PHYS1211—part 1; energy intro,energy sources, nuclear energy

• The syllabus is based on the textbook: “Energy—Its Use and theEnvironment”, with some additional information provided in theseslides

• Lecturer for the first half of the course: Prof. Michael Ashley, Room137, Old Main Building, m.ashley@unsw.edu.au, ph 9385-5465

• Dr. Oleh Klochan will be taking the last lecture in week 1, and allthree lectures in week 2.

• These notes are available here:http://mcba11.phys.unsw.edu.au/˜mcba/PHYS1211/ including aversion with a white background to reduce the use of printer ink.

• A link to the Moodle website for the course is herehttp://moodle.telt.unsw.edu.au/course/view.php?id=27860

• NOTE: these notes will be changed (slightly) as the course goes on,so don’t print them all out immediately!

Important points• The laboratory handbook is available for collection from the First

Year Lab, Level 1 Old Main Building.• Read the course outline and Moodle site carefully, particularly with

respect to the project and assessment.• You will be giving a group presentation in the lab in one of weeks 5,

6, or 7.• You will be handing in a group project report during the lab in week 7.• Groups are normally three people in size.

Energy: introduction• A brief introduction to the concept of “energy”• Energy and society• Energy in the news—the big energy issues we are facing today:

I Climate change: is our energy usage wrecking our planet?I Peak oil and oil prices: are we running out of one of the world’s key

energy resources?I The food crisis: the struggle to provide the food energy for a growing

world population.

• Energy and Australia: our place in the world, and how we are affectedby coming changes.

Energy• Energy is one of the most fundamental concepts in science

I This is true not only for physics, but also in...I Chemistry: energy considerations determine which chemical reactions

occur, and how fast they go.I Biology: energy is fundamental for life; all living organisms have ways

of extracting energy from their environment for their own use.I Computation: there are fundamental limits to the minimum amount

of energy required to process information.

Types of energy• Mechanical Energy

I Kinetic (movement) and Potential (e.g., a compressed spring, or anobject in a gravitational field) Energy.

• Thermal EnergyI Energy associated with heat.

• Chemical EnergyI Energy stored in the chemical structure of a substance.

• Electromagnetic EnergyI Energy in electric fields, or electromagnetic radiation (i.e., light).

• Nuclear EnergyI Energy contained in the atomic nucleus.

Law of Conservation of Energy• Energy cannot be created or destroyed—it can only be converted

from one form to another, e.g.,I A pendulum converts between kinetic and potential energy as it

swingsI An aircraft can convert between kinetic energy (proportional to the

airspeed squared) and potential energy (proportional to altitude).I.e., you can dive to increase your speed. Note that there appear tobe “losses” in the conversion; the energy isn’t actually lost, butconverted into other forms such as heat.

I Burning hydrocarbons (e.g., fossil fuels) produces thermal energy byextracting chemical energy. The resultant molecules (e.g., CO2 andwater) are more stable that the original hydrocarbons; you have toput energy in to reverse the process.

Relevance of energy to aviation• An understanding of aircraft performance is aided by understanding

energy conservation (e.g., flows between kinetic and potentialenergy).

• The aircraft engine is a device to convert chemical energy into kineticenergy.

• Energy efficiency, through clever engineering, reduces operating costs.• With fossil fuel usage needing to be phased out, alternative fuels

must be considered, e.g.,I biofuels,I electricity, https://www.youtube.com/watch?v=0jyksb61FNw

https://www.youtube.com/watch?v=ohig71bwRUEhttps://lilium.com/technology/

I alternative aircraft designs, e.g., zeppelins.

Annual global energyNOTE: energy is measured in Joules (more about this in the next lecture).

• Total annual energy requirement in food for the world population:I 2.7 × 1019 J

• Total world energy production (coal, oil, nuclear, hydro etc.).I 4.8 × 1020 J

• Total energy received from the Sun at the Earth’s surface.I 2.7 × 1024 JI This is about 6000 times our current energy needs.

Energy in society• “Energy” is not just a concept used by scientists, e.g.,

I Energy plays a major part in the national and global economy.I Energy issues (such as climate change) are increasingly becoming

central in politics.I These issues affect our everyday lives—e.g., high petrol prices, effects

of climate change such as sea-level rise, drought, bushfires.

