Transcript Slide 1

The Energy Challenge
Chris Llewellyn Smith
Part A – The energy challenge
Part B – What can/must be done
Energy Facts
1) The world uses a lot of energy – at a rate of 15.7 TW
average 2.4 kW per person [UK – 5.1 kW, Spain 4.4]
- very unevenly (use per person in USA = 2.1xUK
= 48x Bangladesh)
2) World energy use is expected to grow 50% by 2030
- growth necessary to lift billions of people out of poverty
3) 80% is generated by burning fossil fuels
 climate change & debilitating pollution
- which won’t last for ever
Need more efficient use of energy (and probably a
change of life style) and major new/expanded sources
of clean energy - this will require fiscal measures and
new technology
1.6 billion people (over 25% of the
world’s population) lack electricity:
Source: IEA World
Energy Outlook 2006
Distances
travelled to
collect fuel for
cooking in rural
Tanzania; the
average load is
around 20 kg
Source: IEA World Energy Outlook
2006
Deaths per year (1000s) caused by indoor air
pollution (biomass 85% + coal 15%); total is 1.5
million – over half children under five
Source: IEA World Energy
Outlook 2006
Annual deaths worldwide from
various causes
* adding coal, total is 1.5 M
Source: IEA World Energy Outlook
2006
One example of the asymmetry of
the likely effects of climate change
Source: Stern Review
HDI ( ~ life expectancy at birth + adult literacy & school enrolment +
GNP per person at PPP) and Primary Energy Demand per person, 2002
Goal (?)
Human Development Index
To reach this
goal seems need
tonnes of oil equivalent/capita
For all developing countries to reach this point, would need
world energy use to double with today’s population, or
increase 2.6 fold with the 8.1 billion expected in 2030
If also all developed countries came down to this point the
factors would be 1.8 today, 2.4 in 2030
Reaching 3 tonnes of oil equivalent (toe) per capita for
everyone seems almost impossible* (completely impossible*
while reducing CO2 emissions)
– need to lower target
*at least without a large reduction in population: there could be a
Malthusian “solution”
 But 3 toe looks quite luxurious as a target for all – it is 77% of
current UK per capita usage*, which (I think) could easily be
tolerable for Japan, Europe
* 38% for USA
 Equity
(same energy for all) without any energy increase would
require going to 46% of current UK usage per capita at current
population level (23% for USA) - 35% with 8.1 billion
population (18% for USA)!
Equity without lots more energy (whence?) would require
changes of life style in the developed world
Sources of Energy
 World’s primary energy supply (rounded):
80 % - burning fossil fuels (43% oil, 32% coal,
25% natural gas)
10% - burning combustible renewables and
waste
5% - nuclear
5% - hydro
0.5% - geothermal, solar, wind, . . .
NB Primary energy defined here for hydro, solar and wind
as equivalent primary thermal energy
electrical energy output for hydro etc is also often used,
e.g. hydro ~ 2.2%
Fossil Fuels
are
– generating debilitating pollution
(300,000 coal pollution deaths pa in China; Didcot
Power Station [large coal & gas fired plant near Oxford]
has probably killed more people than Chernobyl)
– driving potentially catastrophic climate
change
and will run out sooner or later (later if we can exploit
methyl hydrates)
Saudi saying “My father rode a camel. I drive a car.
My son flies a plane. His son will ride a camel”
Is this true? Perhaps
W
i
t
h
With current growth, the 95 year (2100) line will be reached in:
• 2068 for oil (growth 1.2% pa but growth will  decline beyond ‘Hubbert peak’)
• 2049 for gas (growth 3.1% pa)
• 2041 for coal (growth 4.5% pa); note – some people believe coal resource much
smaller
Oil Supply
Note: discoveries back-dated
Oil Supply
Source: ASPO
Fossil Fuel Use
- a brief episode in the world’s history
UNCONVENTIONAL OIL
Unconventional oil resources* are thought to amount to ‘at
least’ 1,000 billion barrels (compared to 2,300 billion barrels
of conventional oil remaining according to the USGS)
*oil sands in Canada, extra heavy oil in Venezuela, shale oil
in the USA,…
- generates 2% of global oil supply today → 8% by 2030?
Expected increase mainly in Canada. Cost of producing
