Topic 2 Flashcards
Formation of oil and natural has
Millions of years ago small animals and plants died and fell to the bottom of the sea. Their remains are covered by sediments. As the sediments start forming layers, the sediments start to change into sandstone as the temperature and pressure increase. The heat and pressure turn the remains into crude oil and natural gas.
Formation of coal
Huge forests grew millions of years ago covering most of the Earth. 0 The vegetation died and formed peat. o The peat was compressed between layers of sediments to form lignite (low-grade coal). o Further compression and heat formed coal over millions of years.
Biofuels
Biofuels (bioethanol, biogas (methane), biodiesel and wood):
These produce a massive amount of energy during combustion that is used to heat water and convert it into steam, which drives the turbines to turn the generator to generate electricity.
Advantages
Renewable
Growing more plants takes more carbon dioxide.
Lower level of air pollution than fossil fuels (carbon neutral).
o Plentiful supply of plants (widely available) and inexpensive.
Disadvantages
Carbon Dioxide and toxic gases are released when burnt.
Lot of land needed.
o Shortage of land for agriculture so increase in food prices.
o Deforestation and loss of habitat so reduction in biodiversity.
o Produces less quantity of electricity than fossil fuels
Geothermal
Geothermal Power:
Cold water is pumped underground into a layer of hot rocks.
The rocks heat the water.
Water is changed into steam and steam is piped to the geothermal power station. The steam moves the turbine, which turns the generator to generate electricity. Can be used in places where magma comes close to the surface.
Advantages
o Doesn’t produce Carbon Dioxide so doesn’t contribute to global warming.
o Renewable.
Disadvantages
o Only certain areas have suitable conditions (due to lack of volcanoes)
o Expensive to install and need high level of technology
Nuclear power
Nuclear Power:
Uranium, a radioactive element is used as a fuel, releases huge amounts of energy when
nuclear fission (splitting of the atom) occurs.
Water is pumped into reactor
This energy from uranium is used to heat the water to produce steam.
The steam turns the turbine, and the turbine turns the generator which generates the electricity.
➤ Plutonium can be used as an alternative to uranium.
Advantages
Doesn’t produce Carbon Dioxide so doesn’t contribute to global warming.
o Large amount of energy is produced with a small amount of fuel.
o Provide job opportunities.
It’s a reliable supply of energy so can meet increasing world demand.
Small volume of waste.
Disadvantages
o Risk of radiation leakage eg, Chernobyl
-cancer or mutation
o Radioactive waste cannot be recycled since it is active for centuries
Nuclear waste is difficult to dispose.
Limited supply (non-renewable).
o Visual pollution.
o Expensive and technically difficult to build.
Solar power
Solar Power:
A bank of cells organized into solar panels produce a significant amount of electricity. Uses photovoltaic cells that produce a small electric charge when exposed to light.
Advantages
Solar Power
Doesn’t produce Carbon Dioxide so doesn’t
contribute to global warming.
Renewable.
No fuel cost.
O Once installed operation cost is low and it’s very economic where there is plenty of sunshine.
Disadvantages
Weather dependent so power may not generated when the sky is cloudy.
o Not reliable in some places
o Solar cells are expensive.
O Energy only produced in day light, so no power generated at night.
o Cost of storage of solar energy is expensive.
o Visual pollution
Demand for energy
Domestic demand:
The domestic demand is increasing due to the rapid population growth.
Most of the purchases that are considered necessities now increase the demand for energy
supplies, notably electricity.
Industrial demand:
。 Manufacturing requires the use of large amounts of energy throughout the production
e.g., iron and steel production.
o Advanced manufacturing techniques made the products that were once luxury items, cheaper
so, more people want to buy them.
The demand for the product increases.
The demand for energy (needed for production) also increases.
• Transport:
Manufacturers supply customers across the globe.
o This decreases production costs in countries that import but increases the transport costs as they require large amounts of fossil fuels to operate.
Personal and national wealth:
If economic conditions are good:
Employment
Higher employment.
More money to spend on luxury items.
Increase in demand for the product.
Increase in demand for energy (for
production). More industrialization and urbanization
If economic conditions are poor: urbanatic Product
Families have less money to spend on
luxury items
Need to make savings
Reduce the use of fuel
Reduce the purchase and use of electrical
items
Decrease in the demand for energy.
