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A Study of Hydroelectric Power:
From a Global Perspective to a Local Application

Prepared by:
Duane Castaldi
Eric Chastain
Morgan Windram
Lauren Ziatyk

Prepared for the
2003 Center for Advanced Undergraduate Studies and Experience
From Industrial Revolution to Industrial Ecology: Energy and Society
College of Earth and Mineral Sciences
The Pennsylvania State University

ABSTRACT
As energy becomes the current catchphrase in business, industry, and society, energy
alternatives are becoming increasingly popular
...
Numerous consideration factors exist
when building hydropower plants; whether the concerns are global or local, each has been
measured when discussing this renewable energy source
...


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TABLE OF CONTENTS
ABSTRACT

2

INTRODUCTION

3

Research Expedition Sites

5

Scope of Project

6

ENVIRONMENTAL EFFECTS

7

Physical

7
10

Biological
Flora

10

Fauna

11

Humans

13

ECONOMIC ASPECTS OF HYDROPOWER

14

Global Hydropower Economics

15

Local Hydropower Economics

16

Flat Rock Dam Hydropower Economics

17
19

BUILDING A HYDROPOWER PLANT
Consideration Factors

20

Construction

21

Plant Specifications

22

Intake

24

Penstock

25

Turbines

25

Generator, Transformers, and Electricity Generation

26

Development Configuration

27

CONCLUSION

28

WORKS CITED

29

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INTRODUCTION
Hydroelectric power captures the energy released from falling water
...

Ancient Greeks used wooden water wheels to convert kinetic energy into mechanical energy as
far back as 2,000 years ago
...
Humans in time began creating dams to store water at the most
convenient locations in order to best utilize power capacity (Australia Renewable Energy)
...

Hydroelectric power plants are categorized according to size
...
A Micro sized plant is one that generates
less than 100 kW of electricity and would typically be used to power 1-2 houses
...
A
Small plant generates 1MW-30MW and can serve an area while supplying electricity to the
regional grid
...
Hydroelectric
power accounts for about 10% of the total energy produced in the United States
...
This figure is based on environmental, legal, and institutional constraints
...

According to the US Hydropower Resource Assessment Final Report, there are a total of
104 projects that have a nameplate capacity of 2,218MW
...
It is
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located in Philadelphia County in the Delaware River Basin on the Schuylkill River and has a
nameplate capacity of 2500kW
...
It is built on top of a naturally existing fall
...
Boaters today use
the “slack water” for recreation
...
Irafoss
is located in Iceland and is one of three
power stations on the River Sog
...
The Irafoss station harnesses power from two falls, the Irafoss and Kistufuss, located
on the lower Sog
...
When it went online in 1953
it utilized 2 turbines that each generated 15
...
In 1963 an expansion of the plant added a
third turbine, which has a generating capacity of 16
...
Interestingly, one of the brands of
generators they use is Westinghouse Electric, International Co
...


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The Electric Mountain and Dinorwig Power Station in Wales in the United Kingdom is a
pump-storage facility
...
When water from the
upper reservoir is released energy is generated
...

The picture on this page is a schematic of the inner
workings of the plant
...


Scope of Project
While these are effective plants in their respective geographical areas, we wanted to
research the effectiveness of building a hydroelectric power plant in a more local region of
Pennsylvania
...
We chose to address economic and environmental considerations and then
propose a site in which to build a power plant and/or
make modifications to the existing area
...
We decided to
weigh the benefits and drawbacks to the flora and
fauna affected by the construction of a plant
...
Finally, we
studied the engineering specifications to satisfy as many environmental and economic concerns
as is possible while building an efficient plant with the correct amount of power generation
...

Complicating the matter even further, hydroelectric power generation is usually not the single
reason why a dam is constructed along a river
...
Since hydropower is generated from the dam, however, some of the
environmental implications should still be attributed back to the production of hydropower
...

However, it is important to understand all the consequences of hydroelectric power and the
existence of dams on rivers
...
Both the river and ecosystem of the surrounding land area will be
altered as soon as dam construction begins
...
This land
may have been used for other things such as agriculture, forestry, and even residences, but it is
now unusable
...

