Energy can be non-renewable or renewable.
Non-renewable resources (aka STOCK): resources which are FINITE, once they have been used they cannot be replaced. They also have a major environmental impact as they involve the burning of fossil fuels which contain hydrocarbons & release harmful gases like co2 and so2 when burned. E.g. Coal (fossil fuel), oil (ff), natural gas (ff), petrol, copper.
Renewable resources (aka FLOW): Potentially INFINITE (if used in a sustainable way). This type of energy can be replenished at a similar rate to which it's used. They're less harmful to the atmosphere and generally do not require destructive/dangerous extraction methods. They're "cleaner" sources of energy. They may be expensive to develop byt cheap to operate. E.g. bioful, solar panels, hydropower (running water electricity), wind turbines, biomass (cow poo etc)
Some resources are only renewable if managed carefully. Whether a resource is renewable or not depends on how fast the resource is being used compared to how fast it's being replaced/replenished. It the rates are roughly equal then it's renewable.
Fuelwood - RENEWABLE. If areas like forests have the trees chopped down (deforestation) the trees will all be gone, it can be avoided however if afforestation takes place. (E.g. plant 3 for every 1 chopped down)
Nuclear fuel - NON RENEWABLE. It comes from radioactive substances like uranium, plutonium etc. So uranium needed to provide energy, there's only a limited supply of it so once it's used up more energy from this source can't be produced.
Some renewables are classed as FLOW resources and others are classed as CONTINUOUS resources.
Flow resources - need to be managed sustainably to ensure that the use of the resource doesn't outstrip the rate of replacement. E.g. running river water (resovoir - must be replaced), trees.
Continuous resources are always there and being continually formed. E.g. solar energy, rainfall, wind and tidal waves.
Coal - Formed from swamp forests which grew in carboniferous times.
Natural gas - Given off as oil forms.
Oil - Formed from the remainds of microscopic sea creatures trapped in sediment.
Energy sources can be subdivided into 2 categories - PRIMARY energy & SECONDARY energy.
Primary energy - Resources are raw materials used for power in their natural form to produce heat/power. E.g. burning coal directly releases heat which can be used to cook on. It is energy that's released from a direct source. E.g. coal, oil, wood, uranium.
Secondary energy - Resources don't exist in nature. Primary energy resources are converted into secondary energy. They are important because they are easier to use than the primary energy resources. E.g. when heat energy from burning coal is converted into electricity. Another example is petrol which is converted from oil. E.g. petrol, diesel, electricity.
Greenhouse gases are:
CO2 (Carbon Dioxide)
NOX (Nitrogen Oxide)
Fossil fuel: A natural fuel such as coal or gas, formed millions of years ago from remains of living organisms.
Energy mix of Mali
Energy mix - looks at the amount and type of energy used in a country (by households, industry and business) for electricity generation.
Mali's energy mix:
- Oil and coal (imported) 9.9%
- Fueldwood and charcoal 90%
- Renewable and others 0.1%
Location of Mali: West Africa. In the Sahel, a region threatened by dought and desertification. Norther 65% of the country is a desert or semi desert.
- 90% of Mali's energy is from fueldwood - plenty of trees
- No fossil fuel reserves so need to import
- Less than 2% people have electricity (in rural areas) so use fueldwood
- Fueldwood is cheap
- Can't afford to import more coal and oil. Being a landlocked country increases transportation costs.
- Solar energy is plentiful (near Sahel Desert) but the technology is too expensive to develop
Energy mix of UK
UK's energy mix:
- Renewables 3%
- Nuclear 8%
- Coal 15%
- Oil 33% 3/4 is oil & gas
- 41% gas
- 89% is fossil fuelds (mainly oil & gas)
Reasons for UK's energy mix
- Cheaper to import coal from South Africa & Australia
- Goverment wants to increase renewables & nuclear in order to cut greenhouse gas emissions & has targets (Kyoto Protocol -enforced in 1997) of 30% renewables by 2020.
- Use of renewables & nuclear will increase in the fututre as they don't emit harmful hases into the atmosphere.
- Over the last 20 yrs our usage of coal has decreased and oil & gas have increased as they emit less air pollutants.
- Coal emits a lot of greenhouse gases.
