Astrit BARDHI Myrteza BRANESHI Thomaq KOBLARA Marjola PUKA 8th International Scientific Conference Energy and Climate Change Athens, 7-9 October 2015 Problems encountered in Albanian power system by connection of new power generation units Astrit BARDHI Myrteza BRANESHI Thomaq KOBLARA Marjola PUKA

In this paper we have study the impact of small hydropower plants in power quality of connection at power system in order to analysis the reasons that caused these anomalies and to find of the ways to overcome them.

CONTENTS A brief historical development of Small Hydropower Plants in Albania Problems encountered by connection of new power generation units Analysis a part of distribution network. Conclusions

A BRIEF HISTORICAL DEVELOPMENT OF GENERATION UNITS IN ALBANIA Over 90% of Albanian electricity is produced by hydro power plants The main hydropower plants are Ulza and Shkopeti with 25,6 MW and 24 MW capacities built along Mat river, Koman, Fierza and Vau i Dejes built along Drini river with 600 MW, 500 MW and 250 MW capacities . Also, some thermal electricity generation units were built, but during the last two decades they are out of service. Until the end of 90’ of the last century were built many SHPs, especially in rural area.

A brief historical development of Shps in Albania The power capacity of SHPs was around 10% of total unit’s generation in Albania in the end of 90’. The capacity of SHPs is between 100 to 400 kW. The most of SHPs built before 90’, due to their amortization are out of service. This situation continued until 2000’. During these years no new hydropower plants have been built.

Situation of shps before 2000’

Situation of shps before 2000’

Situation of shps before 2000’

A brief historical development of SHPs in Albania After 2000, the privatisation schemas in energy production, tranmission and distribution network have started. During the last years the interest of private investitors concerning to SHPs is increased. Around 80 concessionary contracts for construction of SHPs have been approved. The total capacity of SHPs is around 400 MW with annual energy production of 1,827 GWh.

SMALL HYDRO POWER PLANTS IN ALBANIA

OUR CASE OF SHP CONNECTION AT DISTRIBUTION SYSTEM

OUR CASE OF SHP CONNECTION AT DISTRIBUTION SYSTEM Generation units

ANOTHER CASES OF SHP CONNECTIONS AT DISTRIBUTION SYSTEM Generation units Generation units

ANOTHER CASE OF SHP CONNECTION AT DISTRIBUTION SYSTEM Generation units

SMALL HYDROPOWER PLANTS IN ALBANIA 2011 2012 2013 2014 June-2015 35 kV 8 16 18 23 24 10 kV 38 43 50 55 6 kV 6 10 11 Total 52 62 71 84 90

Energy Annual Production of SHPs connection at 35 kV Regional Energy Annual Production 2011 2012 2013 2014 kWh Tirane 35,518,610 Fier 31,042,291 33,438,444 50,136,750 45,688,475 Gjirok. 29,962550 59,851,102 53,023,582 28,189,924 Berat 10,644,869 23,413,459 29,280,293 30,667,730 Elbasan 22,575,251 46,404,599 53,459,932 43,352,289 Korçe 8,642,718 17,834,463 25,475,072 34,644,855 Kukes 15,114,050 14,784,140 Burrel 16,419,400 34,869,620 54,333,089 39,553,260 Total 154,805,689 246,519,077 309,488,032 300,390,466

ENERGY ANNUAL PRODUCTION OF SHPs CONNECTION AT 6, 10, 20 KV Regional Energy Annual Production 2011 2012 2013 2014 kWh Tirane 13,150,988 Gjirok. 1,635,440 5,254,670 5,271,660 8,097,650 Berat 1,518,849 2,608,956 2,702,816 2,256,556 Elbasan 11,487,467 13,943,270 17,072,578 15,669,348 Korçe 17,465,319 15,855,486 19,206,944 20,868,914 Kukes 7,330,450 10,009,118 24,520,317 46,839,194 Burrel 5,838,650 8,772,599 15,276,894 19,382,382 Total 50,020,847 61,957,891 92,331,608 136,927,986

Progress of small hydropower development in Albania year Kesh Gen SHPs Coefficient of Small/Ekesh gen Installed power Annual production Number of small hydropower plant plants Power by SHP/ power by other power stations kW MWh pieces % 2006 1,431,000 5,516,000 27 26.017 1.82 61,918 1.12 2007 2,933,000 33 27,454 1.92 59,177 2.02 2008 3,770,000 34 27,759 1.94 62,025 1.65 2009 5,201,000 35 28,009 1.96 89,306 1.72 2010 7,555,000 43 53,194 3.72 159,040 2.11 2011 1,350,000 3,899,477 53 77,854 5.77 136,831 3.51 2012 4,027,012 69 142,104 10.53 290,998 7.23 2013 5,811,762 90 226,004 16.74 548,148 9.43 2014 6,895,452 94 240,100 18.23 657,453 11.3

Voltage nodes with shps, the worst scenario. Nominal Voltage [kV] Value of node voltage [%] System_110 kV 110 100 B10kV_Bogove 10 11.83 118 B10kV_Çorovode 12.73 127 B110kV_Uznove 110.44 B20kV_Uznove 20 20.07 B_110kV_Berat B35kV_Bogove 35 41,42 B35kV_Çorovode 44.58 B35kV_FQ1 45.01 126 B35kV_FQ2 44.96 B35kV_Poliçan 39.78 113 B35kV_Uznove 35.79 102 B6kV_Poliçan 6 6.81 B6kV_Uznove 6.07 101

IMPACT OF SMALL HYDROPOWER PLANTS ON VOLTAGE LEVEL IN REGIONAL POWER SYSTEM

PROBLEMS APPEARED IN POWER SYSTEM BY SHPs These energy recourses are built on rural area, where the distribution system is a radial form. At rural electric power system, no investments were done in recent years. In some cases, the energy production by SHPs is not supported by the power transformers of substations. The transmission lines are overloaded, which can cause the interruption of the supply with electricity of consumers.

PROBLEMS APPEARED IN POWER SYSTEM BY SHPs Another problem encountered is that the voltage values in some power system nodes are upper than nominal or allowed value. The private investirors are not interested about capacities of existing transmission lines or substations at regional distribution system. Development of SHPs is realised in the indepedent form and it is not in good acordance with investments of Distribution System Operator. Often, the new small hydropower plants, due to limited transmission lines capacities of distribution system, operate under their capacities.

Recommendations To improve voltage levels in the system, the first thing that we recommend is the change of the configuration of the system, from a radial network to a ring network. Improvement of contracts of private operators with Albanian Power Corporation, in which small producers of electricity to give in or take from reactive power. In the power system the installed new transformers must be with automatic on load tap charger. To establish a Dispaching Center in order to monitor and analysis on line the power parameters as active and reactive power production, nodes voltage level, frequency etc.

Thank You