Nuclear Power - PowerPoint PPT Presentation

About This Presentation
Title:

Nuclear Power

Description:

Chemical reactions release a few electron-volts of energy per reaction. Nuclear Fission releases 240 Million electron volts per reaction ... – PowerPoint PPT presentation

Number of Views:104
Avg rating:3.0/5.0
Slides: 40
Provided by: martin359
Category:
Tags: nuclear | power | volts

less

Transcript and Presenter's Notes

Title: Nuclear Power


1
Nuclear Power An Energy Analysis
http//nuclearinfo.net
  • Martin Sevior
  • Associate Professor
  • School of Physics
  • University of Melbourne

2
Energy and Entropy
  • 2nd Law of Thermodynamics
  • Entropy tends to increase
  • Sharing of energy amongst all possible states
  • Life is in a very low state of entropy
  • To exist it must create large amounts of entropy
    away from itself.
  • Life requires large amounts of Energy.

3
Life and energy
  • Life takes energy from the sun

4
Energy and civilization
  • Our Civilization is based on cheap energy and
    machines
  • Previous civilizations utilized humans and
    animals. (Still the case for large parts of the
    world.)
  • Given sufficient quantities of energy our
    civilization can generate the products it needs.
    (Food, Metals, Plastics, Water)

5
Energy in Australia
  • Australias Electricity needs are currently
    supplied by 44 GigaWatts of power stations.
  • This is forecast to grow by over 2 per year to
    around 60 GigaWatts by 2020
  • On average 1.5 GigaWatts increase each year
  • Equivalent to Loy-Yang Power Station

6
Energy in the World
  • China (pop 1.4 Billion) growing at 10 per year.
  • India (pop 1 Billion) growing at 6 per year.
  • Both aspire to Western standards of living
  • China likely to achieve current Australian
    standard in 2040s
  • Effect will be to triple world energy
    consumption.
  • Only a large scale trade embargo will prevent
    them from effectively competing with the west.

7
World Energy Growth.
  • Energy Growth by source

Energy Growth by region
Projections are business as usual
Source U.S. Energy Information Administration.
8
How long can we keep using Oil?
  • The rate of Oil usage is substantially greater
    than the rate of new Oil discoveries
  • Developing Nations have become competitors for Oil

9
Global Climate Change
  • The Earths atmosphere acts as a Greenhouse.
    Traps heat that would otherwise be radiated to
    space.
  • Carbon Dioxide (CO2) is the 2nd largest
    contributor (and biggest driver)
  • Carbon Dioxide is also the fundamental byproduct
    of Fossil Fuel consumption
  • Large scale use of Fossil Fuels has substantially
    increased CO2 concentration

10
CO2 increase in the Atmosphere
11
Global Climate Change
Predicted world temperature changes
Past world temperature changes
The different curves are different predictions
based on different physical assumptions and
future CO2 emissions
The current CO2 concentration is unprecedented
over half a million years
12
Predictions for CO2 outputs
The developing world will likely produce more CO2
emissions than the West before 2020
Only a large scale trade embargo on China and
India and the rest of the developing world will
prevent competition and growth
13
The transition.
  • Having access to large amounts of cheap energy is
    vital for our civilization.
  • Over the next human generation we will need to
    manage a transition from our Fossil-Fuel based
    energy sources
  • The combination of resource depletion and Climate
    Change mitigation forces this.
  • Getting this right is vital for the world we
    leave our children.
  • I believe that this is one of the great issues
    facing my generation.

14
Nuclear Power
  • Nuclear Power has been demonstrated to work at
    large scale.
  • France (80 Nuke, 20 Hydro) and Sweden (50
    Nuke, 50 Hydro) have the lowest per capita
    greenhouse emissions of large countries in the
    OECD
  • Australia, with its reliance on Coal-powered
    electricity, has the highest

15
Nuclear Energy
  • About 6 Billion years ago a supernova exploded in
    this region of space.
  • About 1 solar mass of hydrogen was converted to
    Helium in about 1 second
  • All the elements heavier than Lithium were
    created making life possible in the solar system
  • A tiny fraction of the energy was used to create
    heavy elements like Uranium and Thorium.

16
Nuclear Energy
  • Chemical reactions release a few electron-volts
    of energy per reaction.

Nuclear Fission releases 240 Million electron
volts per reaction
A neutron is captured by 233U,235U or 239Pu. The
nucleus breaks apart and releases 2-3 more
neutrons. These in turn can induce further
fissions.
17
Nuclear energy
  • The energy release from a single fission reaction
    is about one-tenth that of an anti-matter
    annihilation.
  • There is as much energy in one gram of Uranium as
    3 tonnes of coal.
  • The reaction produces no CO2
  • So how much Uranium is present on Earth?

18
Uranium Abundance.
  • The Earths crust is estimated to contain 40
    trillion tonnes of Uranium and 3 times as much
    Thorium.
  • We have mined less than a ten millionth of this.
  • (We have extracted about half of all conventional
    Oil)
  • If burnt in a 4th Generation reactor provides 6
    Billion years of energy.
  • If burned in a current reactor enough for 24
    Million years.
  • But most is inaccessible. How much is really
    available?

19
How long could Nuclear Power last?
  • How much energy does it take to build a Nuclear
    Power plant?
  • How much energy does it take to create Uranium
    fuel?
  • How much energy does a Nuclear Power plant
    produce over its lifetime?
  • This should be greater than the energy cost.