- Coal in UK is deep so expensive to extract
- UK has reserves of oil & gas in the North Sea. It's use has increased since its discovery in 1969.
- Only 30 years of reserves left in Northern Sea.
Comparison of UK's energy mix & Mali's
The UK's energy mix has developed gradually over time and at present is still going through a period of change.
3 differences between energy mix of UK and Mali:
- 90% of Mali's energy mix is from fuelwood whereas for UK 3/4 is from oil & gas.
- Mali is an LEDC, landlocked so transporting coal and oil is expensive. UK is an MEDC and has oil and gas reserves in the North Sea.
- Less than 2% of people in Mali (rural area) have electricity so use fuelwood whereas everyone in the UK has electricity.
Why's it better to have a range of energy sources like UK compared to reliance on one source like Mali?
- More sustainable
- If one runs out there's alternatives
- One may be better than the other
Energy mix of UK
Use of oil & gas in the UK.
- Currently oil contributes towards 1/3 of the UK's primary energy mix.
- UK is still the largest producer of oil and gas in the EU.
- Oil and gas reserces in the North Sea are diminishing, expected to run out in 30 years.
- Over 40% of our primary energy is from natural gas. It's the main energy system in the UK.
- More than 90% of Britain's gas comes from the North Sea.
- Approx. 10% is imported via the European gas network (with 2% of this from Russia)
Advantages & disadvantages of gas-fired power stations
- Gas fired power stations release 40% less CO2 than coal fired stations. CO2 is a greenhous gas which contributes to global warming.
- Gas is seen as being relatively clean and pollution free.
- Gas reserves in the UK may run out within 30 yrs, whereas there are proven coal reserves for 300 years.
- Modern gas fired power stations produce very little SO2 and only 1/5th of the NO2 produced by coal fired stations. These gases are associated with acid rain (deposition).
There's significant reserves of Shale gas in the UK (e.g. Lancashire alone could hold 10x more gas than current reserves in the North Sea) which could transform the future for the UK energy mix. Fracking is the process by which gas is extracted from the ground, it involves drilling down to the shale rock and injecting water and gas at high pressure into the rocks which would fracture it, and then this would release the gas.
Problems with fracking & using Shale gas
- Groundwater contamination
- Risks to air quality
- Migration of gases & hydraulic fracturing chemicals to the surface
- Mishandling waste
- Raised CO2 levels
- Flaming taps - water from the tap has CH4 which burns (flammable)
- Minor earthquakes
Use of coal in the UK
"King Coal" was a phrase which highlighted the importance of coal during the Industrial Revolution. Until about the 1950's, coal was the UK's primary energy source because it was easily accessible from numerous British coalfields. Coal has decreased in importance is now less than 1/5th of our primary energy mix.
Decline of coal was because between 1923 & 1945 employment in mining went from 1.2 to 0.8 million. British share of coal marker dropped from 59% to 37%.
There are still large reserves of coal, but imports of coal are rising. At present many mines are not thought to be economically viable due to deep seams, the coal having a high sulphur content (Causing acid rain) and cheaper coal being imported from Australia and South Africa.
The future of coal
Coal industry in the UK may be on point of a limited comeback with the development of 'clean coal technologies' which involve using various methods so that coal is burnt without emitting so much CO2. Exisiting power stations can be upgraded to use clean coal technology. Various methods allow coal to be burnt without emitting so much CO2.
Clean coal technologies
- Burning coal releases CO2 which is a greenhouse gas. Carbon capture involves capturing CO2 and storing it deep in the ocean/underground. E.g. pumping the gas into disused coalfields or into the oil fields in the North Sea.
- Coal can be washed to remove any impurities (e.g. sutt) so it will burn more efficiently.
- Burning coal releases SO2 which causes acidic deposition/acidic rain. A mixture of limestone and water can be sprayed over this flue gas and this reacts to form calcium carbonate (gypsum) which is removed and used in the construction industry.
Use of nuclear in the UK
- Nuclear was developed back in the 1950’s following investment in technological research.
- It grew rapidly in the 1960’s and the 1970’s, but environmental pressure and fears around safety (particularly following the Chernobyl disaster in the Ukraine in 1986), have caused concerns.
- In 2003, the UK government declared that nuclear power was “an unattractive option for the future".
