The Gorna Arda hydro power project is an under construction hydro power project the upper stream of the river Arda

Arda River (Maritsa)

The Arda is a river whose source lies in the Bulgarian Rhodope Mountains near the town of Smolyan, flowing 290 kilometres eastward past Kardzhali and Ivaylovgrad and through Greece in the northern portion of the Evros prefecture including Kastanies. It then enters the Maritsa just west of Edirne,...

, southern Bulgaria

Bulgaria

Bulgaria , officially the Republic of Bulgaria , is a parliamentary democracy within a unitary constitutional republic in Southeast Europe. The country borders Romania to the north, Serbia and Macedonia to the west, Greece and Turkey to the south, as well as the Black Sea to the east...

. The project consists of Madan, Ardino and Surnica hydro power stations with a nominal output of 174.2 MW. The Surnica hydropower station will have two turbine

Turbine

A turbine is a rotary engine that extracts energy from a fluid flow and converts it into useful work.The simplest turbines have one moving part, a rotor assembly, which is a shaft or drum with blades attached. Moving fluid acts on the blades, or the blades react to the flow, so that they move and...

s with a total nominal output of around 62 MW of power.

The project is developed by HEC Gorna Arda consisting of NEK EAD

NEK EAD

Natsionalna Elektricheska Kompania NEK is the Bulgarian national electricity distributing company also being the second largest company in Bulgaria...

 (70%), and a consortium of Austrian companies EVN Bulgaria

EVN Group

EVN Group is an Austrian-based producer and transporter of electricity, one of the largest in Europe having over three million customers in 14 countries. The company also operates in water treatment, natural gas supply and waste management business areas...

 and Alpine Bau (30%). The project is estimated to cost €500 million.