The reservoir that has been rapidly filling up with water immediately begins filling up
with sediment as well
...
The engineering
problem with sedimentation is that less power is generated as the reservoir’s capacity shrinks
...
This clean
water has more force and velocity then water carrying a high sediment load and thus erosion of
the riverbed and banks becomes problematic
...
Environmentalists must work to slow down the water by
creating barrages, although the effectiveness of these techniques is not exactly known
(Thorndike, 1976)
...
All the sediments that are now trapped in the reservoir previously ended up
in the delta
...
Sediments carried downstream during flood season
would build the delta back up again before the dam was constructed
...

Oftentimes some of the most severe environmental implications of a project occur during
the construction phase
...
Many new roads are built
which requires the removal of vegetation and topsoil since dams tend to be built in undeveloped
regions
...
The local impact becomes quite severe because of combining quarries with
new roads and dam construction
...

Another often-ignored environmental effect of dam construction is the impact on the
microclimate level
...
Temperate regions are also impacted with
“steam-fog” in the time period before freezing
...
Since water cools and warms
slower then land, coastal regions tend to be much more moderate then land-locked regions in
terms of temperature
...

Finally, one of the least studied and most disputed physical impacts of dam construction
is the possibility of inducing earthquakes
...
The theory is that added
forces of the dam along inactive faults seem to free much stronger orogenic tensions
...
While more research is needed on
this subject several disasters such as the Koyna Dam in India seem to provide some truth to this
theory (Biswat, 1981)
...


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Biological
Animal and plant life are impacted significantly by the dam construction
...
If the region was forested prior to the construction of the dam
the timber is harvested before the flooding begins
...
In addition, in very
cold climates such as Canada, deterioration of fully submerged trees occurs very slowly –
increasing the likelihood that the trees must be removed first (Biswat, 1981)
...

Flora
Another negative biological impact of dams is the growth of aquatic weeds
...
In Surinam, Lake
Brokopondo has become inundated with Eichhornia crassipes, which is commonly referred to as
water hyacinth
...
The impacts of weeds can be significant to water loss
...
Also, more water must be released
for irrigation purposes to ensure that an adequate supply makes it to the lower reaches of the
irrigation channel if there are weeds growing in the channel as well
...

Some disease rates such as malaria and schistosomasis tend to increase as weeds provide
a very favorable habitat for mosquitoes and other invertebrates that spread these diseases
...
In shallow water mechanical or manual clearing is by far the most
effective
...
Chemical herbicides work very well but bring about a
whole new set of environmental hazards to organisms, humans and the ecosystem in general
...
Finally, biological controls can be used to combat the
weed problem
...
The process of weed control often works best when mixing the three techniques
described above
...

Fauna
Animals tend to get the most attention from the press and public in general when dam
projects are proposed
...
Some animals such as
elephants, giraffes, and rhinoceroses are so large that this process is quite difficult and expensive
...
The creation of the dam does however create a new larger habitat for some
species of fish
...
The news for fish during dam construction is far from all good,
though
...
Anadromous fish, such as salmon, are hatched upstream in a freshwater

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environment but spend their adult lives at sea in the salt water
...
Since these fish rely on streams and rivers to get to and from different environments,
creating a dam makes a large roadblock for these animals to overcome
...
Without features such as fish ladders these fish
would die off
...

There are a number of measures that can be taken to help minimize fish mortality at
hydroelectric power plants
...
This can be accomplished by using better screens to capture the fish or
establishing diversion passageways
...

It is thought that gap sizes, runner-blade angles, wicket gate openings, overhang, and
flow patterns are the components that most lead to fish injury
...
Kaplan, Francis, and Bulb turbines tend to be safer for small fish with mortality rates of
only about thirty percent
...

Kaplan turbines are thought to be the most fish-friendly of the conventional turbines
...
Scientists and engineers hope to work together to
make changes to the design of turbines to ensure fish safety
...
By reducing the gaps there should be less
shear stress and grinding
...
Scientists are researching whether the route of passage through a turbine
has any impact on survival rates
...