- In the 2007 White Paper on Energy, the government are now favouring nuclear power expansion, and are supporting the construction.
- of up to 10 new nuclear plants, at a cost of £1.2 billion each, through private investment.
- Currently eight sites across England and Wales have been identified as potentially suitable for new nuclear power stations. A further three sites have been ruled.
Use of nuclear in the UK
Reason associated with the use of oil & gas
- The UK want to reduce their dependency on oil and gas due to the decreasing reserves. The UK has to import oil and gas from other countries such as Russia. This reliance is expensive for the UK. Furthermore, failing to reduce our Carbon emissions from burning oil and gas would fail to comply with the Kyoto Protcol and so the UK would be taxed heavily.
Reasons associate with the use of coal
- UK coal production peaked in 1925 and we still have a lot of reserves but it's not economically viable so we import from other countries.
Reasons associated with the use of renewables
- Renewables would not be sufficient to replace the exisiting electricity generated from Britain's current nuclear stations. This is without the expected increase in nuclear.
Reasons associated with the use of nuclear
- Nuclear power is generated from Uranium which is evenly distributed around the world. Out of this Uranium only very limited amounts are needed (around 50 tonnes per hour)
Use of renewables in the UK
In 2004, renewables accounted for only 2% of the primary energy supply in the UK. The 3 most important forms of renewable energy in the UK are:
- Landfill gas (currently the biggest contibutor to UK's renewable energy)
- Hydro Electric Power (HEP)
Reasons why these contribute for UK's energy mix:
- We have a lot of landfill. Waste decomposes in ground, produces CH4, CH4 captured & used.
- A lot of fast flowing rivers. Resevoirs are contained valleys. Lots of rain.
- UK the the windiest country in Europe & so wind turbines are good to use.
Use of renewables in the UK
By 2020, 30% of the electricity from renewable sources. (Target)
Wind energy is expected to increase in the future in order to meet the goverment targets.
The main focus for reaching the government’s renewable energy target is building more wind farms. Between 3500 and 5000 new wind turbines will be required to reach the targets.
Currently wind is the 3rd biggest contributor to the UK’s renewable energy. However it is set to become the biggest contributor.
Since 2000 biofuels has been the biggest contributor to the UK’s renewable energy & has the potential to make a significant contribution in the future. Most of this energy is generated from landfill gas
HEP is currently the second biggest contributor to the UK’s renewable energy. However, opportunities to increase this in the future are limited as the best sites have already been used. On the other hand, if the energy from all the streams and rivers in the UK could be tapped, it would be possible to produce just over 3% of total energy
Production and consumption of energy
o Most developed countries have coal but the coalfields are not economically viable at present as the coal is in deep seams (e.g. UK). Instead, it is imported from countries where there are vast open-cast mines which allow the coal to be extracted cheaply
o Bulk coal-carrier ships have helped to cut the cost of transporting coal from one continent to another. As a result, coal is now transported around the world.
Coal is more widely available compared to the other fossil fuels. The most coal rich region is in Asia, especially China & India. The coal here is cheap to mine but has high sulphur content. Mosts MEDCs have coal-it was one reason for the Industrial Revolution beginning in these countries – but many coalfields are not economically viable at present (e.g. UK). Other countries which produce lots of coal are Australia and South Africa.
Top 3 countries that produce the most coal:
Production and consumption of energy
- Oil is the most versatile and widely used world energy source. Used as petrol, diesel or kerosene or converted into electricity. It is used to heat homes, factories, move goods (transport) and make a variety of products e.g. plastics, fertilizer.
- Production is dominated by a few countries but consumption is dominated by the wealthiest industrial nations.
- This results in oil being transported long distances by tanker, but there are also numerous short distance pipelines.
Issues associated with transporting oil include:-
– Accidents leading to oil spills e.g. BP in Gulf of Mexico (2010)
– On land oil pipelines must be well maintained to reduce leaks
– Hijacking of tankers by pirates off the Somali coastline for money.
Production and consumption of energy
70% of Oil reserves are in the Middle East, especially Saudia Arabia which has 25% of the world reserves & are twice as large as Iran’s which has the second largest reserves. There are also significant oil reserves in Russia & the USA which produces a large amount of its own oil e.g. from Prudhoe Bay in Alaska.
