Transcript The Future For Nuclear

What will it take to prevent
dangerous climate change?
An Investigation of LowCarbon Energy Sources
including Nuclear Energy
Stephen Stretton
Gonville and Caius College,
Cambridge
15th June
Contents
• Introduction: Climate change and world
energy consumption
• Potential zero carbon energy sources
• Using electricity for heating and transport
• Energy and Climate Scenarios
• UK Energy Policy
• Conclusion
*Very low CO2 emissions (less than 10% of fossil fuel equivalent)
Cover Photo: NASA
Introduction: Greenhouse Effect
•
Gases such as Carbon Dioxide (CO2)
and methane absorb re-radiated heat
in the ‘Greenhouse Effect’.
The combustion of fossil fuels such as
coal, oil and natural gas, releases CO2
into the atmosphere, increasing this
effect.
Global Concentrations of
Carbon Dioxide
400
ppmv
•
380
360
340
320
300
280
1959 1969 1979 1989 1999
Strong correlation between carbon
dioxide concentration and temperature
•
Data from Antarctic ice cores
CO2 concentration in black
Reconstructed temperature in red
Current CO2 Concentration
Pre-industrial CO2 Concentration
Effects of Climate Change
(Present Day) – Some effects already seen
Oceans damaged
Greenland ice melts (raising sea levels eventually by 7m)
Amazon rainforest collapses,
releasing carbon dioxide
Agricultural yields fall
Tropical diseases spread
World ecosystems cannot adapt
CO2
released
from
forests and
Soils
Increases in
extreme
Hundreds of millions at risk from
weather (e.g.
hunger & drought
hurricanes)
Desertification of large parts of Earth’s surface
Methane
released
from peat
bogs
Global heat
circulation
system
collapses?
Positive Feedback: Warming causes further release of greenhouse gases
Source: Adapted from Warren, R (2006)
Forest Fire: Both Causes AND
Results from Global Warming?
Forest Fire in Australia
Effects of Climate Change
• Wholesale
desertification
of Earth
possible within
100 years.
• Large
population
centres (China
and India) at
risk
• Water Wars?
Source: Lovelock, J (2006)
How Can We Save Planet Earth?
•
International Agreement on
climate is difficult
•
Climate change demands huge
cuts in emissions (Kyoto not
sufficient)
•
Politically difficulties?
•
At present the required cuts in emissions seem like an
almost impossible task – but nobody has tried!
We need a country or countries to take the lead.
•
‘Environmental Relativism’ Misses
the Bigger Picture
Energy
•
Our use of energy generates almost all
our greenhouse gas emissions
•
Energy is used in the whole economy.
•
Stop using energy and you do not have
an economy
•
But to generate that energy takes only a
small part of our efforts.
•
We can redirect these efforts
•
Investment in zero emissions generation
can be economically and strategically
beneficial.
Energy demand is rising rapidly
Energy Demand (GW)
25,000
20,000
15,000
10,000
5,000
Sustainable
Level?
1990
2000
2010
2020
2030
Year
Source: Reference Scenario, IEA World Energy Outlook (2004)
“Sustainable Level” purely illustrative (depends on assumptions on emissions intensity and climate change)
Energy consumption per person
Energy Use and CO2 Emission Per Person
Primary
Energy (kW)
per person
25
20
CO2
Emissions
(tonnes/year)
per person
15
10
5
Sustainable
Level?
Canada
Russia
Europe
Japan
US
WORLD
Brazil
China
India
Australia
Source: IEA (2003)
Sustainable Level Purely Illustrative
Energy & Climate Scenarios
•
Assume 1 Gt of CO2 increases atmospheric concentrations by
0.08ppm.
•
Assume IEA future energy demand scenarios A1T and ‘SD’.
•
Model committed temperature (the inevitable warming due to CO2
already emitted), rather than actual temperature at a certain date
(note difference with IPCC).
•
IPCC simulations do not account for positive feedback – problem
is more serious than we thought.
•
In these models we assume a climate sensitivity parameter of 4. A
doubling of pre-industrial CO2 concentrations would lead to a final
rise in temperature of 4˚C. This is close to the median of recent
estimates of this parameter.
•
Assume dangerous climate change (collapse of ecosystems,
carbon sinks become sources) begins at 2˚C.