20
The Nuclear Fuel cycle.
21
Vattenfall
  • The Swedish Energy utility operates Nuclear,
    Hydro, Wind, BioMass, Solar and Fossil Fuel
    facilities.
  • Vattenfall have performed LifeCycle Analyses for
    these.
  • These are described in Environment Product
    Descriptions EPD.
  • Useful Worlds Best Practice reference

22
Environmental Product Description
  • The overall goals of an EPD is, "through
    communication of verifiable and accurate
    information, that is not misleading, on
    environmental aspects of products and services,
    to encourage the demand for and supply of those
    products and services that cause less stress on
    the environment, thereby stimulating the
    potential for market-driven continuous
    environmental improvement".
  • Independently Audited

23
Vattenfalls EPD for Nuclear Power
  • Normalized for 1 GW Nuclear Power Plant. (NPP)
    operating for 40 years
  • Energy cost of Constructing the NPP
  • Energy cost of Mining and Milling U
  • Energy cost of enriching
  • Energy cost of dismantling the NPP
  • Energy cost of disposing the waste
  • Units PetaJoules (PJ) 1015 Joules.
  • 1 GigaWatt year 31.5 PJ

24
System Boundaries
  • In any Life Cycle Analysis there are boundaries.

25
NPP Construction
  • Typical Construction tree.

Total energy cost for Construction and
Decommissioning NPP 4 PJ
26
Mining and Milling
  • Vattenfall utilize Uranium from Olympic Dam,
    Rossing and Navoi, Uzbekistan
  • Over 40-year life of NPP total energy cost of
    mining the Uranium.
  • 5.5 PJ

27
Conversion and Enrichment
  • The Yellow Cake from the mines must be
    converted to UF6 , Neglecting U usage
  • 2 PJ
  • Then enriched to 3 235U. Vattenfall uses a
    mixture of Gaseous Diffusion and Centrifuge
  • Neglecting U used for enrichment this becomes
  • 0.5 PJ

28
Operations
  • Need to fabricate the Fuel rods
  • 1.2 PJ
  • Energy used to operate the plant and consumed in
    ongoing Maintenance
  • 1.1 PJ

29
Waste Disposal
  • Sweden has a mature multibarrier waste disposal
    plan.

Energy cost for 100,000 year isolation 4.3 PJ
30
Total Energy Cost
  • Total Energy cost over 40 years (neglecting
    additional U) 18.6 PJ
  • Energy Generated (85 efficiency) 1054 PJ
  • Energy Gain of 56
  • Repaid in 8 months of operation.

31
CO2 emissions from Nuclear
  • Vattenfall EPD calculations

32
Vattenfall CO2 emissions from other sources
33
Storm van Leeuwen and Smith
  • This website has been widely quoted
  • They find the Energy cost of building a NPP to be
    82 PJ
  • Assume Decommission cost to be 82 PJ
  • Assume Waste disposal cost to be 82 PJ
  • Predict Mining and Milling cost to be

Y Yield C U3O8
GigaJoules per Tonne
or
34
Additional Assumptions
  • No new rich deposits of Uranium will be
    discovered.
  • An extrapolation of their formula implies no net
    energy gain at Ore concentrations of 0.02 and
    below.(Rossing works at 0.03)
  • They conclude we will rapidly deplete the
    exploitable Uranium reserves with thermal reactors

35
Testing Storm and Smith
  • How well do Storm and Smith reproduce currently
    operating Uranium mines?
  • Ranger Ore 0.25
  • Predict 5.1 PJ/year, Report 0.8 PJ/year
  • Olympic Dam Ore 0.05
  • Predict 60 PJ/year, Report 5 PJ/year
  • Rossing Ore 0.035
  • Predict 69 PJ/year, Report 1 PJ/year
  • These 3 mines provide 35 of current world
    production

36
Cross Checks
  • 60 PJ is two Giga-Watt years of electricity
  • Cost of supplying this via Diesel is over 1
    Billion dollars
  • At 40 Kg U Rossing only earns 100 Million per
    year
  • Entire energy consumption of Namibia is only 50 PJ

37
Consequences
  • Even with current mining technology were far
    from exhausting our recoverable Uranium.
  • Weve mined less than 1 ten millionth of all the
    Uranium in the Earths crust.
  • Rossing provides 465 PJ of energy per year at an
    energy cost of 1 PJ
  • What can we estimate for the future?

38
Uranium Abundance
Current discovered, proven reserves amount to 3
Million tonnes, sufficient for 50 years at
present consumption rates
Rossing mine in Namibia has a Uranium abundance
of 350 ppm and provides an energy gain of 500
Extrapolating to 10 ppm provides an energy gain
of 14
4th Generation reactor (50 times more efficient
Uranium usage) provides an energy gain of 100 at
2 ppm
At least 8,000 times more Uranium can be usefully
mined using current reactors. 32,000 times more
with 4th Generation. (96 million years worth.)
39
Nuclear Power is sustainable
  • The current Uranium price is nowhere near high
    enough to sustain the energy costs predicted by
    Storm and Smith
  • There will be no lack of Uranium for thousands of
    years.
  • The motivation for 4th generation reactors is
    really to reduce the amount of waste.
Write a Comment
User Comments (0)
About PowerShow.com