Albania’s per capita hydro potential is one of the largest in Europe. Professor Luan Trola* explains how it is being exploited.
The geomorphology of Albania is extremely favourable to hydropower development. Of the 28,748km2 that constitutes Albanian territory, around 75% is characterised by broken-relief moun-tainous and hilly terrain. The remaining 25% of plains area is situated mainly in the coastal zone, in the western part of the country. As a whole, the country averages 700-730m asl. The rivers and their branches have their sources in high regions – in most cases more than 1000m asl, so there is potential to exploit their energy for a fall of at least 900m.
Albania is one of those Mediterranean countries that has plentiful rain. Rainfall over the whole territory is around 1450mm/year, but distribution within the country varies widely. Average precipitation varies between 600mm and 3500mm, depending on the geographical position. Seasonal distribution is equally uneven, as the summer months are very hot and dry: around 85% of the precipitation occurs during the period November-May and only 15% during the rest of the year.
Albania has a hydro network consisting of seven main rivers, with plenty of secondary and tertiary branches. Together, flow from the major rivers into the sea has an average volume of around 40 million m3, which corresponds to an average flow of 1300m3/s.
Expressed another way, the annual hydro potential of the country is around 12,000m3 per capita.
Albania’s stock of water riches is therefore considerable, and offers enormous potential for production of hydro power.
The routes of Albania’s main rivers are shown in the map right, and their main characteristics are given in Table 1, below.
The hydrotechnical potential of Albania was considered for the first time in a paper by Giuseppe Salvini in the journal L’energia Elettrica in 1941 under the title Contribution on the study about the hydroelectrical possibility in Albania. Studies for schemes to exploit the hydrotechnical potential of some of the main Albanian rivers were later carried out by Gidroenergoprojekt, the Russian state consulting company.
The results of these two studies did not bring projects very much closer to being realised, for simple reasons. At the time the early studies were carried out there was little in the way of long term hydrological, topographical, and geology-engineering data; the necessary equipment was not available; roads did not exist to serve many of the sites. In addition, at the time the studies were prepared highly qualified personnel were in very short supply. As a result, the studies were of very limited quality. Now, their value is mainly historical.
In later years, Albanian specialised institutions undertook a number of studies, with the aim of designing hydroelectric schemes on the major rivers and their main branches. The organisations carrying out the studies were: the Institute for Studying and Designing Hydro Power Stations; the Civil Engineering Faculty; and the Bureau for Designing Communal Works, at the Ministry of Communal Economy. The Institution of Hydrometeorology, the Geological & Mining Faculty and the Geodesi-Geology Institute have given valuable help to support these studies.
Hydro potential and realisation
The studies, based on appropriate topographical, hydrological and geological data, and on a great number of complex field surveys, have been the basis for designing the hydro power stations currently operating in Albania. As well as evidencing the total theoretical and technical energy potential, the studies considered the distribution of energy along the rivers, and made recommendations about technical solutions, including giving some of the principal parameters for each hydro power station.
Certainly those studies need to be improved, in both their quantitative aspect (additional hydrological, topographical and geological information which has been obtained during recent years must be taken into account) and in their qualitative aspect, extending the studies to all the water resources of the country.
Finally, a further requirement that would modernise the studies from an economic, social and environmental level, is to convert the technical potential given in the study to a set of economic priorities.
The results of all the studies undertaken by Albanian organisations are given briefly in Table 2. As can be seen, the potential annual overall hydro energy is almost 15TWh, of which the Drin river (Black Drin and White Drin), the biggest water artery of the country, offers 51.3% and the Vjosa river, the second largest river in Albania, offers 12.7%. The remaining 36% is distributed between all the country’s other rivers. On a per capita basis the exploitable potential (referring to the population census of 1990), is 4608kWh per capita per year. Comparing this result with similar data on other European countries shows that Albania is among the richest countries as regards hydroelectric potential.
There are several hydro power stations already operating in Albania, which together exploit around 36% – 54000GWh – of the potential hydro power. The main parameters of the operating stations are listed in Table 3.
If the full hydro potential of the country were to be exploited, studies have shown that 80 new hydro power stations would be required. Of these l9% would be of dam type, 25.5% of a combined type (dam + derivation channel), and 55.7% wold be of an open channel type. According to icold criteria, all the dams enter into the high dams category.
Micro hydro power stations could be installed in addition to these large dams. At this time, there is already a considerable number of micro hydro power stations functioning in Albania. Their annual production capacity is around 50 GWh.
Prospects for additional micro hydro power stations are currently more favourable than those for large dams because of the low investment required for micro projects, and the fact that it is not necessary to deal with the social problems such as resettlement that arise in the case of large dam projects. The most likely projects at present involve the rehabilitation and restructuring of existing micro hydro power stations and the construction of others in that category.
There is a medium-voltage power transmission grid functioning in Albania. This makes possible electricity distribution and supply to domestic consumers, as well as interconnection with neighbouring countries for export and exchange of energy. The total length of transmission lines is currently 3550km, of which 1150km is at a tension of 35kV, 1180km is at 110 kV, and 1110km is at 220kV.
The large hydro energy potential of Albania dictates that even in the near future the production of electrical energy should be based on hydro power stations. This conclusion is also favoured by other factors, as follows:
•Hydro power stations offer minimum environmental impact.
•Increased utilisation of this resource will open the possibility of export and exchanges of energy with neighbouring countries — ex-Yugoslavia or Greece.
•Albanian specialists have considerable experience in designing and building hydroelectric stations.
•There is in existence a complete legal framework for foreign investments in the sector.