Top 3 countries that produce the most oil
- Saudia Arabia
OPEC is the Organisation of Petroleum Exporting Countries. It is an organisation of 12 countries which have the majority of oil reserves and control over 1/3rd of world production. They use a system of output quotas to control oil production and oil prices. OPEC aims to keep the price of oil high by restricting their own production and agreeing high prices amongst themselves to gain maximum income. They raised the oil price twice in the 1970s leading to economic problems in importing countries like the USA.
Production and consumption of energy
Reserves of gas are widely dispersed. Gas is a very popular fuel because although it is flammable, It can be transported long distances as a liquid - liquefied natural gas (LNG), or over shorter distances via pipeline. It also doesn’t generate as much Carbon dioxide, sulphur dioxide & nitrous oxides as coal burning power stations. Gas reserves are more widely distributed. Russia has the largest reserves, followed by the Middle East.
Top 3 countries that produce the most gas:
The geopolitics of energy
GEOPOLITICS is the study of the political nature of energy supply and demand which can lead to conflict.
This means geopolitics is brought about for several reasons:
- Finite supply of non renewable resources means countries will run out of reserves.
- Reserves are not found in all countries so energy needs to be traded
- World population is increasing leading to increased demand for energy.
- Countries are industrialising such as China and India so industry in these countries
consumes more energy.
- Disputes over price – oil prices have been extremely high since 2006
Conflict over energy supplies
ANWR - Nature reserve with Caribou. USA want to extract oil from ANWR but ANWR doesn't want them to as it's a Caribous breeding site.
Russia's joined with Crimae and so have more oil and gas. But over 1/2 the pipelines go through Ukraine and it could be an issue if Ukraine doesn't allow that. This affects Europe and Russia. They've taken over the black sea of oil and gas.
Oil and gas under the Antarctic ice cap but there are mining bans in place for now to protect the pristine environment. Mining ban will be reviewed in 2040.
The role of Transnational Corporations in the prod
Transnational Corporation/Multinational (TNCs) are companies which operate in more than one country. Their headquarters are usually based in MEDCS. Some of the world’s largest TNCs are oil companies.
World's largest TNC's, 2007
- Rank 2 - Exxon Mobil
- Rank 3 - Royal Dutch/Shell
- Rank 4 - BP
- Rank 7 - Chevron
- Rank 9 - ConocoPhilips
- Rank 10 - Total
TNCs are also involved in the production and distribution of other energy resources – not just oil. For example, the UK Government’s latest plans to construct 10 new nuclear power stations through private investment have attracted the interest of TNCs, such as Shell. The world’s largest oil companies dominate the production and distribution of oil and gas resources at a global scale.
- They have access to the technologies and information which allow them to DISCOVER new
oil reserves and then EXTRACT them
- They have their own pipelines and ships to TRANSPORT oil & gas around the world.
- They have their own REFINERIES at the point of importation, producing a wide range of
fuels and lubricants.
- They also have a large numbers of RETAILS OUTLETS where oil & petrol are sold to the general public
Case Study: Gazprom
Gazprom & the Geopolitics of energy - The Russia/ Ukraine Crisis (January 2009). Russia used to ‘own’ Ukraine as part of the USSR. It has never been friendly to it since it broke away and declared independence in 1992.In the latest dispute, Tens of thousands of Europeans ended up without heating during January 2009.
- Causes of dispute: Ukraine has recently been in dispute with Russia over gas supplies. Gazprom, A Russian company, threatened to raise prices demanding $480 per cubic metre of gas. Ukraine would not pay the increased price & wanted the lower price it had already been paying of $230.
- On 1st January 2009 Russia closed the pipeline to Ukraine.
- Russia accused Ukraine of siphoning off gas meant for European customers.
Consequences of dispute for European countries
- This also affected supplies to the EU, as the pipeline carried 25% of the EU’s gas supply, and caused prices to rise there.
- leaving more than a dozen countries without their expected supplies of Russian gas. European countries had to shut down industrial plants and domestic heating systems, find alternative sources of gas or switch energy plants to oil.
- Schools were shut and people had to revert to using log fires to heat their homes.
- gas prices still rose by 26% as cheeky energy companies used the crisis as an excuse to increase prices.
