, and hydropower) are evaluated for electricity generation and the following conclusions are reached: * Within the Energy Goals criterion, "Maintaining Security for Electricity Supply" (0.359) is considered to be the most important sub-criterion due to existing economic and political problems Turkey faces. Hydropower is identified as the renewable energy source that best satisfies this sub-criterion. * Within the Environmental Goals criterion, all four sub-criteria received approximately equal priorities. "Minimum Impact on Public Health" (0.290) is considered to be a little more important than the others. Solar energy is identified as the renewable energy source that best serves this sub-criterion. * Overall, hydropower is prioritized as the most preferred renewable energy resource to increase its contribution to electricity generation of Turkey. However, hydropower performed poorly in satisfying the "Maintaining Environmental Sustainability" and the "Maintaining Social Acceptability" sub-criteria. EUAS (Electricity Generation Company) (2012) 2011 Annual Report. Electricity Generation Company. Retrieved September 4, 2013, from EUAS: http://www.euas.gov.tr
DSI (State Hydraulic Works) (2013) Water and DSÃÂ°. Ministry of Forestry and Water Affairs, General Directorate of State Hydraulic Works.
MENR (Ministry of Energy and Natural Resources) (2012) Enerji ve Tabii Kaynaklar BakanlÃÂ±ÃÂÃÂ±. Enerji ve Tabii Kaynaklar BakanlÃÂ±ÃÂÃÂ± ile BaÃÂlÃÂ± ve ÃÂ°lgili KuruluÃ
ÂlarÃÂ±nÃÂ±n AmaÃÂ§ ve Faaliyetleri. BaÃÂlÃÂ± ve ÃÂ°lgili KuruluÃ
Âlar Dairesi BaÃ
ÂkanlÃÂ±ÃÂÃÂ±, Ankara (in Turkish).