synthetic crude (which is very sensitive to price of gas or
other fuel used → steam injected to make bitumen flow) is
currently $33/barrel (vs. a few $s/barrel in Saudi Arabia)
Production of 1 barrel of crude requires 0.4 barrels of oil
equivalent to produce steam
Methyl Hydrates – Bane or Boon?
 MHs are gases (bacterially generated methane) trapped in a
matrix of water at low temperature and/or high pressure in
permafrost and marine sediments (below 500m)
 USGS (which thinks that 370 trillion m3 of natural gas are left)
estimates that there are (2,800 – 8.5M) trillion m3 of MHs
 Bane? Methane in MHs could be released by global warming;
some evidence that this happened 55.5M years ago (late
Paleocene) when the temperature rose by 5-8C
 Boon? Potentially a huge source of energy:
- Permafrost: Japanese test underway in Canada to release
by drilling into porous sandstone containing MHs (release by
pressure decrease)
- Sea: danger of ‘boiling’ sinking ships and rigs
Use of Energy
 Electricity production uses ~ 1/3 of primary
energy (more in developed world; less in developing
world)
- this fraction could (and is likely in the future to) be
higher
 End Use (rounded)
 25% industry
 25% transport
 50% built environment
(private, industrial, commercial)
 31% domestic in UK
Source: IEA WEO. 2008 IEA Key Statistics give 2.3% of ‘Other’ (2006 data)
Note that mixture of fuels used → electricity is very different in
different countries
e.g. coal ~ 35% in UK, ~76% in China (where hydro ~ 18%)
Conclusions on Energy Challenge
 Large increase in energy use expected, and needed to lift billions out
of poverty
 Seems (IEA World Energy Outlook) that it will require an increased
use of fossil fuels
– which is driving potentially catastrophic climate change*
– will run out sooner or later
There is therefore an urgent need to reduce energy use (or at
least curb growth), and seek cleaner ways of producing energy
on a large scale
IEA: “Achieving a truly sustainable energy system will call for radical
breakthroughs that alter how we produce and use energy”
*Ambitious goal for 2050 - limit CO2 to twice pre-industrial level. To
do this while meeting expected growth in power consumption would
need 50% more CO2-free power than today’s total power
US DoE “The technology to generate this amount of emission-free
power does not exist”
Meeting the Energy Challenge –
what can/must be done? I
Introduce fiscal measures and regulation to change
behaviour (reduce consumption) and stimulate R&D
(new/improved technology)
Increased investment in energy research* will be essential
*public funding down 50% globally since 1980 in real terms;
world’s publicly funded energy R&D budget ~ 0.25% of energy
market (which is $4 trillion a year)
Note – when considering balance of R&D funding, should bring
market incentives/subsidies (designed to encourage
deployment of renewables) into the picture
Energy subsidies (€28 bn pa) + R&D (€2 bn pa)
in the EU in 2001 ~ 30 Billion Euro (per year)
Renewables
18%
Fission
6%
Coal
44.5%
Fusion
1.5%
Oil and gas
30%
Source : EEA, Energy subsidies in
the European Union: A brief
overview, 2004.
Fusion and fission are displayed
separately using the IEA
government-R&D data base and
EURATOM 6th framework
programme data
Meeting the Energy Challenge II
 Recognise that the solution will be a cocktail (there is no
silver bullet), including
Actions to improve efficiency (+ avoid use)
Use of renewables where appropriate (although individually not
hugely significant globally, except in principle solar)
 BUT only four sources capable in principle of meeting a
really large fraction of the world’s energy needs:
• Burning fossil fuels* (currently 80%) – must develop & deploy
CO2 capture and storage if feasible
* remaining fossil fuels will be used
• Solar - seek breakthroughs in production and storage
• Nuclear fission - cannot avoid if we are serious about reducing
fossil fuel burning (at least until fusion available)
• Fusion - with so few options, we must develop fusion as fast as
possible, even if success is not 100% certain
Energy Efficiency
Production e.g. world average power plant efficiency ~ 30% →
45% (state of the art) would save 4% of anthropic carbon dioxide

