Increasing Energy Security Flashcards
Use of fossil fuels
In 2014, 81% of the energy used worldwide came from fossil fuels. As fossil fuel reserves are depleted, their prices rise, and it becomes more economically viable to develop less accessible reserves.
Hydraulic Fracturing
Hydraulic fracturing (‘fracking’) is designed to extract natural gas from shale. High-pressure fluid is pumped into rock, causing it to crack and release gas, which can then be collected. However, fracking is controversial- it may cause environmental issues such as groundwater contamination and air pollution.
Tar sands
Oil can be extracted from tar sands-sediment that contains bitumen (low-grade oil) - by mining the sediment then separating the oil from it. It takes about 2 tonnes of tar sand to make one barrel of oil, so mining is large-scale and has major environmental impacts.
Nuclear power
A lot of nuclear energy can be generated from a very small amount of fuel, and nuclear power has low CO, emissions. However, disposing of waste can be difficult (see next page), and accidents (e.g. leaks of radioactive material) have devastating impacts on people and the environment.
China and Russia-Nuclear power
China and Russia, are planning new nuclear power plants, and the International Energy Agency suggests that doubling global nuclear energy production by 2050 would help limit climate change.
Renewable resources
Developing renewable energy resources, such as solar, wind and biomass, decreases reliance on fossil fuels and increases energy security. For example, the Three Gorges Dam in China has a generation capacity of more than 20 000 megawatts of hydroelectric energy.
Disadvantages of renewable resources
They are expensive to develop and can be unreliable (e.g. wind turbines don’t generate power on a still day). Some schemes caused other problems, e.g. the Three Gorges Dam project involved flooding 632 km² of land, which displaced over 1 million people.
Buildings can be adapted to reduce their energy consumption, For example:
Installing double glazing and insulation and using energy-efficient building materials helps reduce heat loss.
Building in features that help absorb and retain the Sun’s energy (e.g. large, south-facing windows) reduces the need for artificial light and heat, and low-carbon technologies such as solar panels can help provide electricity.
Installing energy-efficient boilers and other energy-saving appliances reduces electricity use.
Changes to transport can also reduce fuel usage. For example:
Governments can reduce car use by improving public transport, e.g. increasing bus services or building new park-and-ride schemes. They can also encourage people to walk or cycle, e.g. by building more cycle lanes or by introducing schemes to make buying a new bike cheaper (such as the Cycle to Work scheme).
Governments can also discourage car use by penalising drivers, e.g. using congestion charging or road tax.
Acid rain
Burning fossil fuels releases various gases. Some of these dissolve in water vapour acid rain and the enhanced in the atmosphere, which then falls as acid rain. Acid rain reduces sustainability by:
Killing fish and other aquatic life, which can lead to reduced biodiversity.
Killing trees and other plant life, which also reduces biodiversity.
Reducing the nutrient content of soil so that some species of plants can’t grow, or grow more slowly.
Corroding rocks, e.g. limestone and sandstone, including buildings.
Enhanced Greenhouse effect
The greenhouse effect is where greenhouse gases such as CO2 and methane in the Earth’s atmosphere absorb outgoing solar radiation, so less is lost to space. This keeps the Earth at a habitable temperature.
What causes the enhanced greenhouse effect
Burning fossil fuels releases more greenhouse gases into the air. This is unsustainable, as it enhances Earth’s natural greenhouse effect, increasing global temperatures and causing other changes to climate (e.g. changing rainfall patterns). This could lead to:
Rising sea levels and increased flooding.
More frequent and severe extreme weather events, e.g. hurricanes, droughts.
Habitat loss (which leads to loss of biodiversity and the extinction of species). Changing patterns of agriculture-e.g. reduced rainfall in Africa and Australia could decrease agricultural productivity.
Decreases in water availability in some areas, which could cause conflict
Nuclear waste
High-level nuclear waste has to be stored carefully for thousands of years- if it leaks into the environment it can have devastating and long-lasting consequences, eg. contamination of large areas of land, and human, animal and plant deaths and illnesses.
Nuclear waste- environmental impacts
Many people believe that the best way to dispose of nuclear waste is to bury it deep underground. However, this is very expensive-some countries do not yet have enough waste to make it economically viable to create geological storage facilities. It also raises objections from environmental groups and people living near proposed sites, who are worried about the long-term effects (e.g. on health, the environment and tourism) of transporting radioactive material to the area and storing it there.
Nuclear waste- Storage
No deep underground stores like this are in use yet-most countries currently store used nuclear fuel in temporary facilities above ground, which is not sustainable in the long term. However, some countries have started building permanent stores, e.g. Finland.
