Technology Status - NET Nowak Energie & Technologie AG

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● Costs
Investment costs for SHP plants vary according to site-specific (e.g.
topography, hydrology) and local characteristics (e.g. planning and
administrative issues, social acceptance, finance schemes). The site is an
important factor in the technical choice for the SHP system and related costs,
whereas other local characteristics influence non-technical costs.
The most important system and cost elements are a) civil engineering,
b) equipment, and c) turbine. As a general rule, civil engineering costs are
higher for high-head plants, mainly because they usually need longer
pipelines. On the other hand, turbine costs are higher for low-head plants,
which have to pass more water than high-head plants for the same power
output and are therefore larger. Low-head power plants also run more slowly
and thus cannot be connected directly to the generator. Electrical equipment
(which includes the generator, the transformer, the controller, the protection
system and the access lines) represent about 25% of the total plant cost for
both high and low-head plants.
For supplemental hydropower systems, energy production is only a
secondary purpose. Therefore, civil engineering plays a less important role
because the most significant construction is already in place. The turbine and
the electrical equipment each cost approximately the same as the civil
engineering and must be adapted to the principal purpose of the plant.
Equipment costs can be highly variable, depending on the country and
location, the water source and the quality of equipment. Figure 9 shows an
example of SHP elements (turbine, electrical equipment and civil
engineering) and relative costs for three different types of SHP plant (highhead,
low-head and supplemental hydropower system). This figure helps to
identify the key elements where efforts can be made to decrease the overall
power plant costs.
Turbines are the most expensive standard component (as opposed to civil
engineering, which is highly specific for each site).
High-head plants tend to have lower investment costs; because the higher
the head, the less water is required to generate a given amount of power. As
a result, these plants can utilise smaller and less costly equipment. However,
there are disadvantages often associated with high-head sites. They are
generally located in areas with low population density and relatively small
local demand for electricity. Long transmission distances to densely
populated areas increase final costs. Also, easily- engineered high-head sites
are increasingly rare or difficult to develop.
SMALL HYDROPOWER X2