Download NATS 1840 Lecture 20

NATS 1840 - Lecture 20 - Hydroelectric Power
- Canada 60% hydro, 90GW capacity, third largest hydroelectric energy producer
in the world (behind China and Brazil)
- Norway almost 100% hydro
- James Bay Project: series of hydroelectric dams on the La Grande River in
Quebec, diversion of rivers
- Damming rivers creates reservoirs, individual La Grande complex reservoirs over
1000 km2 in size, some dams as tall as 50 stories
- North of Quebec, populations sparse, industrialization non-existent, native
hunting and fishing prominent
- Facility generates approximately 15,000 megawatts = 16 CANDU reactors
- Quebec electricity system provides approximately 35,000MW, 90% + hydro
- 20 billion to build complex
- Initial resistance, settlements to Cree and Inuit populations
- 1975 agreement with Cree and Inuit, cash settlement, fishing and hunting rights
- Extensive environmental consultation and analyses, scientifically informed
management of nature on a large scale
- “Green” project, carbon neutral and thus not a contributor to global warming
- Formal approval of native Canadian populations
Changing Nature
- Environmental concerns secondary to maximizing efficiency and power
generation
- Flooding destroyed a wide variety of plant and animal life (beaver, muskrat, hare,
otter, birds)
- Destroyed hunting areas used for thousands of years. 83,000 km of shoreline
- Reservoir drops in winter (high demand), rises in summer (demand low)
- Flooding and trees
- Dead trees, fluctuating levels of water, large lifeless zone around reservoir
- Tributaries diverted to increase La Grande River flow drop in level, eliminating
species such as sturgeon, muskrat and beaver
- Heavy erosion of the banks of the La Grande
- Millions of trees planted for reforestation and erosion reduction, small portion of
total facility
- 1977 environmentalists and ecologists hired, approach cosmetic (moving around
topsoil) or simply a technological fix (sills, smaller dams to raise local water
level)
- For example, rather than clear timber before flooding, dead trees were harvested
and burned in a floating incinerator
- 45 biologists (in house scientists) completed survey of area
- Species adaptation: caribou radiotagged, new calving grounds and migration
- Animal culling
- Management of water flow, fiscal and productivity concerns
- 1984 redirection of water in system combined with heavy rains to lead to a herd
of 10,000 caribou drowning
- Narrow interests, blind to potential impacts
-
Scott: large scale management to maximize productivity leaves out local
information with various costs and consequences
McCutcheon: changing physical environment unpredictable despite use of science
Fish populations shifted, cold lakes and shallow river species increased in number
Reduction in biodiversity
Unintended consequence: increase in levels of poisonous methylmercury
Mercury in food chain, concentrated in species higher up the chain
Native populations and health risks from fish consumption
Changing native fishing patterns (social fix)
Is Hydroelectric Power “Green”?
- Project claimed to be environmentally sound, millions spent on studies
- Science determines impact, does not change direction, scale or management,
environmental concerns secondary to profit and productivity
- Northern ecosystems appear to be adaptable to change
o it takes time for the full impacts to be felt
o no independent data on the ecosystem before the project
- Major changes in land and its use, population levels
- Overall reduction in biodiversity
- Maximizing power output versus minimizing environmental impact, adaptation of
ecosystem