Distribution – typically 10% of electricity lost* (→ 50% due to
‘non-technical losses’ in some countries: need better metering)

*mostly local; not in high voltage grid
 Use: - more energy efficient buildings, CHP (40% → 85-90%
use of energy) where appropriate
- smart/interactive grid
- more efficient transport
- more efficient industry
Huge scope but demand is rising faster
Note: Energy intensity (= energy/gpd) fell 1.6% pa 1990-2004
Efficiency is a key component of the solution, but cannot
meet the energy challenge on its own
The Built Environment
Consumes ~ 50% of energy
(transport 25% and industry 25%)
→ nearly 50% of UK CO2 emissions
due to constructing, maintaining,
occupying buildings
Improvements in design could
have a big impact
e.g. could cut energy used to heat
homes by up to factor of three (but
turn over of housing stock ~ 100
years)
Tools: better information,
regulation, financial instruments
Source: Foster and Partners. Swiss Re
Tower uses 50% less energy than a
conventional office building (natural
ventilation & lighting…)
APS Study of Building Efficiency
In USA: buildings use 40% of primary energy • Heating and cooling: 500 GW primary energy (65% residential; 35%
commercial)
• Lighting: 250 GW primary energy (43% residential; 57% commercial)
22% of all US electricity (29% world-wide)
[Spain: total electricity 31 GW ~ 90 GW primary energy, thermal equivalent]
Measures on lighting:
Better use of natural light; reduce ‘over-lighting’; more efficient bulbs:
Traditional incandescent bulbs ~ 5% efficient
Compact fluorescent lights ~ 20% efficient
Detailed study: in USA, upgrading residential incandescent bulbs
and ballasts and lamps in commercial buildings could save = 3% of all
electricity use ( If this finding translates pro rata to UK, it would save
one 1 GW power station!)
In longer term: LEDs (up to 50% efficient); R&D needed → white light
+ reduce cost
TRANSPORT ~ 25% of primary energy
Consider light vehicles
T
• Major contributor to use of oil (passenger cars and light
trucks use 63% of energy used in all transport in USA) + CO2
• Growing rapidly e.g. IEA thinks 700 million light vehicles today →
1,400 million in 2030 (China: 9m → 100m; India: 6.5 m → 56m)
Is this possible?
Can certainly not reach US levels: for the world’s per capita petrol
consumption to equal that in the USA, total petrol consumption would
have to increase by almost a factor of ten
Report APS Study of Potential improvements.
Consider: what after the end of oil? (Biofuels, coal & gas
→ oil, electric, hydrogen…)
Trends:
Improvements: front wheel
drive, engine, transmission,
computer control…..
1975 – 1985 mandatory Corporate
Average Fuel Economy standards
improved annually, but thereafter
manufactures continued to improve
efficiency but built heavier, more
powerful cars:
Prospects for Improvements
APS Considers 50 mpg (US) by 2030 reasonable* (decreased weight:
-10% → 6-7% fuel economy), improved efficiency, hybrids + possibly
Homogeneous Charge Compression Ignition, variable compression
ratios, 2/4 stroke switching….
*4.7 litres/100km
MIT Study:
In longer term
maybe Plug-in
Hybrids, hydrogen
(or other) fuel cells
Petrol engines much less efficient than electric
motors (90%), but comparison needs overall well to
wheels analysis
Electric vs. Petrol
Pro electric: efficiency
Oil well → 90% tank → 0.9 x 12.6% = 11% wheels
Source → 30% electricity → 0.3 x 90% = 27% battery → 0.27 x 90% = 24% wheels
Source→ ? fuel cell →≤ ? x 60% electricity → ≤?x 0.6x 90% = ? x 55% wheels
Pro petrol: weight/volume
Petrol
Li ion battery (today)
H at 1 atmosphere
H at 10,000 psi
Liquid hydrogen
34.6 MJ/l
0.7 MJ/l
0.009 MJ/l
4.7 MJ/l
10.1MJ/l
47.5 MJ/kg
0.5 MJ/kg
143 MJ/kg
143 MJ/kg
143 MJ/kg
APS “Hydrogen fuel cell vehicles unlikely to be more than a niche
product without breakthroughs…challenges are durability and cost of
fuel cells, including catalysts, cost-effective on-board storage, hydrogen
production and deployment and refuelling infrastructure”
Hydrogen

Excites public and politicians
- no CO2 at point of use

Only helpful if no CO2 at point of production
e.g. - capture and store carbon at point of production
- produce from renewables (reduced problem of
intermittency)
- produce from fission or fusion (electrolysis, or ‘catalytic
cracking’ of water at high temperature)

