Hydro-power

I represents coal, El hydro power and other energy sources. Data from Reference 2. 

HSPF can handle a reach network of any complexity it can even handle situations where flows are split (diverted) and later recombined further downstream (e.g. through hydro-power diversion tunnels). Also, it makes no assumptions regarding the shape of the water body. For example, streams do not have to be represented with trapezoidal cross sections. 

Micro-hydro systems use the natural flow of water to yield up to 100 kW output of electrical energy [22]. Simplicity, efficiency, longevity, reliability, and low maintenance costs make these systems attractive for mral development [23]. Like solar and wind, the fuel source for microhydro power is free, and the use of hydro-powered turbines to generate electricity produces no on-site air pollution. 

Alternative Energy News Network. Micro Hydro Power- Pros and Cons [Internet]. Available at www. alternative-energy-news, info/micro-hydro-power-pros-and-cons [Accessed 2012-03]. 

Hydroelectricity, at present the most important of the clean, econonucally feasible, renewable energy options, can benefit from a water resources development project however, that is seldom the only benefit. It is clear, therefore, that hydro-power has an important role to play in the future, both in terms of energy supply and water resources development. 

Hydropower production is an especially important factor in many mountain regions. High water availability and large differences in altitude over short distances offer highly favorable conditions for hydropower. In the Alpine countries, the importance of hydropower is greater the higher the proportion of the Alpine area. In the case of Switzerland and Austria, hydropower amounts to 57% and 59%, respectively, of the total electrical production. In the Swiss Alps, the usable hydro-power production potential is largely realized (cf. Sect. 2.2 in [11], this volume). 

Hydro Power as the Dominant use of Water in the Alpine Region. 74... 

As Table 1 illustrates, Switzerland exhibits an extremely high specific aimual production of electrical energy from hydro power - by far the largest compared to other countries within Europe. This reflects the high level of water utilization, efficient production facilities, and a high density of power stations more than 90% of suitable rivers and streams are harnessed in Switzerland for this purpose [13]. 

With more than 1,200 power stations, the country generates around 57% (=35,000 GWh per year) of electrical energy from hydro power [15]. These power stations are supported by around 1,400 water intake structures [16] and some 200 reservoirs [17]. These artificial storage basins store a total usable volume of almost 4,000 million cubic meters, and are theoretically capable of temporarily retaining around 7% of annual precipitation. 

Hydro power (%) Wind power (%) Geothermal (%) Nuclear (%) Heat (coal, gas) (%) Hydro power (MWh km ) Total (MWh km )... 

Electricity is a fundamental requirement for economic growth, and hydro-electric power is often thought to be environmentally benign. However, the constraction and operation of many hydro-power dams have had significant negative impacts on the environment and raral economies. Reduced downstream flooding has destroyed fisheries and starved the floodplain soils of moisture and nutrients (Acreman, 1996). 

Where inexpensive electric power is available, for example off-peak hydro-power or nuclear power, hydrogen can be produced by electrolysis of water. Another approach is to use solar energy to "split" water into H2 and 02. The feasibility of this scheme depends on the development of catalysts that absorb sunlight and then use the energy to reduce water to hydrogen. 

Electrolysis using geothermal electricity Electrolysis using hydro power ... 

Power Plant Construction Wind Power Generation Hydro Power Generation Tidal Power Generation Wave Power Generation Solar Power Generation Thermoelectric Power Generation Biomass Power Generation... 

Wind Power Generation Solar Power Generation Hydro Power Generation... 

Armenia has hydro energy resources that can cover up to 35% of country s energy demand, but according to above mentioned, hydropower development has no much perspective in the country due to limitations of hydro-power resources and this could result environmental degradation, particularly lose of environmental quality of the Lake Sevan. However, the system of small hydropower plants on mountainous rivers could be developed as a support to Armenian energy grid. 

The Dniestr hydroelectric plant of 702 MW capacity with 1 TWh average annual power generation was put into operation on Dniestr river. The Dniestr hydro power cascade will include the biggest in Europe Dniestr hydro accumulating plant of 2,268 MW capacity and buffer hydroelectric plant. Fifty small hydroelectric plants of about 100 MW total capacity with 0.25 TWh annual power production are exploited in Ukraine. 

First Priority Potential Medium-Size Hydro Power Projects are Poilinsk HPP in the cascade of the Kura River and Gudialchay HPP at the irrigation project in Gudialchay River, which installed capacity are of 90 MW. 

Sayano-Shushenskay Hydro Power plant (Russia) 8.5 109 1.1 10 7... 

Autonomous power systems can be based on renewable energy (RE) units, such as wind turbines, photovoltaic systems or small hydro power stations and fossil-fuel generators. Due to the intermittent nature of renewable energy, storage devices and/or appropriate demand management strategies are necessary when conventional generators are not included in the system. 

Hydro power systems utilise the energy of flowing water for the production of electricity. A general consensus for the definition of small hydro power plants does not exist. The upper power limit varies from 2.5 to 25 MW, depending on the country, but 10 MW is the most acceptable one and has been proposed by the European Small Hydro Association (Thematic Network on Small Hydro Power, 2005). 

Small hydro power plants are usually of the run of river type. In such schemes electricity is generated when the water is available and provided by the natural flow of the river. When the river dries up and the flow falls below some predetermined amount, the plant generation ceases. 

The main components comprising a small hydro power plant are the civil works for the water diversion and the necessary mechanical and electrical equipment. Water is diverted from the river at the intake position, where a weir is built at an elevation higher than the power house. From that point, water is driven through a... 

For smaller hydro power systems, such a solution is considered to be complex and additionally a danger exists of rapid control valve movement introducing damaging surge pressure waves in the pipelines or instability in the overall control system (Roberts, 2002). A preferable solution to maintain frequency close to its nominal value is the utilisation of load control. For the implementation of this scheme, secondary or even dump controllable loads are switched on and off, according to frequency-deviation measurements. 

For the exploitation of available hydro power in a considered site, two physical quantities must exist, the flow rate of water and a head. Flow rate is the volume of water passing per second and it is measured in m3/s. Head is the water pressure, which is created by the altitude difference between the water intake and the turbine. It can be expressed by the relevant vertical distance. A classification of sites exists, depending on the head values (British Hydropower Association, 2005). Sites with heads less than 10 m are considered low-head , from 10-50 m are medium-head and above 50 m are classified as high-head sites. The power that can be produced by a hydro plant is expressed by the following equation ... 

Stavrakakis GS, Kariniotakis GN, (1995). A general simulation algorithm for the accurate assessment of isolated diesel-wind turbines system interaction, Parts I, II. IEEE Transactions on Energy Conversion, 10 577-590 Thematic Network on Small Hydro Power, (2005). Proposal for a European strategy of research, development and demonstration for renewable energy from small hydropower. http //www.esha.be... 

Fourth, electrolysis presents a path to hydrogen production from renewably generated electrical power. From an energy perspective, electrolysis is literally a way to transform electricity into fuel. Electrolysis is thus the means of linking renewably generated power to transport fuels markets. Currently, renewable solar, wind, and hydro power, by themselves, produce only electricity. 

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