“Business as usual” would lead to
disaster within a few decades
45,000
40,000
35,000
30,000
25,000
20,000
15,000
10,000
5,000
-
Dangerous
Threshold
Passed
Low Emissions Energy
Fossil Fuel Energy
3.50
3.00
Temperature
2.50
2.00
1.50
1.00
0.50
-
1990
2000
2010
2020
2030
2040
Committed Temperature Rise
Energy Consumption (GW)
"Fast Economic Growth" (A1) Scenario
2050
Source: IEA (2003), augmented with this author’s calculations
A expansion in low-carbon energy
can stabilise emissions…
…But still temperatures may still pass “dangerous” threshold
"Fast Economic Growth" Scenario converting to Nuclear Energy
40,000
35,000
30,000
Low Emissions Energy
Fossil Fuel Energy
Dangerous
Threshold
Passed
3.50
3.00
Temperature
2.50
25,000
2.00
20,000
1.50
15,000
1.00
10,000
0.50
5,000
-
Committed Temperature Rise
Energy Consumption (GW)
45,000
1990
2000
2010
2020
2030
2040
2050
Source: IEA (2003), augmented with this author’s scenario and calculations
A large expansion in low-emissions
capacity + less total energy used…
'Sustainable' Development (lower growth) with Nuclear Energy plus additional
reductions in consumption
Energy Consumption (GW)
Low Emissions Energy
40,000
Fossil Fuel Energy
35,000
Danger
Avoided!
3.50
3.00
Temperature
2.50
30,000
25,000
2.00
20,000
1.50
15,000
1.00
10,000
0.50
5,000
-
Committed Temperature Rise
Reduction In Use
45,000
1990
2000
2010
2020
2030
2040
2050
But can it be done??
Source: IEA (2003), augmented with this author’s scenario and calculations
Major Low-Emissions Energy Sources
Energy Source
Main Energy Vector
•
Biomass (energy crops)
Liquid Fuels or Electricity
•
Fossil fuels with CO2
Sequestration
•
Wind
•
Solar
•
Tidal
•
Wave
•
Nuclear
Electricity
Biomass: Land Area Issue?
Proportion of total world cropland
Theoretically, how much land would be needed to power the world?
800%
2000
700%
2020
600%
2050
500%
400%
300%
200%
100%
0%
Biomass*
Wind
Solar (PV)
Nuclear
• Available cropland will diminish with global
warming and population growth.
Source: Estimated from Socolow (2006) and IEA (2003)
Fossil fuels with CO2 Sequestration
•
Fossil fuels burnt
and CO2 then buried
in underground rock
formation
•
Potential solution for
areas with large
amounts of oil &
natural gas (Middle
East?)
Image Courtesy of the Energy Council of the Netherlands
Solar energy
•
Photovoltaic Cells
•
Appropriate for
equatorial regions
•
Good for those
regions without a
centralised grid
Wind
Government target: wind to generate
20% of UK electricity by 2020
= Approximately 5% of total UK energy
• Because of intermittency, for any higher
proportion, we need storage
technologies.
• However, storage technologies are only
environmentally friendly when most of
electricity is zero-carbon emitting…
(catch-22?)
Source: Defra/DTI
Nuclear
Modern Nuclear Reactors*
•
‘Passive’ safety
•
Quick construction
•
Compact
•
Constructors take price risk
•
Inexpensive decommissioning
•
Reduced fuel consumption
•
Much less waste
•
Price competitive with gas
*(e.g. Westinghouse AP1000
European PWR, Canadian ACR)
Image of AP 1000 Reactor © Westinghouse
Cost of Generating Electricity
Source: Royal Academy of Engineering (2004)
Emissions from Electricity
Generation
Major Low-Emissions Energy Sources
Energy Source
•
Biomass (energy crops)
•
Fossil fuels with CO2
Sequestration
•
Wind
•
Solar
•
Tidal
•
Wave
•
Nuclear
Main Energy Vector
(Land Area)
Liquid Fuels or Electricity
Generate
Electricity
Intermittency &
Inflexibility?
BUT electricity is only a part of total
energy use (at present)
Source: DTI
Electricity generates only one third
of CO2 emissions
Source: Defra
Can other sectors be converted to use
carbon-free electricity?
Domestic heating
(currently gas)
Transport
(currently oil)
Industry
(oil and gas)
Use (and Store?)
Carbon-Free
Electricity?
Domestic Heating
For New Homes:
•
Better house insulation
•
Heat Pumps
•
Underground air circulation
•
Air-out / Air-in heat exchanger
•
= Huge (~97%*) reduction in
Energy Use
•
•
If we use non-emitting energy, CO2 emissions
from heating would be virtually zero
Existing homes can also be converted: savings
would still be very substantial
*Estimate for Illustrative Purposes
Industry
• Industry requires a secure, reliable and
cheap energy source.
