Energy Resources Flashcards
Pros of coal energy
It’s reliable
Coal plants provide lots of jobs- lots of processes involved
It’s good for the economy: brought in $3.1 billion dollars to Kentucky
Cons of coal energy
Fossil fuel- releases SO2 and CO2 (acid rain and greenhouse gas)
Burning coal makes up 31% of all CO2 in our atmosphere
It’s non-renewable
How oil energy is made
Burn it and the heat produced- water to steam. Steam turns blades of turbine + turbine turns the generator (which is a magnet inside a coil)
Pros of oil energy
It’s reliable
It can be used to generate huge amounts of electrical energy
Oil is very abundant
Cons of oil energy
Fossil fuel- releases SO2 and CO2 (acid rain and greenhouse gas)
Drilling for oil pretty much destroys the environment
It’s non-renewable
How is coal energy made?
Crush it into a powder, then burn it. Heat produced- water to steam. Steam turns blades of turbine + powers generator
How is gas energy made?
Burn it and the heat produced- water to steam. Steam turns blades of turbine + powers generator
Pros of gas energy
It is widely used and contributes to 21% of the world’s energy production
It emits 45% less CO2 than coal and 30% less than oil
It is easy to transport via pipelines
When it is burnt, there is no waste produced like ash
Cons of gas energy
It’s non-renewable
It emits CO2 when it’s burnt
It contains 80-95% methane which is worse for the environment than CO2
If a country only has access to one gas source and that gas source is cut off, then that country is going to suffer terribly
How does nuclear power work?
The nuclei of atoms in uranium fuel pellets are split (nuclear fission) and lots of energy is released (kinetic). This kinetic energy produces heat inside a nuclear reactor- turns water to steam. Steam turns blades of a turbine and is attached to a generator- generates electricity
Pros of nuclear energy
Cost-effective alternative to fossil fuels
Doesn’t release any CO2 or SO2
It produces much more electricity per kg of nuclear fuel than fossil fuels
Cons of nuclear energy
Radioactive waste produced is really expensive to store (deep underground with thick concrete walls) and costs billions
It is also a threat to humans and the environment and stays with us for 200,000 years
Mining for uranium devastates the environment and waste produced is radioactive
Decommissioning a nuclear power station takes about 30yrs and costs billions
It takes a gas station seconds to start up but it takes a nuclear power station 6 months
How does wave energy work?
A chamber is built partially underwater with a small area on the surface allowing water to come in and out of it. Waves cause air above them to be forced in and out of a hole in the top of the chamber and a turbine is placed in the hole. Turbine turned by the air coming in and out. It’s attached to a generator which generates electricity
Pros of wave energy
It’s renewable
It’s reliable: there are always going to be waves
Wave farms produce so much energy- waves are so powerful (further out to sea they produce 100kW every meter)
Cons of wave energy
It isn’t predictable: you can’t control the features of a wave like speed or length
Very expensive
Power plants need frequent maintenance- lots of the parts are underwater- even more expensive
Plants can affect tourism when they’re visible from the shore- sea-side towns
How does geothermal energy work?
The splitting of nuclei (fission) in the earth causes rocks to heat up. Rocks heat up water deep under the earth’s surface. Resulting steam turns a turbine which has KE tf turbine turns a generator for electrical energy.
Pros of geothermal energy
It’s renewable
Its carbon footprint is almost non-existent; development of geothermal resources helps fighting global warming
Producing geothermal energy doesn’t require any fuel- the price stays pretty much the same harnessing the energy
Cons of geothermal energy
Geothermal power projects are expensive due to the drilling required to make a geothermal reservoir (one with the capacity of 1 megawatt typically costs $2-7 million)
Good geothermal reservoirs are quite rare- not many countries have enough good resources
Rain can damage the reservoirs- over the years it seeps through the earth’s surface and the reservoirs become exhausted if the water is removed faster than it is replaced
How does wave energy work?
A chamber is built partially underwater with a small area on the surface allowing water to come in and out of it. Waves cause air above them to be forced in and out of a hole in the top of the chamber and a turbine is placed in the hole. Turbine turned by the air coming in and out. It’s attached to a generator which generates electricity
Pros of wave energy
It’s renewable
It’s reliable: there are always going to be waves
Wave farms produce so much energy- waves are so powerful (further out to sea they produce 100kW every meter)
Cons of wave energy
It isn’t predictable: you can’t control the features of a wave like speed or length
Very expensive
Power plants need frequent maintenance- lots of the parts are underwater- even more expensive
Plants can affect tourism when they’re visible from the shore- sea-side towns
Wind energy
Wind turns blades of turbine- blades spin a shaft- shaft attached to generator- generates energy
Wind farms- lots of turbines in one place- more cost-effective
Pros of wind energy
Renewable
Cheap compared to other renewable resources
Doesn’t emit any harmful gases
It can be harnessed anywhere- huge potential
Space efficient- farming can be in between them
Prices are falling- new technologies- 80% in last 35yrs
Homeowners can harness their own energy
Cons of wind energy
Unreliable- wind does not blow consistently- some countries are windier than others
Turbines are large and unattractive- make a lot of noise
Built offshore- expensive
Threat to birds
Tidal
Tidal energy generators- built where there is high tidal movement- designed to get the motion of the tides- ebbing and surging
Tide ebbs or surges through the turbine- generator is connected
Pros of tidal energy
Renewable
Doesn’t emit harmful gases
Currents are predictable
Plants last for a long time- reduces cost
Cons of tidal energy
Plants have to be built near land- obstructs peoples’ views- can only be built at specific sites (20 with high potential)
Mudflats are damaged- causes marine animals to leave area
Power stations only produce power for half a day
Expensive to construct
Solar
Solar panels are made from silicon atoms. Bonds between these atoms are made of electrons
Solar panels absorb the light from the sun- one electron in the bond receives this energy and becomes mobile (becomes delocalised)- it creates a current
Pros of solar energy
Renewable
Harnessing the energy doesn’t cause any pollution- processes involved (manufacturing, transporting and building) do
It is silent
Definitely abundant- earth gets 20,000 times more power from solar radiation than is necessary to supply the whole world
Only need to be cleaned twice a year
Cons of solar energy
Unreliable- cloudy or rainy day- no energy produced
Expensive to store energy once produced- don’t normally have too much energy though
Production of solar energy- associated with emissions of greenhouse gases (nitrogen trifluride and sulphur hexafluoride)- more harmful than CO2
How do solar heating systems work?
Light energy from sun turns into thermal energy in water ∴ you can use hot water