O Decline in the economy of one country
can have global impact.
E.g.: Reduction in the economy of China meant worldwide:
Reduction in production of steel.
Decrease in the amount of manufactured goods (transported by ships).
Decrease in the price of oil (energy source).
• Climate:
o People living in a temperate climate are likely to experience colder winters, so the energy demand for heating would be far higher.
They also experience fewer hours of daylight which increases the usage of electrical lighting. Climate change (excessive heat or cold) increase the energy consumption (particularly in urban areas) due to:
Need for additional heating.
Installation and operation of air-conditioning units.
How to conserve energy
Strategies for the efficient management of energy resources:
1- Reducing consumption:
Reducing the amount of energy used to heat a building.
A-Insulation: constructing using material with good insulation properties prevents loss of heat
Loft insulation: adding an insulation layer into the roof
space.
Under floor insulation: adding an insulation layer on the floor e.g., carpet.
Cavity wall insulation
Double glazing: two panes of glass with a gap in the middle to act as an insulator. This sealed gap is usually filled with air or an inert gas e.g., argon.
Triple glazing can also be used, but it is too expensive.
B-Turning electrical devices off when not in use
C-Using energy efficient devices and vehicle
D-Use windows to allow ventilation and increase light levels.
2- Energy from waste cooking oil:
Anaerobic digestion: breaking down of organic matter (waste food and vegetation) using bacteria anaerobically (in absence of oxygen) in a sealed container (anaerobic digestor) to release methane (a BIOFUEL and a flammable gas) that can be used for heating purposes to
heat water and turn it into steam that rotates the turbine, and the turbine rotates the generator to produce electricity.
Advantages
- Good for organic waste
- Doesn’t require technical knowledge.
- Reduces spread of disease
- No waste disposed so reduces contamination of water (water pollution) and air pollution.
- Processed waste can be used as fertilizers.
- Waste oil is recycled so cheap
Disadvantages
- Produces poisonous gases during combustion.
2.
Can only be used on organic matter,
- Limited generation of electricity
■ Vegetable oils, once used, cannot be used again for cooking meals. These oils can be collected and recycled into biofuels.
3- Exploiting existing energy resources:
The current solution is to use a renewable resource as a primary energy source when possible and have a fossil-fuel (or biofuel) powered station available as a backup when (weather conditions are not suitable.
This is a reliable technique for industry and household, reduces the amount of fossil fuels used.
clependent wind
4- Education of people for energy conservation:
The message must be that significant savings in energy bills can be made over the longer term reducing energy use.
Incentives to encourage the purchase of more efficient technologies.
Energy-efficiency ratings must be provided for new products to compare with the old ones
Replacing older, inefficient electrical devices.
Scrapping older, inefficient cars that emit more pollutants.
Laws passed by the government to make changes rapidly.
Hat
Stricter building regulations: new constructions must be more energy efficient.
Preventing the sales of inefficient types of electrical devices.
5- Transport policies:
Improving public transport so it is easier and cheaper than using cars.
Improving routes for cyclists and pedestrians.
Encouraging car-pooling.
Government incentives to use electric or hybrid cars as they don’t use fossil fuel and hence no CO2 emissions.
Restricting when cars can be used e.g., odd even rule in Delhi.
Providing incentives to buy more fuel-efficient vehicles and for vehicles using cleaner technology.
Regulations regarding the quality, of exhaust gases from
vehicles.
Check on the fuel efficiency.
Restrictions on where vehicles may go.
Taxation on fuels.
additional fees for travelling to certain places at peak times.
6- Research and development of new energy resources (Fracking): Obtaining oil or gas from shale rock by splitting them open using water, sand and chemicals. A vertical hole (2-3 km deep) is drilled to reach the fuel-rich rocks (shale rocks). Water, sand, and chemicals are pumped down under high pressure into the shale rock layer. This causes the rock to fracture, releasing oil and natural gas, which are forced back to the surface and collected.
Purpose of the three components:
Water: easy to handle (in high pressure).
Chemicals: stop the blockage of pipes.
Sand: keeps the cracks in the rock open.
