Hydroelectricity, waves and tides Flashcards
Hydroelectricity
requires flooding of valley by building a big dam. Water allowed out through turbines, no pollution.
2) Damage to environment due to flooding of valley
- rotting vegetation produce methane and CO2
- loss of habitat c species
- reservoirs looks unsightly when dried up
3) Putting hydroelectricity in remote valleys tend to reduce impact on humans
4) immediate response to increase demand of electricity
5) reliable except in times of drought
6) initial cost high, no fuel costs and minimal running costs are high
7) useful to generate electricity on small scale in remote area
Wave power
Lots of wave powered turbines located around the coast, moving turbines connected to a generator
2) no pollution but disturbs seabed and habitats of marine animals, spoiling view and a hazard to boats
3) fairly unreliable, waves tend to die out when wind drops
4) initial costs high, no fuel costs and minimal running cost.
5) useful to generate electricity for small scale
Tidal barrages - sun and moons gravity
Tidal barrages are big dams built across river estuaries with turbines in them . Tides come in, it fills up the estuary . Water allowed out through turbines at controlled speed.
2) Tides produced by gravitational pull by moon and sun
3) No pollution, main problems are
- preventing free access for boats
- spoils view
- altering habitat of wildlife
4) pretty reliable and tides happen 2x a day w/o fail and near to predicted height.
Tides is a variable , lower height = less energy produced than bigger tides.
- don’t work out when water level is same either side of barrage ( happens 4x a day because of ties )
- initial cost moderately high, no fuel cost and minimal running cost
- Potential for generating significant amount of energy
