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 Energy part 2 covers alternative energy for generating
electricity using hydro-power and stored energy
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
Energy
Alternative Sources of Energy
 Electrical Energy
 Hydroelectric (dams, turbines, tidal,
ocean currents, etc.)
 Stored Energy
 Nuclear Energy
 Wind Energy
 Solar (multiple sources)
 Biomass/Algae
Require more
investment in U.S.
power grid WHY?
Electrical Energy Alternatives
Hydroelectric I - Dams
 Advantages of Dams
 Existing form of energy production (2.4 % in the U.S.)
 Have a very low relative cost to operate (<½ coal)
 Do not produce hazardous by-products (waste or air
pollution)
 Once built can have a very long life decades or longer
 Reservoir can be used for recreation purposes & irrigation
 Stored water is a constant energy source
Electrical Energy Alternatives
Hydroelectric I - Dams
 Disadvantages of Dams
 Expensive to build, especially if they are to last
(sediment issue)
 Impact large area upstream (reservoir – people &
wildlife)
 Jurisdiction issues on rivers between adjoining
states/nations
 Rise of local water table is possible
 Interruption of sediment flow on rivers
 Impact on flushing of water pollution
Niagara Falls, USA
Hydroelectric Dams
Three-Rivers Gorge Dam, China
Sediment build-up behind this
dam is of special concern
But it will produce electricity
for 100 million people
Three-Rivers Gorge Dam
Environmental Impact
Baiji, Yangtze
River Dolphin
Siberian
Crane
Electrical Energy Alternatives
Hydroelectric II - Dams
 Of the 80,000 dams in the U.S. only ~3% are
used to generate electricity.
 Though expensive to build, dams that generate
electricity are relatively inexpensive to operate –
therefore the U.S. is missing a large opportunity
to use an already expensively built resource.
Electrical Energy Alternatives
Hydroelectric II - Dams
 Though expensive to build, dams that generate
electricity are relatively inexpensive to operate –
therefore we are missing a large opportunity
here to use an already expensively built
resource.
 New York State has over 600 registered dams,
not including many associated with the lock
system on the barge canal. Most do not
generate electricity but could be retrofitted to
capture this energy source.
Electrical Energy Alternatives
Stored Energy I – Pumped Stored Hydroelectricity
Utilization of
water pumped to
higher elevation
to store energy
for periods of
high demand.
Electrical Energy Alternatives
Stored Energy I – Pumped Stored Hydroelectricity
During periods
of low electrical
demand excess
(low Cost)
electricity can
be utilized to
run pumps to
store water at higher elevation, and then during periods
of higher demand the water is released and electricity is
produced through turbines in the system.
Electrical Energy Alternatives
Stored Energy I – Pumped Stored Hydroelectricity
Due to energy losses in the turbines and during pumping
this system is a net energy consumer, but if run correctly
will run at a net profit.
Electrical Energy Alternatives
Hydroelectric II - Tidal
 Usually involves creation of ‘tidal-dams’ or free
standing turbines in estuaries to capture flow and
drive turbines
 Advantages
 Do not produce hazardous by-products (waste or air
pollution)
 Located in areas that are otherwise not being
utilized
Electrical Energy Alternatives
Hydroelectric II - Tidal
 Disadvantages
 Relatively costly to build & cost to operate is variable
 Would be limited to coastal regions, and only those
with relatively large tidal fluctuations
 Has intermittent energy production (though this is
completely predictable)
 Can impact organisms that live in these areas
(especially those associated with estuaries – which
generally have larger tidal effects)
Examples of Tidal Energy
Production
Tidal energy dam in La Rance, France; 240 MW
Electrical Energy Alternatives
Hydroelectric III – Ocean Currents
 A potentially very
important source of
electrical energy
 Currently it is only
speculative in nature