- UK also exported gas through an interconnector pipeline to continental Europe due to the gas supplies shortages in many countries.
The Russian/Ukraine dispute
Consequences of the dispute for Russia
- USA and UK saying they're going to find an alternative supply of oil and gas - This affects Russia's income.
- 40% of Russian gas goes through the Ukraine.
- EU now want to have alternative for oil and gas from elsewhere.
- Pipeline being planned through central Asia (Nabucco Pipeline)
Consequences of the dispute for European countries
- 40% of gas goes through Ukraine.
- Gas prices rose by 26%.
- Slowakia, Bulgaria, Hungary, Austria & Eastern EU affected most.
- More than a dozen countries didn't have their expected Russian gas.
Russia/Ukraine dispute. Gazprom
Headquarters & country of origin
- Russian oil & gas company.
- Gazprom used to be a Russian ministry before becoming a private company, and it remains very closely connected to the state - Russian President Dmitry Medvedev is a former chairman of the company.
Host countries (who they give to / where they operate)
- Serves 32 countries in total including Russia, Europe, US, Japan and South Korea.
- Provides the EU countries with about 25% of their gas.
- Bulgaria The Bosnia, Slovakia & Hungary are almost 100% dependant on Russia for gas (hence a huge problem for these countries when their supply of gas is cut off)
Roles in energy production and distribution on a global scale
- Russia is one of the world’s biggest oil & gas producers
- Gazprom produces 60% of Russia’s oil & gas
- Russia plans to open new gas pipelines such as Nord Stream and South Stream to bypass Ukraine (avoiding geopolitics) and supply Europe with gas.
- However, the Russian/ Ukraine dispute in January 2009 could result in Russia losing export opportunities & control over distribution of resources with a new pipeline called Nabucco pipeline which will bring gas from Central Asia into the European Union.
Role in energy provision in the UK
- The UK imports only 2% of gas from Russia, but this could rise in the future with the decline in North sea oil.
- North Sea oil & gas are expected to run out in roughly 30 years time.
- The UK plan to diversify their energy mix so they do not have to depend on gas from Russia. They want to increase renewables, nuclear and shale gas (via fracking)
Case study: Shell
Shell and geopolitics of energy
As the 3rd largest TNC in the world, Shell is a true transnational company. It operates in 140 different countries, has over 25 million customers daily, and has a gross income of $175 billion per year (80% from oil and gas sales). This can be put in context by knowing that the average African country has an annual account balance of $10 billion per year (this includes overseas oil). Shell employs 90 thousand people worldwide.
Origins and building a brand
The TNC started life as a small importer of shells, then an importer of oil (from Russia). The company then merged with the Royal Dutch Company to create Royal Dutch Shell Group in 1907 he company grew quickly as it moved into the US market and became a Producing, Refining and Distributing of oil products, finally developing Petrochemcial and Natural Gas industries.
Case study: Shell
Evidence for Shell being an environmentally friendly company
- $13 million to fund sustainable energy and biodiversity.
- Shell foundation promotes renewable energy.
Evidence against Shell being an environmentally friendly company
- Emission from fossil fuels bad for planet.
- Use a lot of oil - unsustainable.
- Ship blew up
- Oil spillages
- Refinery fires
Niger Delta, Nigeria (linked to Shell)
Nigeria - Central Africa (has large oil reserves). These people were affected by Shell's extraction.
Impacts on Ogoni people
- Oil spillages so damaged farmland (their main source of food)
- Oil spills so fish die - can't fish anymore
- Gas flaring (burning off unwanted gas) so respiratory probs and air pollution
- Ogoni people protested and got hung and their bodies were dissolved in acid
- Ogoni land is the most oil polluted land on Earth
- Food source affected as land and rivers are polluted
- Ogoni people are protesting violently now
- International condemnation
Shell's influence of the goverment corruption
- Ken Sara Wiwa was leader of movement of the surival of ogoni people (MOSOP)
- He led peaceful protests against Shell's environmental damage
- Goverment didn't like this as oil is a source of wealth to the country
- Ken Sara Wiwa and 8 other activists arrested in 1995. Hung & bodies dissolved in acid.
Despite the wealth that has been generated in Nigeria as a result of the money and technological resources provided by TNCs such as Shell in extracting and producing the oil, 60% of the population still live in poverty. Shell also makes huge profits from its operations in the country.