Humans
Often the most discussed topic of building a new hydroelectric power plant is the
dislocation of large numbers of people
...
While
relocating may not seem problematic, consider the fact that many of these people come from
small villages where different cultural values and beliefs are held and all of the sudden these
villages are merged together in a new setting
...
This is especially troublesome in Africa where people have to leave behind
gods, shrines, and graves of their ancestors, all of which are very important to the local culture
(Biswat, 1981)
...
A significant reason why the Three Gorges Dam was not stopped despite the
environmental hazards was the benefits to those living downstream
...
Some proponents of hydroelectricity have pushed the issue of
increased recreation as a benefit to society
...
However,
this may not be as beneficial as it seems in the United States
...
Therefore, the recreational argument

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in favor of hydroelectric power is not very useful as many nearby residents will not want to see a
free flowing river stopped in favor of a large reservoir
...

Hydroelectric power emits no air pollutants
...
(Understanding Energy, 2003) While the environmental impacts of hydroelectric power
are very far reaching and in some cases severe, they do not always receive the same amount of
attention as the economic impacts
...


ECONOMIC ASPECTS OF HYDROPOWER
Economics is a branch of science concerning the distribution, production, and
consumption of services and goods
...
We need to learn about the economic structure and its function
in order to fully understand (on a global scale) trade relations between countries, why and how
(on a regional scale) a society works, and why (on a local scale) a business or factory fails or
succeeds
...
We also must consider the global
economics of such a renewable energy source as hydroelectric
...
The figures and statistics included in
several surveys analyzed are too exhaustive and detailed to include in a regional economic

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analysis; thus we will examine the areas in which costs are high or low, without providing too
many monetary examples
...
All forms of
(other) energy sources are affected by oil prices; when oil prices are low, the demand for
alternative energy is low
...
This thesis was tested in the
1970s when the oil embargo was in place
...

This is a very important factor in considering globalization and the relations of countries
...
The more dependent we are on a sole country the more
vulnerable we become
...

A national/regional economic factor which must be considered in the proposal of a
hydroelectric plant is the effect on the Gross Domestic Product (GDP) of a country with
consideration to the years of plant operation
...
S
...
As deregulation increases

business activity, relative prices for goods change quickly and dramatically
...
The "chain" method forces the government
to recalibrate the relative prices of these goods - and their relative importance to the economy every year

(USA Today)
...
S
...
Using data across the United States,
power plant sites were analyzed and assessed for economic cost and input to an area
...
When
evaluating a site, one must first consider whether it is already developed or not
...
In an
already developed area the only developmental costs that require consideration are structures,
improvements, and equipment
...
Several graphical representations are available to
demonstrate the increased costs associated with undeveloped sites
...
They include water for power, hydraulic expenses,
electric expenses, and rents
...

This site is complete with a pre-existing dam;
however, no electric generating power is present at the moment
...
It is of interest to note that the town of Manayunk where the Flat Rock Dam is
located was previously called “Flat Rock,” coined in 1810 because of an area of flat rocks in the
Schuylkill River
...
By 1819, the completion of the Flat Rock Dam, had aided much in
Manayunk’s prosperity and communication
...
It was in 1819 when the mills of Manayunk really started being built in large
numbers and immigrants (mostly from England) began operating the mills
...
Obviously jobs in
conjunction or related to the dam were plentiful during the height of river travel and commerce
...


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In order to evaluate this site for a hydroelectric power plant, we must consider the fact
that there is a pre-existing dam, the ownership of the dam (land use rights) and how much it will
cost to modify and maintain the dam (covered in the site construction analysis)
...
However, Lower Merion Township
maintains a boat launch and picnic area that provides recreational access to the pool and dam
...

The debate surrounding the economics and environment of the dam provides us with the
question of “Should the dam be used for maximum potential, or be maintained as is?” The dam
has historically provided a means of livelihood; however, what is its future potential? The Flat
Rock Dam was destroyed previously in a flood and rebuilt; the costs that accrued with rebuilding
were substantial
...
Historically it proved to be an invaluable asset to the
community
...
Though the Flat Rock Dam is a historically important site,
many environmental problems mentioned above have contributed to the idea that it should be
removed
...


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BUILDING A HYDROPOWER PLANT
The task for this project now turns to developing a site for a proposed hydropower plant
...
Now we will review our
choice of the Flat Rock Dam site for engineering considerations
...

The surrounding area must also be able to hold the water behind the dam in a manner that
will not extensively damage the surrounding area scenically or physically
...