Usually considered for powering cars:
Excellent energy/mass ratio but energy/volume terrible
Need to compress or liquefy (uses ~ 30% of energy, and adds to
weight), or absorb in light metals (big chemical challenge – being
addressed by Oxford led consortium)
Renewables
Could they replace a significant fraction of the 13 TW (and
growing) currently provided by burning fossil fuels?
 Solar could in principle power the world – given breakthroughs in energy storage
and costs (which should be sought) – see later
 Hydro - already significant: could add up to 1TW thermal equivalent
 Wind - up to 3 TW thermal equivalent conceivable
 Burning biomass - already significant: additional 1 TW conceivable
 Geothermal, tidal and wave energy - 200 GW conceivable
All should be fully exploited where sensible, but excluding
solar, cannot imaging more than 6 TW – huge gap as fossil
fuels decline
[Conclusions are very location dependent: geothermal is a major player in
Iceland, Kenya,…; the UK has 40% of Europe’s wind potential and is well
placed for tidal and waves; the US south west is much better than the UK for
solar; there is big hydro potential in the Congo;…]
Preliminary Conclusions

Must improve efficiency – but at best will only stop growth
(unless we are prepared to tolerate a very inequitable world). Needs
initial investment, but can save a lot of money
 Must exploit renewables to the maximum extent reasonably
possible (not easy as it will put up costs)
 Likely most of remaining fossil fuels will be burned. If so,
carbon capture and storage is the only way to limit climate
change (but will put up costs)
 In the long-run, will need (a combination of):
- Large scale solar
- Much more nuclear fission
- Fusion
Carbon Capture and Storage
 In principle could capture CO2 from power stations (35%
of total) and from some industrial plants (not from cars,
domestic…)
 Capture and storage - would add ~ $2c/kWh to cost for gas;
more for coal - in both cases much more initially
 Storage - could (when location appropriate) be in depleted
gas fields, depleted oil fields, deep saline aquifers
 Issues are safety and cost (capture typically reduces efficiency
by 10 percentage points, e.g. 46% → 37%, 41% → 32%,..)
With current technology: capture, transmission and storage
would ~ double generation cost for coal
After capture, compress (>70 atmos →
liquid) transmit and store (>700m):
Conclusions on Carbon Capture and
Storage
 Mandatory if feasible and the world is serious about climate
change - big potential if saline aquifers OK (said to be plenty in China
and India)
 Large scale demonstration very important
- First end-to-end CCS power station just opened in N Germany
(30MW oxy-fuel add–on → steam to turbines in existing 1 GW power
station)
- EU Zero Emissions Power strategy proposes 12 demonstration plants
(want many, in different conditions) by 2015: needed to develop/choose
technologies, and drive down cost, if there is going to be significant
deployment by 2030
-Meanwhile should make all plants ‘capture ready (post-combustion or
oxy-fuel)
 It will require a floor for the price of carbon
Solar Potential

Average flux reaching earth’s surface is 170 Wm-2, 220 Wm-2 at
equator, 110 Wm-2 at 50 degrees north
170 Wm-2 on 0.5% of the world’s land surface (100% occupied!)
would with 15% efficiency provide 19 TW


Photovoltaics are readily available with 15% efficiency or more,
and concentrated solar power can be significantly more efficient
Photosynthesis:

Natural: energy yields are vary from 30-80 GJ/hectare/year (wood) to 400-
500 GJ/hectare/year (sugar cane)
100 GJ/hectare/year corresponds to 0.3 Wm-2, or 0.2% of average solar flux at
earth’s surface, so even sugar cane is only 1% efficient at producing energy.
At 0.3 Wm-2, would need 15% of world’s land surface to give 10 TW

