Hydroelectricity Source Presentation
My notes:
Slide 7:
● Hydrokinetic energy:
○harness power of natural water currents (big and small), waves, ebb/flow of tides
○energy from rivers and oceans
○buoys - harness vertical/horizontal currents
○water turbines to catch power of waves
○US Energy Department currently supporting research
○withstand water turbulence, preserve surrounding env.’t
○lots of oceans/rivers very close to large populations
●
Slide 8:
●environmental effects of dam differ from dam to dam
○depends on location, climate, ecosystem, surrounding environment, etc. of each dam
○can only be described in a broad context because each hydroelectric dam is very different from other dams.
●Non polluting
○does not pollute air or water.
● Needs large reservoirs, which can:
○inundate the surrounding area
■flood over (make inaccessible) agr. fields, archaeological sites, animal/plant habitats, human settlements.
●water levels can raise anywhere from a few feet to even hundreds of feet, to generate the most power from falling water.
●ex.:
■displace organisms
■ex.:
○temp. saturation:
■slower water gathers more thermal energy
■colder water sinks to bottom of reservoir, causing water heat stratification
■cooler water generally has less oxygen.
○supersaturation: falling water from dam (if large drop) can cause lots of additional nitrogen to become dissolved into the water.
■Fish exposed to a sudden change in dissolved nitrogen levels can sustain injury and possibly die.
○release methane into atmosphere.
○sedimentation - sediment builds up behind dam.
■degree of severity of sedimentation depends on the dammed river’s ability to push the sediment through the dam.
■downstream habitats deprived of nutrients b/c the nutrients are blocked behind the dam
■oxygen depletion - more nutrients increases pop. of organisms in dam, which necessitate a higher intake of oxygen.
○alter flow of river
■affects river-dwelling and river shore-dwelling organisms
■displace organisms
○erosion
■rising riverbanks can raise banks of river to where there is no vegetation - soil will erode.
●affects what organisms can be supported.
●can increase sedimentation in the reservoir.
○fish
■disrupt migratory patterns (particularly of salmon)
■benefit some fish over others (good for warm water fish, opportunistic fish that wait by spillover to catch fish)
■disorient/fatigue fish; easier for predators to catch.
○fowl
■habitats can be inundated
■change from river habitat to reservoir (wetlands) habitat
What I did and what I learned:
After creating group norms and establishing channels of contact, my group and I began to research hydroelectricity. We began to compile our research into the powerpoint. I compiled relatively in-depth notes about my slides, and when we had to present, I made sure to elaborate on my topics using my notes.
I learned that making elaborate notes really helps make a presentation interesting, and rehearsing the presentation with the group can help eliminate some simple but high priority problems.
Slide 7:
● Hydrokinetic energy:
○harness power of natural water currents (big and small), waves, ebb/flow of tides
○energy from rivers and oceans
○buoys - harness vertical/horizontal currents
○water turbines to catch power of waves
○US Energy Department currently supporting research
○withstand water turbulence, preserve surrounding env.’t
○lots of oceans/rivers very close to large populations
●
Slide 8:
●environmental effects of dam differ from dam to dam
○depends on location, climate, ecosystem, surrounding environment, etc. of each dam
○can only be described in a broad context because each hydroelectric dam is very different from other dams.
●Non polluting
○does not pollute air or water.
● Needs large reservoirs, which can:
○inundate the surrounding area
■flood over (make inaccessible) agr. fields, archaeological sites, animal/plant habitats, human settlements.
●water levels can raise anywhere from a few feet to even hundreds of feet, to generate the most power from falling water.
●ex.:
■displace organisms
■ex.:
○temp. saturation:
■slower water gathers more thermal energy
■colder water sinks to bottom of reservoir, causing water heat stratification
■cooler water generally has less oxygen.
○supersaturation: falling water from dam (if large drop) can cause lots of additional nitrogen to become dissolved into the water.
■Fish exposed to a sudden change in dissolved nitrogen levels can sustain injury and possibly die.
○release methane into atmosphere.
○sedimentation - sediment builds up behind dam.
■degree of severity of sedimentation depends on the dammed river’s ability to push the sediment through the dam.
■downstream habitats deprived of nutrients b/c the nutrients are blocked behind the dam
■oxygen depletion - more nutrients increases pop. of organisms in dam, which necessitate a higher intake of oxygen.
○alter flow of river
■affects river-dwelling and river shore-dwelling organisms
■displace organisms
○erosion
■rising riverbanks can raise banks of river to where there is no vegetation - soil will erode.
●affects what organisms can be supported.
●can increase sedimentation in the reservoir.
○fish
■disrupt migratory patterns (particularly of salmon)
■benefit some fish over others (good for warm water fish, opportunistic fish that wait by spillover to catch fish)
■disorient/fatigue fish; easier for predators to catch.
○fowl
■habitats can be inundated
■change from river habitat to reservoir (wetlands) habitat
What I did and what I learned:
After creating group norms and establishing channels of contact, my group and I began to research hydroelectricity. We began to compile our research into the powerpoint. I compiled relatively in-depth notes about my slides, and when we had to present, I made sure to elaborate on my topics using my notes.
I learned that making elaborate notes really helps make a presentation interesting, and rehearsing the presentation with the group can help eliminate some simple but high priority problems.