Imanov1, F.A., Ismayilov1 R.A. & Ahmedova2 B.V.
1 "Azersu" Open Joint Stock Company, Water Channel Scientific-Research and Design Institute, 2 Ministry of Education Republic of Azerbaijan, ’Republican Center for Development Child and Youth.
Keywords: hydropower potential, theoretical hydropower potential, technical hydropower potential, economical hydropower potential
Introduction
Hydropower is a key source for renewable electricity generation and has an important potential to be marketed as green power. The energy of flowing water is harnessed by turbines, which are placed in the path of the water flow. It can be converted in the form of electricity through hydroelectric power plants. Hydroelectric plants are classified commonly by their hydraulic characteristics, that is, with respect to the water flowing through the turbines that run the generators (Landy, M., 2016 ).
The notion “hydropower potential” is utilized to evaluate the potential energy what a water stock presents. There are in use several definitions for the hydropower potential:
The theoretical potential, with three levels:
The exploitable hydropower potential, with two levels:
• technical potential • economical potential
Hydropower’s theoretical potential includes the total potential energy from all water resources within specified spatial boundaries without any physical, technical and economic usage limitations. In practice, only a small percentage of theoretical potential can be harvested (Modi, S. & Lallement D., 2009).
Hydropower’s technical potential is defined as the total energy that can be generated under the technical, infrastructural and ecological constraints. Usually, technical potential ranges from 20 to 35 percent of theoretical potential. Hydropower’s economic potential is defined as the energy capacity that is economically exploitable relative to alternative energy forms.
Materials and methods
The power potential of flowing water is a function of the discharge (Q), the specific weight of water and the difference in head (H) between intake point and turbine. In Equation (1), the two parameters, Q and H, need to be calculated. If Q and H are known for a given segment of a stream, the hydropower potential can easily be estimated for that segment (Bahadori A. et al. 2013).
The geometric or statistical pressure is equal to the difference between the upper ΔYB and the lower AB level:
The water discharge Q is used to generate electricity in the m3/sec. The power is measured in N - units of work divided by time. The power measured in W(Watt).
P=ρgQH=γQH=9810QH (2) Where, ρ-the density of water, g-acceleration of gravity, m2/san P = 9.81QH
Potential hydroenergy resources (theoretical reserves) are determined by the following formula:
∑
∈Where, E is energy, in kWh; Q is average annual water consumption, m3 / s; H is the fall of the river in according section, m.
Result
55 small hydroelectric power stations were built on the small rivers of Azerbaijan in the 30s-40s of the last century. However, after the launch of the Mingachevir hydro power station in 1953, these small HPPs were essentially lost and their operation was discontinued (Imanov F.A., 2007; Rustamov S.G. & Kashkay R.M. 1989 ).
At present, it is planned to construct new small HPPs in several rivers to effectively use alternative energy sources.
This assessment uses hydrological data from 68 observation stations on the 42 rivers of Greater Caucasus region of Azerbaijan, from 62 stations on the 34 rivers of the Lesser Caucasus region, 26 stations on the 12 rivers of the Nakhchivan and data from 39 stations on 28 rivers of in the Lankaran province. In general, hydrological observation data of 195 observation stations on 116 rivers of Azerbaijan were used. The results of the calculations are shown in Table 1 for a few river examples.
Table 1. The hydropower potential of small rivers of Azerbaijan
№ River Station River
The total hydropower potential of all small rivers of Azerbaijan is 4.508 billion kW/hours(Table 2).
Table 2. Evaluation of hydropower potential of the rivers of Azerbaijan according to provinces Provinces Power of the river, mln kWt Energy of the river,
billion.kWt.h
Greater Caucasus 2,10 1.838
Lesser Caucasus 2,08 1.823
Nakhcivan 0,61 0.535
Lenkaran 0,36 0.312
Total 5,15 4.508
The main findings of the research are:
to assess the hydro energy potential of small rivers has been created (hydrological and morphometric) data base
• Hydropower potential of small rivers is estimated (5.15 million kWt).
At the next stage it is proposed to carry out the following tasks:
• Calculation of technical and economic indicators of hydropower resources of small rivers;
• Creating a hydroenergy cadastre of small rivers for each administrative district;
• Preparation of proposals for the protection of river ecosystems, when small HPPs are built on small rivers.
Discussion
However, it should be noted that the small HPPs that don’t have the capacity to regulate flow are in line with the river regime. Therefore, in the dry and poor water period, such HPPs have significantly less power than the design capacity (up to zero). Such conditions create a breakthrough in energy supply of consumers.
Therefore, small HPPs must be connected to local power lines fed from other sources.
Small HPPs can be built not only on small rivers, but also on irrigation canals that aren’t very large.Sometimes, the small rivers are important for water economy. The use of height differences created by these points in order to obtain energy doesn’t require much spending.
At present, interest in small hydropower in different countries is increasing day by day. Thus, state commissions, committees, institutions are created to conduct research to use energy of small rivers.
Rivers as traditional energy source have some advantages. The main advantage is that hydroenergy is environmentally friendly.
References
Imanov F.A. «Water infrastructure of Kura river basin within Azerbaijan» / International congress river basin management.
Volume I. 22-24 March 2007 Antalya – Turkey.
Sust. Energ. Rev.Australia, 2013.
Rustamov S.G., Kashkay R.M. Water resources of Azerbaijan, Baki, «Elm», 1989, 182 p.
Landy, M. “A methodology to quantify the environmentally compatible potentials of selected renewable energy technologies”.
ETC/ACC Technical Paper 2010/16, Harwell.
Modi, S., Lallement D., Energy and the Millennium Development Goals, The Energy Santor Management Assistance Programme, United Nations Development Programme,USA, New York, 2009.