8209

• UCREFRP Catalog Number: 8209
• Author: Rochester, H., T. Lloyd and M. Farr.
• Title: Physical Impacts of Small-Scale Hydroelectric Facilities and Their Effects on Fish and Wildlife.
• USFW Year: 1984.
• USFW - Doc Type: 14-16-0009-82-020,
• Copyright Material: NO

Most of the hydroelectric facilities of the future will be small com-
pared to the 1 arge plants present ly supp lyi ng power in the Northwest and
the South. It has been estimated that the electricity needs of 14-20
million people could be supplied from small to intermediate facilities at
sites that have already been identified (Heutter 1978).

From a technical standpoint, SSH has the advantage of being a \'/ell
understood, proven technology, with an established infrastructure of
engineers, consultants, and suppliers. Project development can proceed
rapidly in most cases. SSH plants are capable of instantaneous start-up,
which makes them well suited for a reserve power role in energy-short
regi ons. SSH can often be used to advantage at remote sites where long
transmission lines from a major grid would be too expensive or impractical
and where the cost of transporting fuel for thermal electric generation is
prohibitive. Small-scale hydro is well suited for seasonal operation at
very sma 11 sites, such as ranches, lodges, and 1 umber camps, as long as
the season of maximum flow coincides with the season of greatest need or
sufficient water storage is provided and sufficient flow is avai lable for
competing and existing water users; e.g. agriculture, fisheries, etc.

The cost of generating electricity can be divided into two components:
capital costs and operating costs. For thermal electric generating plants,
operating expenses consist mainly of fuel costs. When fuel costs are un-
predictable (and sometimes rapidly increasing), it becomes more attractive
to invest in production facilities with relatively high capital costs, pro-
vided that future operating costs can be reduced or made independent of
fuel prices. Hydropower is such an investment.

Although the specific capital costs for hydropower depend on the
physical conditions at a site, the cost of construction per ki lowatt of
capacity is usually higher for a hydro facility than fossil fuel plants.
However, hydro has a significant advantage over fossil fuel and nuclear
plants in terms of operating costs because of the minimal fuel costs. In
addit ion, hydroelectric facil it ies last longer than other e lectri c power
plants and have a relatively simple operation that requires fewer operating
personnel and less maintenance expense. Annual operation and maintenance
costs usually vary from 2% to 5% of the total construction costs of a
hydroelectric project (U.S. Army Corps of Engineers 1979). The lifetime
economics of hydroelectric generation is competitive (depending on site-
specific costs) with other forms of energy production at many locations.
For example, small projects are often economically feasible in heavily oil-
dependent utility territories or at sites where existing civil facilities
reduce SSH construction costs.

Electrical power can be used either for some direct purpose, such as
running a factory, a pumping system, or some agricultural activity, or it
can be sold to a utility for general distribution through a grid system.
The latter use is the one most often proposed for SSH projects.

The demand for electricity from a typical utility varies fairly pre-
dictably over the course of a day and the days of the week (Fig. 3), as

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