Nigerians are impoverished and have had limited benefits from oil wealth
- Goverment corruption is widespread - Siphons off up to 70% of oil revenue.
- 60% of the population still live in poverty.
- Many local people forced to give up fishing and farming due to oil spillages - but find it difficult to get alternative employment.
The Niger Delta is polluted from the production and distribution of oil
- 40% of Shell's oil spills worldwide have occured in the Niger Delta.
- Over 4000 oil spliis have occured since 1960.
- Oil pollution in water is more than 60 times the US limit.
- 75% of total gas production in Nigeria is flared.
Environmental impact of energy production
The impact of oil exploration e.g. in ANWR (Alaskan National Wildlife Reserve)
ANWR is an example of a wilderness area.
This is an area where there's a diverse species of animals, an unspoilt area available for habitats, migrating etc.
What could be the environmental impacts of oil drilling in this area?
- Caribou reproducing grounds affected
- Loss of habitats
- Disturbing animals
- Oil spills
- Landscape becomes industrialised
- 50 years for damaged vegetation to recover (due to it being so cold)
The depletion of fossil fuels
- World Oil reserves forecast to last 40 years
- World Gas reserves forecast to last 70 years
- World Coal reserves forecast to last 150 years
When fossil fuels run out or become scarce, what impact will this have on a countries energy mix? – e.g. UK Nearly 89% (3/4) of the UK’s energy mix is fossil fuels. As they become scarce in the UK – may import more (2004 UK became net importer of coal for the first time since 1993) This may cause a problem with geopolitics e.g. if gas is imported from Russia. May also increase renewables e.g. wind energy. Environmental effects of renewable energy: don't release air pollutants but also an eye sore.
The cause (i.e importance of fuelwood collection in Mali)
What % of Mali’s energy mix is from fuelwood? 98%
Why is fuelwood, as a source of energy, so important to Mali?
- It's 98% of their energy mix.
- It's their only source of energy. Too poor to import oil and gas.
- 60% rural & 2% have electricity. They need primary energy.
Why are the forests in Mali disappearing at an alarming rate?
Trees aren't being replaced.
In Mali, women and children bear the burden of fuelwood collection which can take up to 5 hours of daily trips. Many children, especially girls are withdrawn from school to attend this task
The environmental effects of fuelwood collection
• As the wood is not being replanted, it will eventually run out (non-renewable).
• Deforestation leads to soil erosion and desertification.
• The land becomes barren and infertile meaning that future crops cannot be grown. This is because the removal of trees can affect the hydrological cycle in the local area.
Desertification: Is the spread of desert like conditions into neighbouring semi-arid regions of bush, grassland or woodland.
How removal of trees would affect....
Siltation results in soil being washed into the rivers. The muddy water becomes undrinkable. Also soil erosion so silt settles on the river bed.
Becomes dry and so is no longer fertile - can't support any trees. Becomes eroded as no tree roots to bind soil together, so increased soil erosion by wind/runoff/rain - desertification.
The local climate
Less evaporation, less clouds, so less condensation so less rain. Land becomes dry.
The global climate
Trees take in CO2 and release O2. They're a Carbon store. If cut trees the CO2 is released and so more greenhouse gas so increased global temps.
Reducing the environmental effects of fuelwood gat
The Mali Folke Centre (MFC), a Christian Aid partner, has installed solar panels on the roofs of 30 schools. Local people have been trained to maintain them. 99% of rural areas have no access to formal electricity. This scheme provides a sustainable form of energy so helping to reduce dependence on fuelwood for cooking and heating.
MFC has also helped to develop crop plantations of jatropha (a shrub whose seeds contain a high proportion of oil which can be used as a biofuel). Jatropha oil can be used as a replacement for fuelwood for cooking & is also healthier, as cooking is done in a smoke-free environment. Women also do not have to spend time gathering fuelwood. The decreased need for fuelwood also relieves pressure on forest resources.
There is also a project which helps locals to produce fuel briquettes. To make a briquette ordinary leaves, grass and straw are chopped and mashed into a paste which is then compressed into round cakes and dried) An environmentally friendly fuel alternative to fuelwood, made from agricultural by products. They burn for longer and are 25 per cent cheaper than traditional wood based products.
