Hydroelectricity in Turkey
Hydroelectricity is a major source of electricity in Turkey. The main river basins are the Euphrates and the Tigris. Many dams have been built and hydroelectricity makes up about 30% of the country's electricity generating capacity. Generation can vary greatly from one year to the next depending on rainfall.[lower-alpha 1] In good years, substantial amounts of hydroelectric power can be generated due to Turkey's mountainous landscape and abundance of rivers. Government policies have generally supported dam construction. Some dams are controversial with neighbouring countries, while others face concerns about damage to the environment and wildlife of Turkey.[2]

56 TWh of hydroelectricity was generated in 2021, which was 17% of Turkey's total electricity,[3] from 31 GW of capacity.[4] According to analysts at S&P Global, when there is drought in Turkey during the peak electricity demand month of August, the aim of the State Hydraulic Works to conserve water for irrigation can conflict with the Turkish Electricity Transmission Corporation's goal of generating electricity.[5] Although Turkey's energy strategy may change in the future due to climate change causing more frequent droughts,[6] hydropower is predicted to remain important for load balancing of solar and wind power.[7]: 72 Converting existing dams to pumped storage has been suggested as more suitable than building new pumped storage.[8]
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Water resources
Turkey's average annual precipitation from 1979 to 2019 was slightly over 50 cm and average temperature around 15 °C; but climate change reduces rainfall and makes it less regular, and hydropower falls in proportion to the rainfall.[9] During that period annual precipitation fluctuated over 60 cm and under 45 cm,[9] and average annual temperature varied by 4 degrees.[9] The highest precipitation is in the Eastern Black Sea Region.[9]
Turkey is already a water stressed country, because the amount of water per person is about 1,500 m³ a year: and due to population increase and climate change it is highly likely the country will be water scarce (less than 1,000 m³) by the 2070s.[10] Little change is forecast for water resources in the northern river basins, but a substantial reduction in the southern river basins.[10] Konya in central Turkey is also vulnerable.[11]Hydroelectric potential
In 2021 hydropower was the cheapest source of electricity in Turkey,[5] but the IEA expected only a little hydropower to be constructed by 2026, partly due to the competitive prices of wind and solar.[12]: 62, 63 Some academics, such as those at Shura Energy Transition Center, say that there is limited potential for more hydropower.[13]In 2022, Turkey's Energy Ministry stated that there is "hydroelectricity potential of 433 billion kWh, while the technically usable potential is 216 billion kWh, and the economic hydroelectricity potential is 160 billion kWh/year;"[14] for comparison, 56 billion kWh was generated in 2021.
Reduced precipitation is forecast due to climate change in the Tigris and Euphrates river basins, like the 2020 drought,[15][16][17] which caused a generation drop of over 10% compared to the previous year.[18] In 2021 generation by non-hydro renewables overtook hydro for the first time, partly due to the drought,[19] To conserve hydropower, solar power is being added next to existing hydropower,[20] as at Lower Kaleköy.[21] Adding hydropower to existing irrigation dams may also be feasible.[22]
Energy storage and dispatchability
Hydropower usually peaks in April or May.[23] Adding pumps to existing dams, so water could be pumped back up to store wind and solar electricity, has been suggested as more feasible than building new dams with pumps.[24] Although dammed hydro can be dispatched within 3 to 5 minutes,[25] according to analysts S & P Global such generation instructions from the Turkish Electricity Transmission Corporation can be countermanded by the State Hydraulic Works, which may have contributed to blackouts in August 2021.[26]
History

The first power plant of any kind in Turkey was a 60 kW hydro plant constructed in Tarsus, which started operation in 1902.[27] Feasibility studies for more dams were done in the 1920s and 1930s.[28] After the State Hydraulic Works (DSI) was established in 1954, major projects (such as the first large dams, the Seyhan Dam and Sarıyar Dam)[28] were better funded and significant quantities of hydroelectricity were generated for the first time.[29] Turkey built dams to meet its growing energy demand with rapid urbanization, industrialization, and population growth.[28] Between 1970 and 2019 generation increased at almost 10% per year,[30] and 2.5 GW was added during 2020.[4] In 2021 generation from other renewables exceeded hydro for the first year ever.[19]
Following the 1973 oil crisis, the government began the Southeastern Anatolia Project, both for energy security and to try and help the poorersoutheastern part of Anatolia catch up with the growing economy.[28] Amongst other development, such as irrigation projects, several hydropower plants were built.[31] By 1988 hydropower was over 60% of total electrical generation. Before that coal had been the only other substantial source. Natural gas also began to play an important role around the same time. [19] The Southeastern Anatolia project cost 190.8 billion lira (US$ 34 billion, at 2020 prices).[32] According to the Istanbul Chamber of Commerce, this was paid back by 2021 by the value of the electricity alone.[31] Almost 25% of the country’s hydroelectricity is produced by the project.[28][33]
However, some Kurds have called the project “mass cultural destruction”.[28] Most of the project has been completed, but at least one dam (Silvan Dam) and hydroelectric power plant are still under construction.[34] The project is controversial with the downstream countries of Iraq and Syria.[35] According to academic Dr. Arda Bilgen, the reduced flow of the Euphrates was one reason why Syria supported PKK attacks on Turkey in the 1980s.[28] Since the Syrian Civil War started in 2011 international water cooperation has been very difficult.[28]
Since the beginning of the 21st century private companies have been able to get long leases on rivers,[36] and DSI has mainly coordinated and supervised rather than constructing its own power plants.[28] Particularly in the north-east of Turkey, small scale projects were developed. Contrary to expectations, these did not bring about more consensus and local acceptance than large dams.[36]
Projects
The geography of Turkey includes 25 river basins, and generally those with the most potential for hydropower are the least populated.[36] The private sector has generally invested in run-of-river hydroelectricity, and the public sector in dammed hydro.[36] Private sector water use agreements are usually for 49 years, with minimum discharge flow 10% of the previous ten-year average.[36] There are over 700 hydropower plants, making up 31 GW of the country's 100 GW generating capacity.[27] The state electricity company owns 14 GW, while the only private companies with over 1 GW are Cengiz, EnerjiSA and Limak.[27] In spring water flow is greatest but electricity demand is low, so the electricity price may also be low.[36] Another 4 GW is planned for after 2023.[36]
The province with the most hydroelectricity capacity is Şanliurfa with over 3 GW, followed by Elazığ and Diyarbakır each with over 2 GW.[27] The highest dam is Yusufeli.[37]

