sustainable energy Flashcards
what are primary energy sources?
- fossil fuels
- nuclear fuel eg plutonium + uranium
- biofuels from plants
- wind, waves, sunlight
how is electricity generated?
1) fuel burned to produce heat which boils water producing steam
2) steam drives 2 turbines which power generators
3) electricity produced in generators sent to step up transformer then 2 ng
4) electricity distributed to homes through ng at high voltage
5) high voltages stepped down by transformer to mains supply voltage in our homes of 230V
what is renewable energy?
nuclear and fossil fuels cause enviro damage releasing co2 in atmos contributing to climate and global warming
what are alternative ways to generate electricity?
- wind
- waves
- hydroelectric power
- biofuel
- solar power
- geothermal
NOT RUN OUT
what are hydroelectric dams?
water stored in reservoir flows down pipes and turns turbines which powers generators
advantages - cheap energy
what are wind turbines?
force of wind turns blade of wind turbine proving power to a generator
advantages - free energy, inexpensive, need lil maintenance
disadvantage - only generate when theres enough wind
how do generators work?
produce electricity when a magnet rotates near a coil
generator can be driven by another energy source, burning fossils used to heat water and produce steam to drive a turbine
how do power stations work?
water has potential energy
what are the advantages and disadvantages of fossil fuels?
advantages:
- high energy output
- efficient
- used anywhere
disadvantages:
- non renewable
- acid rain
- green house gases
what are the advantages and disadvantages of nuclear?
advantages:
- no greenhouse gases
- high energy output
- reliable
disadvantages:
- expensive to remove fuel and for processing
- damages enviro
what are the advantages and disadvantages of biofuel?
advantages:
- renewable
- inexhaustible supply
disadvantages:
- greenhouse gases
- expensive (machinery)
what are the advantages and disadvantages of solar?
advantages:
- renewable
- no greenhouse gases
- no liquid waste
disadvantages:
- expensive
- need large surface for panels
what are the advantages and disadvantages of wind?
advantages:
- renewable
- no greenhouse gases
disadvantages:
- expensive
- noisy
what are the advantages and disadvantages of waves and hydroelectricity tidal?
advantages:
- renewable
- no greenhouse gases
disadvantages:
- expensive
- changes ecosystem by flooding
- limited locations
what are the advantages and disadvantages of geothermal?
advantages:
- renewable
- small emission of greenhouse gases
disadvantages:
- limited locations
- expensive to drill for suitable sites
how can you reduce energy demands in the home?
- installing double glazed windows
- loft insulation
- energy saving light bulbs
- switching off appliances
how can you reduce energy demands naturally?
- public transport
- recycling
- car sharing
how can you reduce energy demands in a work place?
- cleaning air conditioner filters
- low energy light bulbs
- roof insulation
- low energy machinery
- efficient vehicles for transport of goods
what are the environmental impacts of energy source?
- greenhouse gases
- nuclear power creates radioactive waste
- wind farms cause noise and visual pollution
- hydroelectric and tidal dams flood large areas
what should you consider when choosing an energy source?
- cost
- reliability
- how much waste produces
- impact on environment
what is power?
measure of rate of energy transfer, measured in watts (W)
calculate power using this equation:
power = voltage x current
potential difference:
potential difference = power
———
current
what is energy?
measured in joules
calculate energy transfer in joules and kilowatt hours:
energy transferred = power x time
whats the formula for calculating the cost of electrical energy?
total cost = number of units x cost per unit
explain waste from power stations:
radioactive waste
nuclear waste emit ionising radiation affecting body cells
when handling radioactive materials, danger of being exposed to radiation source outside your body - irradiation
if radiation gets on clothes or enters body, contaminated
