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Water for Energy and Fuel Production
Due to all these environmental benefits, the use of hydroelectricity for power generation
will grow worldwide over the next several decades.
13.2.6 Size And CAPACiTieS oF hydroeleCTriC PoWer FACiliTieS
While there are no official breakdowns of the type of hydroelectric power plants,
they are generally categorized based on the amount of power generation into
four parts:
1. Large power plants (generally >10 GW)—Currently, there are three such
plants in the world: Three Gorges dam (22.5 GW), Itaipu dam (14 GW), and
Guri dam (10.2 GW) [1–13].
2. Small power plants (generally with capacity up to 10–30 MW) with significant growth in China, Japan, the United States, and India [14–16].
3. Micropower plants (generally with a capacity up to 100 kW) provide power
to isolated home or community [17–25].
4. Picopower plants (generally with power capacity under 5 kW) used in remote
community requiring small amount of electricity [26–32] (Zainuddin et al.,
2012, pers. comm.).
Since we already examined some details on large hydroelectric power generation, in
Sections 13.2.6.1 through 13.2.6.3, we briefly assess some of the characteristics of
small-, micro-, and picopower plants.
13.2.6.1 small hydropower Plants
Small hydropower plants are generally used in a small community or an industrial
plant [14–16]. They may be connected to conventional electrical distribution networks as a source of low-cost renewable energy. They are also often built in remote
areas where it would be uneconomical to provide electricity from national electrical
distribution network. They have low environmental impact. In a typical installation,
water is fed from a reservoir through a channel or pipe into a turbine. The pressure
of the flowing water on the turbine blades makes the shaft to rotate. This rotating
shaft is connected to the electric generator, which converts the motion of the shaft
into electrical energy. Small hydropower plants can be further subdivided into minihydro, which has production capacity of less than 1000 kW [1,14–16].
13.2.6.2 microhydropower Plants
These type of power plants produce electricity up to 100  kW using flow of water
[17–25]. The installation is often just a small dammed pool at the top of a waterfall, with several hundred feet of pipe leading to a small generator housing. They
are useful to provide electricity to a small community. This type of power plant
is frequently accomplished with a Pelton wheel for high-head, low-flow water supply. Construction details of microhydropower plant are site specific. The production
range of such systems is often calculated in terms of “head” and “flow”; the higher
each of these are, more power can be generated. The construction of such a power
station requires an “intake” structure where water is diverted from natural stream,