Energy and politics• Climate change and energy supply have been major political issues

recently, although less so than their seriousness deserves.I Climate change and in particular the “carbon tax”, coal mining, and

“fracking”, have been important political issues in Australia recently.I Climate chance has been a significant factor in recent federal

elections.I Disagreements on climate change policy have been factors in

leadership changes in both main political parties.

Energy and the economy• Australia’s exports energy to the value of $40 billion per year (mostly

coal).I Energy imports are about $20 billion per year (mostly oil) .I The Gillard-era “carbon tax” raised $4.2 billion per year.I Six of the top 10 “Fortune 500” largest companies are energy

companies.

Energy issues in the news• Climate change

I Caused by our use of fossil fuels for energy, producing greenhousegases (particularly carbon dioxide, CO2).

I The “carbon tax” introduced by the Australian Government.• Recent energy-related disasters:

I Lac-Magantic crude-oil train explosion (Canada, 2013; 6 massiveexplosions killing 47 people).

I Power blackout (India, 2012; 670 million people, no power for 2days).

I Fukushima nuclear plant (Japan, 2011; tsunami causes three coremeltdowns; $300 billion in costs).

I BP Deepwater Horizon oil rig disaster (US, 2010; largest oil spill inUS history; $80 billion in costs).

I Pikes River coal mine explosion (New Zealand, 2010; 29 deaths).• Food crisis

I Food prices spiked in 2007–2008 (global food crisis).

The greenhouse effect• The greenhouse effect warms the Earth by about 33 degrees celcius.• Without it the planet would be permanently frozen and uninhabitable.• Recent human-caused changes in greenhouse gas concentrations are

changing the balance and causing increasing global temperatures.• The Keeling Curve measures the CO2 concentration in the

atmosphere. Measurements were begun at Maula Loa Observatory(Hawaii) in 1958. Tasmania’s Cape Grim is one of the best sites inthe world to make the measurement.

• In February 2016, the Cape Grim average CO2 levels exceeded 400ppm (parts per million) for the first time, up from about 260 ppmpre-industrial. Without active, artificial, withdrawl of CO2 from theatmosphere, CO2 will not go below 400 ppm again for thousands ofyears.

Melting arctic icehttps://www.climaterealityproject.org/blog/watch-arctic-oldest-sea-ice-disappear-over-last-25-years

Albedo effect• Ice reflects sunlight and helps keep the Earth cool.• Open ocean or land surfaces are much less reflective and absorb more

solar energy.• Melting ice means more future climate change.

I The CO2 has a direct effect on climate.I But also a delayed effect due to melting ice.

Climate change: likely effects onAustralia

• End to agriculture in the Murray-Darling Basin.• Destruction of the Great Barrier Reef.• Up to 9500 heatwave deaths per year.• GDP collapse of 4.8%; a 7.8% fall in real wages.• 5.5 million exposed to dengue virus.• Political instability within neighbouring countries.

(According to the Garnaut Report, 2008).

Energy and Australia• Australians use energy equivalent to about 6 tonnes of oil per person

annually. Compare this with...I America and Canada: about 8 toe/person/year.

I Europe and Japan: about 4 toe/person/year.

I China: about 1.3 toe/person/year.

• Australia is a major exporter of energyI 4th worldwide after Russia, Saudi Arabia and Norway.

I World’s largest exporter of coal.

Energy and Australia• Australia has the fourth largest reserves of coal worldwide.

I Enough to last about 200 years at current production rates.I But relatively lille oil and gas.

• Australia is a major producer and has large reserves of uranium.

Energy and Australia• Unfortunately, coal—the energy source we have in abundance—is the

dirtiest fuel in terms of its carbon pollution.I Will we clean up our act by phasing out the use of coal?

I This could have significant impact on our economy.

• Can we work out how to use coal cleanly by means of carbon captureand storage?

I The technology is still in an early stage and unproven.• Can we argue that Australia is a special case because of its coal

dependence and too small to affect the global picture?I This is what we argued in Kyoto—however, it substantially weakens

the case for a global agreement on emissions reduction.

• Should we be using our uranium reserves and adopting nuclear poweron a significant scale?