Energy Resources

Energy cannot…

Be created or destroyed it can only be converted from one form to another

Watts are the measure of..

The amount of energy per unit time

Watts conversions

1- kilowatts

2- megawatts

3- gigawatts

4- x1000

5- /1000

Joules conversions

1- kilojoules

2-mega joules

3- gigajoules

4- x1000

5- /1000

Conversions between joules and watts

Watts= joules/seconds

Joules= watts x seconds

Seconds = joules /watts

Tonnes conversions

1-kilo tonnes

2- megatonnes

3- gigatonnes

4- x1000

5- /1000

Energy uses in agriculture

Making fertilisers/pesticides and applying them to fields

Fossil fuels used to run large machinery eg tractors

Pumping of water in irrigation

Electricity used for lighting and heating in barns

Energy uses in fishing

Fossil fuels used to power boat engines

Making fishing equipment such as nets

Freezing/keeping stock cold while on board the ship

Energy uses in transport

Fossil fuels used in vehicle engines such as trains, cars, buses, aeroplanes

Manufacturing vehicles and infrastructure associated eg roads/train tracks

Lighting and traffic signals

Electric cars -generate electricity and make batteries

Energy uses in mining

Blast overburden and create the mine site

Extracting the mineral using heavy machinery eg fossil fuels in engines

Smelting to separate minerals

Primary fuel

A natural source of energy which can be used without conversion eg coal

Secondary fuel

A fuel made from a primary fuel eg petrol made from crude oil, as well as electricity, energy is usually lost because of conversion

Per capita

Per person/ population

Equation= total energy used/population

Factors that effect a countries per capita energy consumption

Affluence

Relative cost of energy

Type of industry

Social and environmental awareness of a country

Climate

Affluence

How wealthy a country is on average,

often the more wealth a country has the more energy they use in households through appliances such as dishwashers, washing machines etc

Although some wealthy countries have a greater environmental awareness and invest more money into reducing energy use eg greener public transport

Relative cost of energy

Impacts how much a country uses on average, if energy prices are extremely high, then it’s possible less energy will be used and vice versa

In some countries fossil fuels may be much cheaper than renewables so higher proportion of people will use them like coal oil and gas

Type of industry

Will affect how much energy is used on average, a countries main industry can be put into catagories:

Primary industry- extraction/harvesting of raw materials

Secondary Industry- manufacturing of products

Tertiary industry- providing services

Quaternary industry- high technology industries such as research

Type of industry (primary and secondary)

Primary- require a lot of energy for extraction and harvesting of raw materials like mining, fishing, water abstraction and farming

Secondary- Will require energy for manufacturing processes themselves such as heat or electricity

For this reason they both tend to have a higher energy usage than tertiary and quaternary industries

Social and environmental awareness

If a countries population have been educated about the negative impacts of Climate change then they may make a more conscious effort to reduce energy usage by using energy saving appliances for example or utilise public transport

Climate

impacts how much energy population uses for example in hot climates air conditioning units are installed in most buildings which use a lot of energy

In colder climates large amounts of energy are used to heat buildings

Mid latitude areas most likely use the least energy as they won’t require constant heating/cooling because of moderate temperatures

Why could the energy usage of a country change?

Global climate change- causes warmer temps leading to more AC and water required in farming for irrigation

Industrialisation- if a country becomes a secondary industry than their energy usage may increase however if they move from secondary to tertiary energy usage may decrease

Population growth- more people = more energy use

New technology development- new car designs such as hydrogen may reduce reliance on fossil fuels in the future

Changes to Domestic gross product (DGP)- if the country’s economy is doing well then affluence will increase

Changes in environmental awareness- people may become more environmentally aware overtime leading to a conscious effort to reduce energy usage or vice versa

Case study for economically stable/less stable country for energy usage

Countries such as Brazil china and India have industrialised a their use of energy has increased rapidly especially mining and manufacturing industries while this activity has declined in the UK so industrial energy use has reduced

Properties of energy resources non renewable vs renewable

Renewable energy resource- natural resource that reforms fairly quickly so current use does not impact upon future supply eg solar, wind, tidal, geothermal etc

Non renewable energy resource- a resource that doesnt reform at all or reforms so slowly that our current usage rate depletes future usage eg fossil fuels/uranium

Properties of energy resources depletable vs non depletable

Depletable- a resource that’s supply can be depleted if used at a rate higher than the maximum sustainable yield eg we may run out completely eg fossil fuels/wood

Non depletable- a resource that’s supply cannot be depleted and we shouldn’t be able to run out completely eg solar power

Maximum sustainable yield- maximum harvest/use without depleting future supplies

Properties of energy resources abundance

The amount of energy resource that exists including the amount we could use and the amount we arent able to use, with some resources we can’t harvest all available energy for example:

solar energy may be reflected by clouds

, wind energy can only be harnessed at the height of wind turbines,

Some fossil fuels are too deep underground or under Antarctica where they can’t be extracted