• Nuclear electricity is low cost (especially
at night) and provides a convenient
alternative to gas, hedging the price risk
of energy.
• Presently, gas prices and electricity are highly
correlated.
Transport: Short distance
• Long waiting lists for hybrid
cars e.g. Toyota Prius.
• Car companies currently
developing further models.
• Electric cars can be plugged in overnight, using
spare capacity. Battery technologies are
developing rapidly and range is increasing.
• ‘Plug-in hybrid’ are also promising. Electricity
used for short distances, advanced bio fuels(?)
for longer distances.
Transport: Long Distance
• Build a high speed rail network!
• Build new freight rail lines.
• Upgrade urban transit systems (Crossrail).
• THEN reduce prices!
• Tax Aviation more heavily (noise, CO2,
congestion)
• Encourage British tourism!
What would a zero-carbon
economy look like?
Electricity
for Road
Transport
Electricity Other
Electricity
for
Domestic
Heating
Electricity
for
Industry
Other
Sectors
Road
Freight
Aviation
(??)
Heavy
Industry /
Construction
High emissions regions already
have a nuclear industry
Source: IEA (2005)
A Solution For Britain
• Build 100-200GW of nuclear capacity over
the next 20 years.
• Aim to generate 90% of total energy
requirements in 2030 through nuclear
power.
• Use American AP 1000, European EPR or
Canadian CANDU reactor, or all three.
The French Experience
•
France in 1970s – 1990s converted 80% of electricity to Nuclear.
•
Realised economies of scale by using one design.
•
Used a single type of reactor, often with duplicate units on same
site.
•
France now has the lowest electricity prices in Europe.
•
Electricity is a major export good.
•
Britain needs a similar building program – but even more
ambitious (3x bigger).
•
We should convert all energy to nuclear (including using electricity
in heating and road transport).
Constraints on a Nuclear Expansion?
•
Uranium Reserves? - Sufficient for an expansion in the nuclear
industry. Fuel costs are only a small part of cost of nuclear – rises in
Uranium price will lead to more reserves becoming economic. Fast
breeder reactors can take over if Uranium becomes scarce.
•
Public acceptability of nuclear will increase if it is seen as a solution
to the problem of climate change.
•
Some nuclear reactors (first few) can be based at existing sites. New
reactors (e.g. AP1000) much smaller and more than one reactor can
be built in each place.
•
However, there must be a ‘bank’ developed of about 50 suitable
nuclear sites (with planning permission) across the UK (not
threatened by flooding or coastal erosion due to sea-level rises).
•
Only constraint for the UK is SKILLS. We need a massive program
to train at least 50,000 (and probably more) new nuclear engineers
over the next few years.
Summary
•
To prevent ‘dangerous’ climate change we need to act
rapidly.
•
We must invest in all low-emissions technologies.
•
Nuclear is large to generate a large part of our total
energy (not just the small part that is currently electricity).
•
Cars and domestic heating can be converted to run off
electricity. More freight can be transported by rail.
•
Cuts in consumption (e.g. aviation, long distance car
use) are also necessary.
•
“Electricity is the nervous system of civilisation”
(Lovelock).
References
Comby, B. (2006), Environmentalists for Nuclear Energy, Canadian Edition
Defra, (2006) Avoiding Dangerous Climate Change, Cambridge University Press, Cambridge
and www.defra.gov.uk
DTI (2006) 'Our Energy Challenge', Energy Review Consultation Document and www.dti.gov.uk
IAEA (2000) Annual Report
IEA (2003) ENERGY TO 2050 Scenarios for a Sustainable Future
IEA (2005) Key World Energy Statistics
Lovelock, J (2006) The Revenge of Gaia, Penguin, London
Mackay, D. (2006,Unpublished) Online notes on energy at
http://www.inference.phy.cam.ac.uk/mackay
Nuttall, W. J. (2005), Nuclear Renaissance, IOP Publishing
Royal Academy of Engineering (2004): The Cost of Generating Electricity
Socolow, R. (2006) et al.: Stabilization Wedges: An elaboration of the concept in Defra (2006)
Warren, R (2006): Impacts of Global Climate Change at different Annual Mean Global
Temperature Increases in Defra (2006)
World Energy Council (2000) Energy For Tomorrow's World
Nuclear Energy: for the
Future of Earth
Comments to:
Stephen Stretton
[email protected]
www.zerocarbonnow.org