The daily routines of the general public require a fluctuating need for power, with the
most electricity used during ‘peak demand’ times
...
Most producers of
electricity in the United States use natural gas-fired power plants to quickly meet the surge;
however, combustion of natural gas produces numerous gasses that pollute the environment
...

The United States Department of Energy subcontracts the Idaho National Engineering
and Environmental Laboratory (INEEL) to study hydropower throughout the country
...
In
Pennsylvania, major rivers available for damming include the Allegheny, Beaver, Delaware,

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Monongahela, Ohio, and Susquehanna
...


Figure 1: Potential power in Pennsylvania rivers (Conner, 1997)

INEEL provides a detailed listing of sites on each river available for power generation
...
(Flat Rock Dam Information)
...
These nineteen points are detailed in Table 1, below, and provide a solid argument for
developing hydropower in Manayunk
...
1 to 0
...
9 having the least impact on land and being the most likely for development
...
9
Wild/Scenic Tributary or Upstream/
Downstream Wild/Senic Location
0
...
9
Cultural Value
0
...
9
Geologic Value
0
...
9
Other Value
0
...
75
Scenic Value
0
...
9
Threatened/Endangered Wildlife
0
...
9
Federal Land Code 104
0
...
9
Federal Land Code 106
0
...
9
Federal Land Code 108
0
...
9

The Manayunk location in Southeastern PA remains an ideal candidate for construction
of a hydropower dam
...
Actually constructing this facility will require precise
knowledge of the site and dam dimensions
...
Dam size, retention basin size and depth, inlet valves, weir and
control gates, penstock length and diameter, turbines, generators, transformers and excitation
equipment, and efficiency all have to be examined
...
In our case we can achieve a maximum drop of 21 feet or 6
...
83 cubic meters per second
...
Using this information we can find out how much of the flow we need to achieve
2500kW
...
81*6
...
81)

e=efficiency (
...
15 m^3/s

H=Head in meters

%of flow used: 49
...
83=19%

Q=design flow, m^3/s
g=gravitational constant, 9
...
We will not divert much more than the needed 19% as to not
take away from the aesthetics of the dam and the rushing water
...


Plant Specifications
The next task is actually choosing the specifications for the plant
...
However, in the spot where our
power plant will sit, there will be a head of 21 feet
...
It is what controls the water; by damming up the water, the amount of water used to create
power can be determined
...
Building a dam requires much research, approval, time, and money
...
The size of the retention basin, or where
the water sits behind the dam, must also be considered
...
If the river carries
a large sediment load, sediment will build up behind the dam more quickly than if there is less of
a load
...
The dam also must go through an extensive approval and permit
process
...
Building dams and power
plants takes a lot of time and money as well
...
By choosing a site with an existing dam, all
that needs to be done is some modifications – a choice that will require a lot less time and money
(Woodward)
...
The following picture is a schematic of a power plant and all of its
component parts
...
The inlet valves and control gate
control how much water is going to enter the system
...
Three types that TOSHIBA Company of Japan offers are spherical or rotary, butterfly,
and thruflow
...
We chose a thruflow (pictured
left) as it has less head loss and leakage than the butterfly and
rotary (pictured right) designs (GE Power Systems and
TOSHIBA)
...
The weir
also is responsible for diverting the water
...
Three examples of intakes are the side intake without weir, side intake with weir, and
bottom intake
...
At low flows very little water will be diverted so
this type of intake is not suitable for rivers with great fluctuations in flow
...
This
design requires little maintenance but low flow cannot be diverted properly
...
It is very useful with fluctuating
flows and allows excess water to pass over the weir
...
It allows us the most flexibility and will be the most effective
and economic (Micro Hydropower Basics)
...
There are a
number of factors to consider when deciding which material to use in the building of the
penstock
...
When considering soil
type, you have to choose a material that will not be degraded or eroded by the surrounding soil
...
This is
why efficient planning is critical (Micro Hydropower Basics)
...
There are a
number of different models of turbines depending on which company the turbine is purchased
from
...
Two different types of turbines are impulse and
reaction turbines
...
Reaction turbines include the Francis, propeller, and Kaplan turbines
...
High head requires either a Pelton or
Turgo, medium head calls for cross-flow, multi-jet, or Francis, and low head requires cross-flow,
propeller, or Kaplan
...
Also, the cross-flow has to be horizontal and that will work the best with our
set up
...
A
crossflow turbine always has its runner shaft horizontal (unlike Pelton and Turgo turbines which

