Coal

Formation:
• Formed from plant or animal material buried millions of years ago
• Anaerobic conditions
• As it is buried there is increased pressure and heat

Types:
• Older deposits are generally more useful
• Older coal has a higher carbon and energy content

• Lignite (brown coal):
 - sedimentary
 - limited supplies in most areas
 - low sulfur content
 - low heat content

• Bituminous (soft coal):
 - sedimentary
 - extensively used
 - high sulfur content
 - high heat content
 - large supplies

• Anthracite (hard coal):
 - limitied supplies in most areas
 - low sulfur content
 - metamorphic
 - high heat content
 - highly desrirable


Uses:
• China is the worlds largest user of coal, followed by the USA
• China has 11% of world reserves
• Used to generate 62% of the worlds electricity
• Electricity generation
• Iron and steel industry
• Provides about 22% of the commercial energy used in the world and the US
• Used to generate 75% of the worlds steel
• Countries getting more than 1/2 of the energy they use from coal:
 - South Africa - 78%
 - China - 73%
 - Poland - 68%
 - India - 57%
 - Kazakstan - 54%


Environmental Impact:

•Extraction:
 •Open cast:
 - Noise pollution
 - Habitat destruction
 - Dust
 - Cannot access deeper deposits
 - Highly mechanised = cheap

 •Shaft mining:
 - Cave ins
 - Flooding
 - Gas leaks
 - Noise/dust pollution

•Air pollution from transportation

•Use:
 • Contains lots of sulphur:
 - acid rain
 - dissolves buildings - limestone
 - destroys trees
 - sent massive cloud of sulphur over to Norway

•Coal fired power stations:
 - UK releases 5-10 million tonnes of CO2 every year
 - Particals of toxic mercury
- 60,000 babies a year may be born with neurological damage from exposure to mercury in pregnant women


Future:

• Coal liquefaction or gasification
• World consumption is expected to increase by 49% from 2006 to 2030
• Scrubbers to reduce CO2 and particulates
• Most growth in NICs
• Moves to clean coal technology could increase even in the developed world
• CCT - treat it and wash it, turn it into a gas then burn the gas which is cleaner than the coal
• Worlds most abundant fossil fuel
• World identified reserves  of coal should last at least 225 years at current usage rate
• 65 years left of coal if usage rises 2% per year
• identified US coal reserves should last 300 years at current consumption rate
• China has 11% of world reserves which will last 300 years at current consumption rate
• Resources at the moment could become reserves as more technically becomes available
• US FutureGen programme - $1 billion - demonstrates commercial viability of near zero emission coal fuelled power
• Japan, Australia and Europe all have their own Clean Coal Technology programmes
• Carbon capture/sequestration

Energy Development

Fire
Animal power
Water power
Wind power
Fossil Fuels
Electricity

Fire:
• allowed the processing of materials - baking of clay to make pottery
• This pottery was then used as a storage for surplus grain which reduced the amount of time searching for food in shortages
• This time which was gained could be used making tools or weaving clothes
• It could also be used to clear woodland for farmland quickly or move animals

Animals:
• They replaced humans in ploughing, carrying goods and driving machinery
• This gives them more time

Wind and water power:
• These were used to drive machinery for grinding, spinning and weaving
• Wind power could be used to propel ships and pump water
• Wind power also allowed sailing so this allowed countries to trade

Smelting:
• Smelting of metals using wood and charcoal allowed useful items to be made - cutting blades, nails, wheel rims and plough
• Smelting of steel was created using coal and coke - this created sophisticated machinery - steam engines
• Coal could be transported wherever it was needed

Crude oil:
• This has increased the amount of energy available - almost all tasks performed more easily

Electricity:
• This can be used to drive more equipment than could be driven by just primary energy

Energy Definitions

Renewable resources: A resource that is reformed by natural processes fast enough for new supplies to become available within a human lifespan.

Energy density: The amount of energy in a particular mass of fuel or that can be harnessed by a particular mass of equipment

Finite resources: Resources where the total amount available is fixed

Wind, solar: Renewable resources that can never be depleted and which are reformed instantly

Wood: A renewable resource that can be depleted

Secondary fuel: An energy that is produced by converting a primary fuel

Peak Shavings: The process of storing surplus energy to satisfy later demand peaks

Deplete: To reduce the amount of a resource that is available

Non- Renewable resources: A resource that is renewed so slowly that the amount available is effectively finite.

Unreliable: An energy resource where the amount of energy available cannot be predicted

Intermittent: The word used to describe an energy resource that is not available all the time

Tidal: An energy resource that is intermittent but very reliable

Wind: An energy resource that is both unreliable and intermittent

Nuclear (Uranium): A very dense energy resource

Government Subsidy: Money made available by the government to for example promote a particular energy resource such as nuclear power in France

Energy Mix: The combination of energy resources used by a country

Reserve: The total amount of material that is exploitable given current prices and technology

Resource: The total amount of a material that is potentially exploitable now or in the future

Hormonal Growth Control

Plant Growth:

•Auxins - help vegetative propagation - stimulates root growth

•Gibberlins - shoot growth - used on cereals to produce shorter stems
 - stimulate seed germnination
 - root growth
 - increase fruit size

•Ethane or Ethylene - stimulates the ripening of fruit


Animal growth:

•BST - increases milk yield in dairy cattle
 - banned in many countries due to risks to human health

•Anabolic Steroid Hormones
 - based on steroid sex hormones
 - increases growth rate and gross growth efficiency
 - if residues of the steroid remain in meat eaten by humans it could affect human growth