Largest power stations
The three longest rivers in Turkey also have the highest capacity hydropower plants, the largest being Atatürk Dam on the Euphrates. On the same river are the second and third largest. Ilısu on the Tigris is the newest large dam. In contrast the Kızılırmak River, which flows north into the Black Sea, has smaller projects. Its hydro plants are less than 1 GW, the largest being Altınkaya.[38]
Impacts on people and the environment
There have been both positive and negative environmental effects caused by the dams and hydroelectric power plants. One of the most useful features of dammed hydroelectric power plants is that generation can be quickly ramped up and down, to meet demand and balance wind and solar. Compared to fossil fuel power plants, the country's hydroelectricity emits much less greenhouse gas. Being a local source it improves the balance of payments, since Turkey imports around three-quarters of its energy.[39]
As well as environmental impact assessment reports before construction there are also water-usage studies and ecological evaluation: but according to a 2021 study by Melis Terzi, stipulations in the reports are sometimes ignored during construction.[36]: 74 The study also says that the legal requirement to provide fish passages has often been ignored.[36] Large hydropower may be bad for sturgeon, as in neighbouring Georgia.[40] In 2021 the Turkish company contracted to build Namakhvani hydropower plant in Georgia pulled out after protests.[41] According to the Bianet newspaper, sometimes small rivers have completely dried out in summer due to hydropower.[42] Fish, such as the kisslip himri, may be threatened with extinction, but this is unclear as no studies have been published since 2014.[43] Sediment management is sometimes not up to the EU Water Framework Directive standard.[44] Turkey has not yet adopted the sustainability certification devised by the International Hydropower Association in 2021.[45]
In some areas locals are concerned that dams decrease nature tourism.[36] Like national energy policy as a whole,[46] decision making for dam construction is centralized and not always transparent, which can lead to complaints by local people.[36] Tens of thousands of people have been displaced by reservoirs.[47] Archaeologists, such as Nevin Soyukaya, say that there has been disregard of the damage to ancient settlements, such as at Hasankeyf.[48]
Dams on international rivers, such as the controversial Ilısu Dam on the Tigris completed in 2021, can cause water shortages in downstream countries; to wit, Iraq and Syria.[49][35] Although international protests stopped foreign funding of the dam, Iraqi protests could not prevent it being built with domestic funding.[50] There are also 14 Turkish dams on the Euphrates.[35] The Tigris and Euphrates are the main source of water for much of Iraq, and Iraqi academics say that Turkish dams on those rivers are damaging the environment of Iraq.[35] Although a Euphrates water sharing agreement was made in 1987 (500 cubic metres per second leaving Turkey[51]) this assumed the water flow would not reduce. However, natural flow has been reduced due to climate change in Turkey, leading to real flow being less than Iraq's allocations in the agreement.[52] Hydropower projects on the transboundary rivers Kura and Aras have been criticised by local environmental activists and have also caused tensions between Turkey and downstream Caucasian countries, such as Azerbaijan.[53]
Economics
As of February 2022 the feed-in tariff (FiT - excluding domestic components incentive) was 400 lira/MWh (about 29 USD), more than solar and wind but less than geothermal.[54] However in late 2021 the government and private sector energy analysts had already predicted that the day ahead price on the electricity market throughout 2022 would be higher than the FiT for the first year ever, thus resulting in a negative contract for difference.[54] By late March 2022 the spot price of electricity had reached the ceiling (thrice the average price over the past 12 months) of 1745 TL (over 115 USD),[55] and the Energy Ministry was reported to be considering different ceiling prices for different sources of electricity.[56] It is not yet known what the ceiling price of hydroelectricity would be, or even if such a scheme will actually be legislated. Because transmission congestion of run-of-river can cause price imbalances, zonal pricing has been proposed.[57]
Politics
Many dams were built by Republican People's Party governments in the 20th century. The party's current stance on hydropower is unclear however, as its 2018 general election manifesto included no mention of it and the party has opposed many recent dam projects, mostly due to environmental concerns.[58] The Justice and Development Party, which has been in power nationwide since 2002 (in coalition with the Nationalist Movement Party since 2016), has also built many dams and encouraged private companies to build run-of-river hydro. According to its party platform, the Good Party "supports the utilization of local and renewable resources to their fullest extent", which includes hydropower.[59] The Peoples' Democratic Party, in contrast, is more opposed to hydroelectric plants due to their impact on communities and environments.[60] Arda Bilgen, a Turkish academic, says that since the 1960s, the central government (inspired primarily by the United States Bureau of Reclamation) has used dam building to strengthen the central government's hold over Eastern and Southeastern Anatolia and to help grow these regions' economies with a top-down approach.[28]
Turkey was one of three countries which voted against the 1997 UN Watercourses Convention, which is the main international freshwater law. According to Nareg Kuyumjian at the Environmental Law Institute this was because Turkey benefited from "hydroanarchy".[53]
Notes
- For example, drought in 2020 caused a generation drop of over 10% compared to the previous year.[1]
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