NGOs & the Mali Government have been encouraging women to use more energy efficient stove. Less fuelwood is used during cooking compared to traditional stoves.
Appropriate technology defined..
It is appropriate because the projects use simple technologies which are suitable for use in
LEDCS. Ideally, appropriate technology (compared to more sophisticated technology) involves:-
- fewer resources
- is easier to maintain
- has a low overall cost
- less of an impact on the environment
Another alternative to fuelwood - biogas obtained from dung fermentation, rural India. Alternative strategies which move away from traditional fuelwood usage can be seen in Gujarat, a region of Northwest India. Here, the basic energy shortage demanded that alternative solutions were found, which were APPROPRIATE to the needs of the people.
What is biogas from dung? How does the system work?
1) Cattle produce dung
2) Dung taken to holding tank and mixed with water to form slurry and allowed to ferment
3) Methane (biogas):
- Farmer gets fertiliser
- Villages supplied with CH4 for cooking and lighting so reduces demand for fuelwood
Why is it appropriate technology?
- Using resources they're got. It's cheap, available and easy to maintain.
The hazard of nuclear waste and its management
UK’s entire existing nuclear facilities are expected to be redundant by 2035 (although the life of Sizewell B, built in 1995 may extend beyond this), and that this will leave the UK with a major energy gap. In response, the UK Government has recently announced a swing back to using Nuclear Power as a major source of electricity. New plants are being planned and may be operational by 2017 if the waste management issues can be addressed by the Government.
Arguments against nuclear
- High cost – construction of nuclear plants, decommissioning plant at the end of their life and storage of the waste
- Nuclear waste remains radioactive for 1000s of years, and in some cases millions of years. Health risks associated with radiation exposure e.g. Cancer . Potential to be fatal.
- Risk that Nuclear technology could be used to produce nuclear weapons in some countries e.g. Iran, North Korea.
- Safe and secure storage of waste needed for at least 250,000 years.
Arguments for nuclear
- Increasing nuclear in the UK energy mix will help reduce carbon emissions (target to cut CO2 emissions by 80% by 2050) & so tackle global warming (CO2 is responsible for 60% of the recent global warming)
- Only small amounts of uranium is need to produce nuclear power
- Uranium reserves are evenly distributed globally. Less prone to shortages through conflict
UK want to construct at least 10 nuclear power stations. They don't produce much CO2 and there's not a lot of waste produced.
Largest powerplant in UK: Heysham, Lancashire.
Problems with nuclear energy:
- Disposing of nuclear waste.
- Waste leakages
Sellafields is used for the storage or nuclear waste but also reprocesses waste in the THORAP.
Classification of nuclear waste: Low level, medium & high level waste.
Nuclear power stations produce quantities of radioactive waste as a bi-product of the nuclear reaction. Types of waste range from the uranium rich fuel rods used in the reactor core, to the clothing used by the power station workers.
High-level radioactive waste (HLW)
This is the most dangerous type of radioactive waste. It includes fuel rods which have been used in the reactors. It is disposed of at THORP (Sellafield) in Cumbria and stored in large lead lined glass containers or steel clad containers.
Intermediate Level radioactive waste (ILW)
This is resin and chemical sludge from the nuclear reactor
Low-level radioactive waste (LLW)
This is less radioactive objects that have been briefly exposed to radioactivity. It includes protective clothing worn by workers at the nuclear power station.
Nuclear waste has a long half life (the amount of time it takes to lose half its radioactivity). The waste will therefore remain radioactive for thousands of years. This needs to be considered when disposing of it. Transporting the waste is also a problem.
Radioactive Waste Disposal
Interim (short term) storage of radioactive waste is already in place. 20 surface sites (including Sellafield) currently store the waste. It requires the maintenance of an industrial, regulatory and security infrastructure. This is why indefinite storage is required (long term disposal). Indefinite storages places a burden on future generations. The NDA are responsible for the management of nuclear waste in the UK (Nuclear Decommissioning Authority).
Currently geological disposal facility is being considered as an indefinite storage solution.
These are deep underground storage area (at least 1km underground)
HLW and ILW will need turned into glass (vitified) and put in a steel container
Transported by road, rail & sea to a geological disposal facility
Stored in two vaults – one for ILW and the other for HLW
The shafts and tunnels can be backfilled and sealed when full
The British Geological society will choose the best location for a disposal site.
