Generating Electrical Energy Flashcards
what parts make up the national grid
step up transformer, pylons and cables, sub stations, step down transformer
describe how a nuclear power plant generates electricity
nuclear fission energy turns water into steam. Steam turns the turbine. Turbine spins generator
describe how hydroelectric power stations generate electricity
water is held in a dam. This then flows down a hill side and as it does it spins a turbine. The turbine spins a generator, creating electricity
describe the energy transfers occurring in a HEPower station
gravitational potential energy is transferred to kinetic energy. Kinetic energy is transferred to electrical energy in the generator
describe how tidal power stations generate electricity
water is moved up a river estuary by the gravity of the moon. It gains gravitational potential energy as it is held behind a barrier. A when released this energy is transferred to kinetic energy, which turns a turbine, which spins a generator
what does a pumped storage system mean for a HEPower station
energy can be stored in water in a dam. When demand is low, pumps take energy up to the dam. A when there is a surge in demand, water can be released to meet this, generating electrical energy needed
what is the advantage of short start up time
energy can be generated quickly to meet a surge in demand
4 advantages of overhead power cables
- easy to maintain
- relatively cheap
- use air to cool the wires
- they use air as an insulator
3 disadvantages of overhead cables
- they are an eye sore
- affected by weather
- dangerous to low flying objects
what is geothermal energy
energy from hot rocks
2 advantages and 2 disadvantages of nuclear power
+no CO2 produced
+reliable
- produces radioactive waste which is dangerous and tough to dispose
- long start up and decommissioning time
what are step up transformers used for in the national grid
they increase the voltage of the supply (and decrease current). This reduces the amount of wasted heat energy in the wires making the transfer of electrical energy more efficient
how can the amount of CO2 produced in burning fossil fuels be reduced without burning less fuels
carbon capture and storage. this is where CO2 is trapped in the power station and stored in large spaces like old oil well under ground or under the sea bed
2 fuels used in nuclear power stations
uranium 235 or plutonium 239
describe how a biofuel power station works
the fuel- wood, straw plant oil is burned to release heat energy. The heat energy then turns water into steam. The steam drives a turbine, which spins a generator.
