Curtis LeBlanc

Introduction  Hydroelectric power converts the natural flow of water into electricity. The energy is produced by the fall of water turning the blade of a turbine. The turbine is connected to generator that converts the energy into electricity.  Hydroelectric power is the best know form of renewable energy.

Benefits to Hydro Power  No emissions of carbon dioxide, so it dose not contribute to the greenhouse effect.  Create clean electricity.  Allows the river to be controlled to prevent flooding.  The reservoir can be used for irrigation, and it is an artificial lake that can be used for recreation.  Requires little maintenance, easy to operate, and creates jobs.

Problems with Hydro Power  Flooding of the land to make the reservoir, which may be high-quality farm land. Many people may be displaced as a result. For example, the construction of the Aswan Dam resulted in the forced relocation of over people in Egypt plus another in Sudan.  Flooding forest land can release mercury from the soil into the river water. This was discovered in Manitoba after the division of the Churchill into the Nelson river to enlarge the flow for the Kettle Rapids Dam.

 Although the generation of hydro power is clean, the construction of the dam is not. Enormous quantities of concrete, steel, and other materials are required.  Dams also interfere with groundwater. The Glen Canyon Dam on the Colorado River has allowed groundwater to seep through the sandstone walls of the canyon. Landslips may occur since the water lubricates joints and faults in the rock.  Another major problem obstructions of the river for aquatic life.

 Since the dam slows the flow of the river the sediments suspended in the river are dropped in the reservoir raising the level of the water.  The water leaving the dam is at a higher velocity then before so the amount of erosion increasing changing the dynamics of the river.

La Grand River Scheme  La Grand is Quebec's third largest river. The La Grand river has been turned into series of lakes by the construction of dams. In addition six rivers have been diverted to enlarge the flow of the river, flooding over km. The damming of the La Grande river has caused many environmental problems.  For example, fish populations are affected. River species have declined and lake species have increased. This has caused the entire river ecosystem to change.

 Problems with mercury contamination has had an impact on the fishing in La Grande.  The change in volume of water that enters James bay is predicted to have a drastic impact on fish and wildlife, including polar bears and ringed seals.  Other wildlife can be affected. For example, in 1984 an estimated caribou drowned as they tried to cross at a time when surplus water was being diverted downstream.

Possible Solutions  Fish ladders solve part of the problem of the obstruction the rivers aquatic life.  Smaller scale hydroelectric power unites are the best alternative. The cost of such schemes is low, and very little land is flooded. The dams have little affect on the rivers natural flow and has a small impact on the surrounding ecosystem.  The best solution is to avoid major problems in the first place by proper planning and extensive research on the area.

Introduction  Wind power converts the energy form the wind into electricity. The wind turns the blades, which spin a shaft, which connects to a generator and makes electricity.  Wind power is one of the least damaging forms of energy.

Benefits to Wind Power  Wind power is clean it dose not produce any dangerous waist, nor does it contribute to global warming.  Its abundant and reliable.  It creates jobs.  The wind turbines are not noisy.  Wind energy is one of the safest energy technologies.  It is a tourist attraction.

Problems with Wind Power  It dose not produce very much energy for the price.  Require large amounts of area to be build on.  Wind power has a devastating effect on birds. In Northern California's Altamont Pass, more than 400 endangered or protected birds are killed every year by wind turbines, including golden eagles, red-tailed hawks, burrowing owls and kestrels.

Possible solutions  Better planning to maximize space and still get the same amount of power.  Improve the rotor design to make it lighter and more efficient.  Build them in locations which will less affect the local birds.

Conclusion  Both wind an hydroelectric power are good alternatives for fossil fuels and nuclear power plants.  They are not 100% clean and do have an environmental impact.  They both do not give off carbon dioxide which means they don’t contribute to the greenhouse effect.

Bibliography Stewart Dunlop., Michael Jackson. Understanding our Environment 2 nd edition. Oxford University Press (Canada) 1997 Somnath Baidya Roy. “Answers to huge wind-farm problems are blowin' in the wind.” December 15 th “Wind Power.” Alberta Agriculture and Rural Development. May 5 th 2008 “How Hydro Works.” Canadian Hydropower Association.