Geological disposal facility
Factirs that could affect it
Rock type - should be impermeable.
Ground water supplies - Well away from ground water supply in a dry area.
Land use - Can't do it where there's farmland.
Population density - Low population density. Secret location to hide from terrorists.
Long term management of waste
Disposal at sea
Positive: Away from human activity. Negative: Banned by international agreement. Cause marine seawater pollution and bad for fish.
Disposal in space
Positive: Removes permanently from environment. Negative: Volume of waste means that a large no. of launches needed increasing chances of an accident (for manking & environment)
Disposal at subduction zones (where Earth's plates are descending into the mantle) Plate boundaries where one plate goes under another.
Positive: Isolated from environment. Negative: Banned because there's volcanoes too.
Disposal in ice sheets
Positive: Could be placed in stable ice sheets (Iceland & Greenland), containers melt ice sheet and are drawn deep in so isolated from human environment. Negative: No suitable ice sheets in UK + process banned by international treaties.
Exporting waste abrod
Positive: Rid of the waste-away from us. Negative: Unethical to burden other countries with our waste.
Transporting Nuclear Waste
Nuclear waste is transported by rail, road and ship. Robust and secure containers are used to transport the material. There has never been an accident whilst nuclear waste has been in transport. HLW packages have shielding from the radioactive rays. The waste is put in a glass matrix (vitrified), this glass is then poured into a stainless steel canister, cooled and solidifies. They are then put in a cask and transported.
Nuclear Disasters Finally, nuclear disasters such as the one in March 2011 in North East Japan at Fukushima nuclear power plant, where the tsunami caused near meltdown of the reactor. Radioactive particles were released into the atmosphere, causing concern over health and crops also had radioactivity detected in them. The radioactive particles were detected as far as Glasgow.
- UV radiation give out from the Sun's rays
- Infrared radiation reflected from the Earth
- Earth couldn't support life without the natural greenhouse affect because it'd be too cold (30 degrees colder than now)
Enhanced greenhouse effect:
1) UV radiation emitted to atmosphere - some rays are emitted back to space as IR radiation.
2) Atmosphere traps heat in the form of IR radiation and warms Earth. Some is sent back to space.
3) Atmosphere is trapping more heat due to more gases, increasing temps therefore.
How's the production adding to the greenhouse gases in the atmosphere?
More fossil fuels are burnt so emit more CO2 and NO2 into the atmosphere. In power plants to make electricity. And from transport and a small amount from fuelwood gathering.
Environmental effects of global warming
Rising temperature would melt snow and ice which would cause sea level rise. However, climatic change may not be even throughout the world.
a) 3 regions that might have warmed most by 2100: Parts of South America, South Africa, Europe
b) 3 areas that may be wetter by 2100: Indonesia, Malaysia, South American countries
c) 3 areas that may be drier by 2100: Australia & parts of Africa.
Responses to global warming
Nothing can be done to stop global warming, but action can be taken to slow it down in the future. This relies on international action, which is difficult to achieve. The Kyoto agreement, signed by many MEDCs in 1997 was an important step towards reducing greenhouse gas emissions. The British government are now taking action to cut carbon dioxide emissions by:-
Responses to global warming
Using less coal and oil to generate electricity and using natural gas , renewable energy and nuclear instead. Persuading people to conserve energy in the home (e.g. insulating the house,turn lights off etc.), in the workplace (e.g. Tesco has policies in place to save energy & reduce vehicle emissions) and in transport (e.g. hybrid cars, improving public transport, congestion zone in London etc)
Acid deposition (an environmental impact of fossil fuel use)
- Sulphur dioxide and nitrogen oxide are released during the burning of fossil fuels in power stations, and from vehicles.
- However in the atmosphere, water and oxygen in the atmosphere to cause acid deposition
- Wet deposition (commonly known as acid rain) is carried over long distances by wind. It is rain, sleet, snow, or fog that has become more acidic than normal.
- Dry deposition is another form of acid deposition which falls closer to the source of pollution. It is when gases and dust particles become acidic.
Acid rain can be reduced by reducing the pollutants from power stations and from vehicles.