Advantages
Access to more oil and gas
Less pollution than burning coal
The need to import reduces
Provide many jobs locally.
Disadvantages
Toxic chemicals from fracking might enter the water sources
Uses a lot of water so it may cause water scarcity
o Noise, land, air, and visual pollution
Natural areas damaged so loss of habitat
Occurs
May cause additional Earth tremors.
Types of sources of enegy
NON-RENEWABLE
Limited
o Take millions of years to get replenished Examples: Fossil fuels (coal, oil & natural gas) Nuclear power (using uranium)
•
RENEWABLE
• Can be used over and over again
Can be replenished in short period of time Examples: Biofuels e.g.: bioethanoi, biogas (methane), biodiesel, and wood. • Geothermal power • Hydroelectric power • Tidal power • Wave power • Solar power • Wind power
Wind power
Wind turbines have shafts (blades) that rotate due to wind.
Gearbox maximizes the rotation of the shaft.
Brakes slow down or stop the rotor in very windy conditions,
preventing damage to the blade.
As the turbine rotates, it turns the generator which produces
electricity.
Advantages
o Doesn’t produce Carbon Dioxide so doesn’t contribute to global warming.
o Renewable.
o No waste material produced.
o Cheap running cost.
Disadvantage
Only certain locations are suitable.
o Generation of electricity is weather dependent.
。 Uses a large area (visual pollution).
。 Noise pollution.
o Turbines are expensive to manufacture.
o Turbines can threaten or kill wildlife birds.
o Turbines have to be shut down if there is too
much wind.
Why do some countries refuse to invest in renewable sources
Expensive due to prices of new power plants, factories, and machines.
- Current contracts with oil companies.
- Less energy yielded from renewable energy resources.
- Renewable resources may not be constant.
- Countries may not have suitable sites to yield a type of renewable resource.
- (Public opposition to change and some countries do not think pollution issue is a priority.
- Some countries are rich in fossil fuel.
Tidal power
Uses the natural rise and fall in the level of water in an area.
When the levels drop, water is held back by a tidal barrage (a small dam that releases water back through a turbine that turns the generator to generate electricity).
Advantages
o Renewable
Doesn’t produce Carbon Dioxide so doesn’t contribute to global warming.
o Tidal movements are not weather-
dependent.
o Low running cost
Disadvantage
Limited to specific Coastal areas.
Impact on tourism and local fishermen.
Disrupts food chain causing habitat loss.
Increases siltation so less photosynthesis
causing habitat loss.
Hydroelectric power
Uses a dam on a river to store water in a reservoir.
Water is released from the reservoir that flows through the turbine, rotating it.
The turbine then activates a generator that generates electricity.
When the electricity is not needed it is used to pump the water from the lower reservoir to the upper reservoir.
Advantages
Doesn’t produce Carbon Dioxide so doesn’t Contribute to global warming.Renewable (water can be reused). Employment opportunities at the power stations .
Disadvantages
Dams impact the natural flow of water.
Villages and ecosystem may be destroyed. Loss of farmland so loss of employment.
o Towns or villages may need to be relocated.
Negative impact on aquatic life
→ needs Suitable weather
Wave power
Wave Power:
Also uses turbine and generator.
Uses the smaller differences in water levels that are caused by wind.
Advantages
o Doesn’t produce Carbon Dioxide So
Wave Power
doesn’t contribute to global warming.
o Renewable.
Disadvantages
o Limited to specific areas.
o Not very efficient at present.
weather dependent
Fossil fuels
Fossil Fuels (coal, oil, and natural gas):
These Produce massive amounts of energy during combustion that is used to heat water and Convert it into steam. The steam drives the turbine that turns the generator to convert mechanical energy into electrical energy to generate electricity.
Advantages
Plentiful supply
Provide job opportunities (mining and processing) The technology used is well known and the methods of extraction are well practiced. Coal is the cheapest source of fossil fuel Coal is easy to store. Oil as a liquid it can be easily pumped, transported, piped and its widely available
Disadvantages
0 Non-Renewable 0 Damages local areas
o Carbon Dioxide and toxic gases are released when burnt so contributes to global warming. Some fossil fuels like coal produce sulphur/ SO2 emission which contributes to acid rain. Risk of oil spills
