Five new hydropower plants in the Turkish Marmara region have recently been equipped by Upper Austrian-based all-round hydropower specialist WWS Wasserkraft GmbH.

All five facilities were incorporated into the extensive water supply system of Adapazarı, the capital of the Sakarya province. These water resources had not been utilised for hydropower generation before. In addition to seven powerful turbines, WWS also delivered the corresponding generators by Hitzinger of Linz, Austria, which has a long-standing tradition as a trusted manufacturer. All the facilities have been up and running in the western Anatolian province since October 2020.

Adapazarı has a reputation as one of Turkey’s fastest growing and economically prosperous cities. Its population has increased almost tenfold over the past 70 years. Today the Sakarya province’s capital has around 270,000 inhabitants. Its location is quite favourable, allowing its population to profit from the proximity to Istanbul’s large sales markets and the ports of Izmit. The region’s principal economic drivers are its textile industry, industrial suppliers, and service providers.
Adapazarı draws its freshwater from the Akçay, a tributary to the Sakarya river, to which the province owes its name. “Quite a few years ago the national organisation ­SASKI, together with the provincial public utility operator, decided to construct  a dam on the Akçay river to provide freshwater to the local population of Sakarya,” says Günther Scharrer, Sales Manager at WWS. The dam’s construction was completed in 2016. Today, around 10 million cubic metres of ­water are stored behind the 55 m dam wall. Apart from providing drinking water to the city, the reservoir is also used for irrigating the surrounding farmland.

From the dam to the city
A 27 km pipeline carries the water from the Akçay dam to Adapazarı. Originally, this arrangement was not designed to create renew­able energy while supplying Sakarya with water – a fact that municipal public utility operator Akim Enerji Inc Co. was hoping to change. In implementing their plan the oper­ators relied primarily on knowledge and technology ‘made in Austria’: the contract was awarded to Upper Austrian hydropower specialist WWS Wasserkraft GmbH, which is headquartered in Neufelden in the district of Rohrbach. In total, WWS was to provide 7 turbines for four power houses across five projects, which Günther Scharrer describes as follows: “The water from the Akçay dam is fed to the turbines in Ikramiye and then flows to Hacimercan, where the next set of machine units are located. Hacimercan is also home to another facility: Balikci, which has its water supplied from a different river. From there the water flows straight through the city of Adapazarı and on to the Hizirilyas power house, which also contains two machine combinations. Then there is hydropower plant Keremali, which has its water supplied from an independent source via an existing penstock instead of a pressure reducing valve.”

Pelton technology for 78 bars of pressure
As a result, the five facilities are arranged as follows: Hydropower plant Ikramiye was fitted with a 3-nozzle Pelton turbine at the end of a 9.4 km penstock. The turbine is designed for a net head of 390 m and a design flow rate of 1.2 m3/s, with a generating capacity of 4,140 kW. In Hacimercan two structurally identical vertical 6-nozzle Pelton turbines were installed, each designed for a 260 m head and a design flow rate of 1.25 m3/s. The facility has a maximum bottleneck capacity of 2,868 kW. Hydropower Plant Balikci, which was integrated into the same power house, uses a Francis spiral turbine designed for a head of 49.27 m and a flow capacity of 0.5 m3/s. Its generating capacity amounts to 220 kW. Hydropower plant Hizirilyas houses two Francis spiral turbines, each designed for a nominal head of 84.34 m and a design flow rate of 1.25 m3/s. With water supplied via a 12 km penstock, the twin arrangement achieves a bottleneck capacity of 967 kW. In addition, hydropower plant Keremali had a single-­jet Pelton turbine installed. Although this was designed for a flow capacity of only 75 l/s, it utilises a net head of 779 m. “Keremali was certainly the most technically challenging powerplant of all units supplied. The combination of 78 bars of pressure and a very low flow rate proved quite a challenge for our design engineers,” says Scharrer. In the end, these ambient conditions resulted in a rugged, compact turbine design with small Pelton runner buckets. “This turbine is the result of decades of experience provided by our Head of Technology, Josef Wögerbauer and the expert knowledge contributed by scientists from the University of Technology in Graz.” The operators were instantly impressed with the quality and performance of this turbine and also the six other units.

Custom-built generators
“Our project references and many recommendations from satisfied customers, as well as the high quality provided by our premium subcontractors – especially Hitzinger – fully convinced our customers at Akim Enerji Inc. Co. that our solution was the right choice“, says a happy Günther Scharrer. For the experienced generator manufacturers from Linz, a city famous for its steel industry, this contract was very special. “We have often delivered turbines to Turkish customers in the past. But WWS’s contract for the seven generators in the Marmara region has opened up a whole new dimension,” says Volker Schmid, who works for Hitzinger. To prove his point, he mentions the different capacities and constructional designs of the generators, each of which was precision-designed to meet the respective requirements. Every single order for a Hitzinger turbine is pre-checked thoroughly to determine which aspect to focus on: overall ruggedness or high-end efficiency. As a result, the machines provided by the Linz-based high-end manufacturer are all designed and constructed on an individual basis. Relevant factors range from the design of the magnetic properties to the copper-to-iron ratio, the insulation system and many others. Based on decades of knowledge and in-house research, Hitzinger is able to provide hydropower generators with highly stable rotational speeds and a powerful performance profile, combined with an extremely long life cycle. For the operators of the new Sakarya hydropower plants these were the decisive factors in choosing the powerful machine units from Upper Austria. “It was important for our customers that our overall package should be manufactured in-house as much as possible. Both the turbines and the generators are manufactured in Austria,” says Scharrer.  As he points out, the competent, straightforward after-sales support is especially appreciated both by the turbine manufacturers themselves and the plant operators.

By-pass ensures water supply
Like drinking water power plants in our parts of the world, each of the hydropower plants is equipped with a by-pass system. This ensures the sustained supply of freshwater even in case of a power failure. Currently 100% of the power generated by the plants is fed into the public grid. Additionally, a stand-alone solution is to be implemented in the near future as a precaution to sustain the water pumping operation in an emergency.

A developmental milestone
In 2017 the Upper Austrian hydropower specialist was awarded the contract for supplying the plant equipment. WWS’s engineers were able to commence construction in late 2019. “The transport and installation work carried out by our staff was more or less business as usual. We had been able to clear away possible problems and pitfalls in advance, based on our extensive experience in the Turkish market On top of that, the great collaboration and open communication with our customers allowed us to implement even some extra requirements. The construction of the Akçay dam had been delayed, so we had to move our schedule back a little, but that didn’t cause any problems,” says project leader Lukas Wögerbauer jr. Even the restrictions and obstacles due to the coronavirus pandemic couldn’t delay the project. “Our team had to undergo a lot of PCR testing, but that didn’t affect our workflow at all.”
Since the completion of the start-up phase in October 2020 all seven machine units have been up and running perfectly, proving their worth in everyday operation. The significance of the project for the city of Adapazarı and the entire province of Sakarya can hardly be overstated. Also, the hydroelectric utilisation of the water supply system marks an important mile­stone in the development of the region’s infrastructures. What is more, the seven machine units provide around 45 GWh of clean energy to the public grid. Best of all, it is proven Austrian hydropower technology that will make sure of that for many years and decades to come.