Wave power- hard to harness energy from waves that arent close to the coastline

Intermittence is…

A measure of how often the energy resource is available, an energy resource with a low intermittence will always be available for example fossil fuels, as long as we keep extracting them they will always be available and the availability doesn’t change on the day/because of weather

Energy resources with high intermittence such as solar and wind power will not be available all day every day eg solar power can only be harnessed during the day

Predictability is…

A measure of how easy it is to predict when an energy resource will be available

High predictability would include tidal power as we can now accurately predict when high tide and low tide will be each day and therefore when we’ll be able to harness the energy

Solar power has low predictability as weather predictions are constantly changing and factors like cloud cover are almost impossible to predict correctly

Locational contraints of an energy resource

An example of high locational constraints this is geothermal power as it can only be harnessed in a location where there are very hot rocks close to the earths surface which is limited

Wave power also has high locational contracts because it can only be harnessed in coastal regions

A resource with lower locational contraints can be used in a wider range of areas such as use of fossil fuels in vehicle engines

Energy density of energy of energy resources is…

The amount of energy in a given mass of an energy resource

High energy density vs low

Resources with high energy density like coal and oil have a large amount of energy per unit mass whereas resources with a low energy density like solar power have a small amount of energy per unit mass

Having higher energy density increases the usefulness of the resource as less is needed to provide the same amount of energy as a low energy resource which can make it easier to transport

Example of high - nuclear power

Example of low - solar/wind power

Energy density of energy resources (conversions)

Some energy resources need to be converted to other energy forms to increase their usefulness whereas some don’t. This can increase the usefulness of the energy resource as it can convert it to a form used in appliances for example

When harnessing wind power for example we convert heat energy into electrical energy, yet conversions arent 100% efficient so energy will be lost which may reduce usefulness and increase waste

Properties of energy resources (transportation)

In order to reach consumers energy resources will have to be transported in one form or another so being easy to transport will increase their usefulness

The ease at which it’s transported depends on lots of properties such as state of matter (solid liquid gas) and energy density (higher density products require a lower volume to carry)

Environmental factors and impacts to consider with each energy resource

Environmental impacts caused from production/extraction of energy resource before use, while being used and at the end of its life such as how it will be disposed of

Technological development available for the energy resource

Some energy resources like fossil fuels have had lots of money invested to increase supplies and usability so technological development is high

For some renewables such as wave and tidal power there hasn’t been much investment so technological development is fairly low which reduces the usability of the resources

Government assistance

Some governments provide grants and funding for implementing renewable energy resources to encourage its use usually to help the country reach a sustainability goal

Being sustainable means…

We are meeting needs of the current human population without depleting resources for the future population so it would only be sustainable if the amount of energy we are supplying can be maintained indefinitely without any environmental economic or social impacts

Reasons why energy supply is not sustainable

A large proportion of how we supply energy to the general population relies on energy conversions which involve energy loss

eg when harnessing energy from coal we combust it to release heat which is then used to turn a turbine which turns a generator to convert it to electrical energy, this involves multiple energy conversions in this process leading to a huge loss of energy

usage processes arent 100% efficient such as internal combustion of petrol or diesel in a vehicle engine results in large amounts of energy loss as heat or friction or exhaust gases l, as a result only a small proportion of the energy available is used to power the vehicle

Another reason is that we rely on depletable resources much more than non depletable because we use fossil fuels to power most vehicles and for a lot of industrial processes such as electricity generation

How to become more sustainable within the energy industry

We need to invest in technology for renewable, non depletable energy resources to make them more accessible and efficient as fossil fuels will run out

Alternatives to renewables

Nuclear power is being trialled but is expensive technology to run and can have negative environmental impacts with the radioactive waste it produces

What is a fossil fuel?

A fuel made from decomposed remains of dead organisms eg coal oil or gas

Coal overview

Made from terrestrial lands plants that lived millions of years ago, when dead they partially decomposed in anoxic (no oxygen) conditions within peat to be converted into DOM, over time the peat become buried increasing temperature and pressure to form coal deposits

Properties of coal as an energy resource

Non renewable

Easy to store because it’s a solid

High energy density

Energy form is chemical as it’s stored within the chemical bonds

Depletable

High abundance (theoretical but some deposits will never be extracted because they’re too deep)

Low intermittency and predictable supply

Locational contraints: high due to extraction sites but can be used for lots of purposes

How it’s used: combusted to release heat energy eg for electricity generation or smelting in the mining industry

Conversions: conversion required to release heat but not before combustion

1- reserves will run out one day soon

2- may require more habitat damage to reach remaining deposits

3- increases usefulness as it can be stored in times of surplus and used in shortage without losing energy