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can have either horizontal or vertical shaft orientation)” (Micro Hydropower)
...
It has an efficiency of up to 86%
...
025-13 cubic meters per second
...
Ossberger turbines are
relatively slow moving at 20-80 revolutions per
minute
...
From its specific speed
it is classified as a slow speed turbine
...
It flows through the blade ring of the cylindrical rotor, first from the outside inward,
then after passing through the inside of the rotor from the inside outward
...
The normal division in this case is
1:2
...
With this breakdown, any
water flow from 1/6 to 1/1 admission is processed with optimum efficiency
...

Generators, Transformers, and Electricity Production
Water flows through the turbine to turn it and its shaft to create mechanical energy that is
transformed into electrical energy by the generators and transformers
...
Two main
designs are the vertical or horizontal arrangements (TOSHIBA)
...
The water turns the
turbine, which turns the shaft and causes the exciter to send an electrical current to the rotor
...
This process creates a magnetic field, which creates an alternating
current, AC, by the moving of electrons
...
The generator and transformer sit in what is known as the powerhouse
...
From the powerhouse there are four main wires that
leave
...
These power lines are connected to the regional power grid (How Stuff Works, inc)
...
The tailrace is simply the pipelines that carry
the water back out to the river
...
Based
on how the dam and canal look in our scheme,
design b, the extended fall canal, looks to be
the best option
...


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CONCLUSION
After investigating the various impacts of a hydroelectric plant, we were able to
determine the feasibility of implementing a hydroelectric plant at the Flat Rock Dam
...
Also, taking into the
consideration that this is a highly scenic site of recreational value, we will only partially disrupt
the volume of water over the dam, using about 19 percent of the flow
...

Economically speaking, this project would benefit the community by providing energy as
well as employment opportunities
...
Because the residents of Manayunk will
benefit, any economic costs incurred by the building of a hydropower plant are justified
...
It would be classified as a small
hydro project generating 2
...
All materials involved in the construction would
be readily available
...
Overall, the Flat Rock Dam site appears to be a
good candidate for a hydropower plant due to its environmental, economical, and engineering
feasibility
...
From international power generating
stations to a potential local opportunity, we have realized the vast opportunities of this natural
resource
...
Commonwealth of Austrailia, Austrailian Greenhouse
Office, 1999
...
murdoch
...
au/ago/hydro/hydro
...
2001
...

10/1/03
...
dep
...
pa
...
htm
Conner, Alison M
...
Francfort
...
U
...
Hydropower Resource Assessment for
Pennsylvania
...
pp 6-11
...
Francfort, and Ben N Rinehart
...
U
...
Hydropower Resource
Assessment Final Report
...

Available: http://hydropower
...
gov/resourceassessment/pdfs/doeid-10430
...
ctcfoundation
...

htmlfs/4
...
pdf
Energy Efficiency and Renewable Energy, US Department of Energy
...
”
Last updated November 2003
...
eere
...
gov/RE/hydropower
...
10/13/03 http://www
...
com/photo/places/Philadelphia/Dam/
GE Power Systems
...
Available:
http://www
...
com
Hall, Douglas, Hunt, Richard, Reeves, Kelly, and Carroll Greg
...
S
...
June 2003
...
id
...
gov/pdfs/project_report-final_with_disclaimer- 3jul03
...
“How Hydropower Plants Work
...
©1998-2003
Available: http://people
...
com/hydropower-plant1
...
2001
...
10/11/03
http://hydropower
...
doe
...
shtml
Johnstone, John
...
com/philanet/Philadelphia/Manayunk
...
“Civil Work Components
...
Available:
http://www
...
net/intro
...
Ossberger Turbines
...
Available: http://www
...
de
TOSHIBA
...
” ©2001-2003 TOSHIBA Corporation
...
toshiba
...
jp
United States
...
Senate
...

Hydroelectric project in Pennsylvania : report (to accompany S
...
Washington,
D
...
: U
...
G
...
O
...
Morehead Valley Hydro, Inc
...
” Available:
http://www
...
com
Woodward, Dr
...
“Dam Geology,” The Dam Site
...
tig
...
au/~richardw/index

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