7.1 - Energy Choice And Security Flashcards
What do fossil fuels include
- coal
- natural gases
- crude oil
How are fossil fuels formed
Fossil fuels are formed from the remains of plants and animals
- Chemical energy stored in fossil fuels originally came from sunlight
- Energy from the sun was transferred to chemical energy stores within plants through photosynthesis (plants use energy from sunlight to make food)
- Animals ate the plants and the energy was then transferred to their chemical store
What are 3 advantages of fossil fuels
- The current systems of transport and electricity generation used by human societies rely heavily on fossil fuels, which are generally readily available on a daily basis
- In the past fossil fuels have been reliable for large scale energy production (although this is changing as supplies deplete and prices rise)
- Efficient - fossil fuels typically have a high energy density (they produce a large amount of energy per kilogram)
What are 6 disadvantages of fossil fuels
- takes millions of years to form
- the increasing demand for a decreasing supply cause process to increase
- burning fossil fuels pollutes the atmosphere with harmful gases
- oil spills
- prices fluctuate
- supplies can be affected by conflict and political disagreements
What are the 3 main uses of fossil fuels
- transport
- generating electricity
- heating
How is population growth affecting energy demand
- The higher demand for food leads to more intensive farming, which requires more energy for machines, light and heat
- Increasing industry requires energy for heating, lighting and machinery
- There is more transport all of which requires energy in the form of petrol, diesel or electricity
- Urbanisation increases with the development increasing domestic appliances, heating, lighting
- Increased wealth means people buy more appliances and technology which require energy
What are renewable energy sources
Sources of energy with lower carbon dioxide emissions than fossil fuels include renewable energy sources
What are examples of renewable energy sources
- Solar
- Biomass
- Hydropower
- Wind
- Wave and tidal
- Geothermal
What do renewable energy sources not produce
Greenhouse emissions, however the process of creating the equipment to use these resources may produce this energy
What are examples of renewable energy sources
- Solar
- Biomass
- Hydropower
- Wind
- Wave and tidal
- Geothermal
- Nuclear
What are solar of panels
Solar photovoltaic (PV) panels transfer energy from sunlight electrically producing a current, and therefore generating electrical power
- Solar cells, sometimes called photovoltaic cells, are made of semiconducting materials
- A number of photovoltaic cells or panels connected together can supply electricity to homes, small-scale businesses, communication devices and satellites
- Energy generated can be stored in batteries for later use
What are some advantages of solar Pv panels
- Solar energy is a renewable resource
- In many places on Earth sunlight is a reliable energy resource (this means that the sun shines most of the time)
- Solar farms produce no greenhouse gases or pollution
- Solar energy can be generated in remote places where they don’t have electricity (e.g. to power solar street signs in rural areas)
- Can be small or large scale
- Can be incorporated into building design
- Technology is improving and reducing the cost
What are the disadvantages of solar PV
- Solar farms need to be large scale to produce large amounts of electricity, which is expensive to set up
- Uses large areas of land
- People often don’t like the appearance of large solar farms, this is known as visual pollution
- In many places on Earth sunlight is not a reliable energy resource (there are not enough sunshine-hours to justify the set-up costs)
What are solar thermal panels
Solar thermal panels transfer energy from sunlight to the thermal store of the solar panels which is used to heat water in the pipes
- Solar panels can be used to warm domestic water supplies
- This can reduce the cost of producing hot water since it is heated partially by solar panels
What are advantages of solar thermal panels
- Solar energy is a renewable resource
- In many places on Earth sunlight is a reliable energy resource (this means that the sun shines most of the time)
- Solar thermal panels produce no greenhouse gases or pollution once they are operating
- Solar thermal panels can cut the cost of energy bills for households
What are the disadvantages of solar panels
- Additional energy (e.g. from fossil fuels) is still needed to heat water to a higher temperature in domestic households
- In many places on Earth sunlight is not a reliable energy resource (the sun doesn’t shine regularly enough to justify the set-up costs)
What is biomass
Biofuels (also known as biomass fuels) are renewable fuels derived from organic materials, such as plants and animal waste, that can be used as an alternative to fossil fuels.
What are the 3 main biofuels
- Biodiesel - made by refining renewable fats and oils (e.g. vegetable oils, animal fats, or recycled cooking oil)
- Bioethanol - made by fermentation (of crops rich in sugars or starches, such as corn or sugarcane)
- Biogas - released when organic waste products decompose
What are the advantages of biofuels
- Biofuel is a renewable resource - uses waste or bioproducts that can be regrown
- Some vehicles can be powered by biofuel rather than using fossil fuels
- Biofuel is considered to be carbon neutral
No sulfur dioxide is produced
What are the disadvantages of biofuels
- Crops of biofuel producing plants must be grown which takes time
- Growing the crops takes a lot of land, and takes resources needed for food production
- Burning biofuels releases carbon dioxide into the atmosphere (however, it is considered carbon neutral because plants take in carbon dioxide when they photosynthesise)
What is hydropower
- When water is stored above ground level it has gravitational potential energy
- This energy can be transferred to kinetic energy if the water is allowed to flow down the slope
- Flowing water turns the turbine to generate electricity
What are the advantages of hydropower
- Can respond to demand quickly so is reliable and available
- Can generate large scale amounts of electricity in a short period of time
- Often in sparsely populated areas