4- energy not wasted/list to the environment so may reduce need to continue mining more if demand drops

5-need a small volume to release large amounts of energy

6- need to mine small volumes to release large volumes of energy, may reduce environmental impacts of mining eg noise dust

1- can be stored and release lots of energy

2- has to be combusted to release it which releases GHG snd smoke

3- we will run out one day soon need to find alternative

4- places like Antarctica may end up being mined as supply gets lower

5- increase usefulness as more available

6- loss of habitat and destruction in open cast mining

7- increases usefulness as no energy lost in conversion process

8- less energy wasted

1- increases usefulness as shouldn’t ever be a shortage until we run out of

2- high usefulness means more profit available to restore areas after mining

3- increases usefulness as can be utilised for many purposes

4- means more is used so worsens environmental impacts

5-releases large volumes of heat energy used to generate electricity or smelt metals

6- combustion releases GHG which absorb IR causing warming also releases smoke particles

how to extract a coal deposit

The location must be found first which can be done via a range of exploratory techniques including seismic surveys, IR spectroscopy as resistivity

Trial drilling can then take place to collect a physical sample of the coal deposit data can then be collected such as purity, chemical form, depth and the extent of the deposit can be recorded to determine whether mining in that location would be economically viable

If considered viable then a mining method is chosen, if the deposit is thin and close to the surface = open cast mining, if deep underground then long wall method may be required

Open cast mining vs long wall

Open cast- causes more habitat destruction, lower risk as you aren’t sending people underground,

Both involve blasting to remove overburden and unwanted material

1- baffle mounds to absorb the noise

2- water sprays to immobilise dust particles

3- planting trees, cutting off the top to increase aesthetics and stability

4- add crushed limestone to neutralise

5- sedimentation pool so suspended solids settle

Environmental impacts of the COMBUSTION of coal

Large volumes of GHG are released which absorb infrared radiation trapping it in the troposphere causing warming

Rising temps lead to land ice melt and sea level rise

Combustion also produces large volumes of smoke particles which can contain toxic chemicals and cause irritation in breathed in, can also reduce light penetration and reflect UV radiation sometimes causing an area to cool slightly if remains for a prolonged period of time

Reduced light availability reduces the rate of photosynthesis in plants

The waste product of coal combustion is ash which must be disposed of in land fill sites which have further environmental impacts such as increased rate of anaerobic decomposition causing large volumes of methane release and habitat destruction

Coal processing before and during use

First it may be broken down into smaller pieces and once combusted, flue-gas desulphurisation may occur

What is flue-gas desulphurisation

Efuennt gases produced during combustion are passed through a bed KF crushed calcium carbonate which reacts with the sulphur dioxide to remove it from the gases before they are released reducing the formation of acid rain as there is less sulphur dioxide being released into the atmosphere and mixing with water

In order for a mine to be economically viable…

There has to be enough profit to outweigh the costs that would be involved

Factors affecting the viability of a mine

The cut of ore grade of the mineral being extracted determined by the peice it can be sold for at the time and tech available to extract

Overburden depth, hardness and stability

Availability of work force to extract the material safely

Land use conflicts eg protected areas

New technologies surrounding coal usage

Coal gasification- a process performed on coal too deep to ever be extracted, it’s combusted in situ to produce a syngas mixture that contains hydrogen, carbon monoxide and methane, this can then be used to create a synthetic version of natural gas, the main benefit is that we can utilise energy stored in coal without having to extract it so energy isn’t wasted

Coal liquefaction- coal is converted into a liquid fuel using a solvent which can be used in a wider range of used eg vehicle engines yet releases large amounts of carbon dioxide

Creating smokeless coal by heating raw coal to burn off the volatiles contained, reducing evironmental impacts to an extent yet will still release large volumes of GHG

Oil and gas natural formation

Originates in sedimentary rock and the source rock which releases the oil is made from dead marine plankton which are decomposed in anoxic conditions under high temps and pressure, it then matures becoming petroleum which migrated to the reservoir rock where oil is stored (a porous and permeable rock)

Properties of oil as an energy resource

Non renewable

Fairly easy to store as it’s a liquid

High energy density

Chemical energy form

High abundance currently but it’s running out

Depletable

Low intermittency and high predictability

How it’s used- liquid fuel for vehicles

Locational constraints- high for extracting oil as we deplete existing deposits but is used and available almost everywhere eg petrol stations

Conversion needed before use- needs fractional distillation to separate the petrol but no energy conversion needed, oil combusted to release heat energy so conversion occurs during use

How to locate oil deposits

Using seismic surveys or gravimetry

How to extract oil deposits

Drill down into reservoir rock, if naturally at high pressure then oil will flow to the surface through the pipe system (primary oil recovery)

If pressure isn’t naturally high enough carbon dioxide or water is injected into the rock to increase the volume of oil (secondary oil recovery)