Artificial: exciting possibility of mimicking photosynthesis in an artificial
catalytic system to produce hydrogen (to power fuel cells), with efficiency of
possibly 10% (and no: wasted water, fertiliser, harvesting) – should be
developed
Solar (non-bio)
 Photovoltaics (hydrogen storage?)
 Concentration (parabolic troughs,
heliostats, towers)
High T:
→ turbines (storage: molten salts,
dissociation/synthesis of ammonia,
phase transitions in novel materials…)
→ ‘thermal cracking’ of water to
hydrogen
Challenges: new materials, fatigue…
 Thermal (low T): hot water (even in UK not stupid), cooling
Projected cost of photovoltaic solar power?
$1/WpAC → 2.6 €-cents/kWhr in California
(4.7 in Germany)
- requires cost ~ cost of glass!
Solar Parabolic Trough
Mirrors + receivers + conventional (super) heated steam
turbine. Generally solar/fossil hybrids (can be ISCC).
Considerable experience (a few with heat storage).
Individual systems < 80 MW.
Heliostats
Heats molten salt to 565C (buffer)
→ steam, or air or water. May
(initially at least) be hybrid
(including ISCC). Pilots built, but
none yet on commercial scale: 50
– 200 MW.
Dish/Stirling
engine
Up to 750C, 20 MPa. High
efficiency (30% achieved.
Small (< 25 kW each). Modular.
May be hybrid. Needs mass
production to drive down cost
(can → Brayton turbine)
Nuclear Power
 Recent performance impressive – construction ~ (?) on
time and (?) budget, excellent safety record, cost looks OK
New generation of reactors (AP1000, EPR) – fewer
components, passive safety, less waste, lower down time
and lower costs
 Constraints on expansion
- snail’s pace of planning permission (in UK +…)
- concerns about safety
- concerns about waste
- proliferation risk
- availability of cheap uranium

Problems and limitations
• Safety – biggest problem is perception (arguable that
Didcot power station has killed more people than
Chernobyl)
• Waste – problem is volume for long term disposal
US figures:
Existing fleet will → 100,000 tonnes (c/f legislated
capacity of Yucca mountain = 70,000 tonnes)
If fleet expanded by 1.8% p.a. → 1,400,000 tonnes at
end of century
• Proliferation – need to limited availability of enrichment
technology, and burn or contaminate fissile products
Uranium Resources
. US DoE Data/Projections:
Assuming 1.8%
p.a. growth of
world’s nuclear
use
Unless there is
much more than
thought, or we
can use
unconventional
uranium, not
long to start
FBRs
Will need to use thorium and/or fast breeders in ~ 50 years
Need to develop now
Different Fuel Cycles
• Goals
- reduce waste needing long-term disposal (destroy: [99.5+%?] of
transuranics, and heat producing fission products [caesium,
strontium])
- burn or ‘contaminate’ weapons-usable material
- get more energy/(kg of uranium)
• Options (some gains possible from improved burn-up in once
through reactors; as in all thermal power plants, higher temperature
→ more energy/kg of fuel)
• Recycle in conventional reactors – can get ~2 times energy/kg +
reduce waste volume by factor 2 or 3 (note: increase proliferation
risk + short-term risk from waste streams)
• Fast breeders
[Mixed economy: conventional reactors + burn waste by having
some FBRs or accelerator based waste burners]
Plutonium Fast Breeders
• In natural uranium, only 235U (0.7%) is fissile, but can
make fissile Plutonium from the other 99.3%
238U
+ n → 239Np → 239Pu
fertile
fissile
 order 60 times more energy/kg of U
 more expensive (and not quite so safe + large plutonium
inventory), but far less waste → storage
Potential problem
slow ramp up* (1 reactor→ 2 takes ~ 10 years)
* Based on figures from Paul Howarth:
1 GWe FBR needs stockpile of ~ 30 tonnes Pu to operate ~ 12 years
[30 tonnes of Pu is output of a 1 GWe LWR for ~ 140 years]
After 12 years → 30t Pu to refuel + 30t Pu to start another
Thorium
•Thorium is more abundant than Uranium* and 100% can be
burned (generating less waste than Uranium), using
+ n → 233Th → 232Pa → U233
fertile
fissile
232Th
Thermal neutrons OK, but then to avoid poisoning need continuous
reprocessing → molten salts
* accessible 232Th resource seems (??) to be over 4 Mt, vs. 0.1 Mt for
235U
(if total accessible U resource is 16 Mt)
• Need Pu or highly enriched U core (→ large number of
neutrons) or neutrons from accelerator driven spallation source*
in order to get started
Relatively rapid ramp up but long doubling time (?)
* avoids having a near critical system, but economics suggest
AD system’s best potential is for actinide burning
FUSION
D + T → He + N + 17.6 MeV
 Tritium from N + Li → He + T
So the raw fuels are lithium (→ T), which is very abundant, and water (→ D)
 The lithium in one laptop battery + half a bath of water would
produce 200,000 kW-hours of electricity
= EU per-capita electricity production for 30 years
without any CO2
This ( + fact that costs do not look unreasonable: might be able
to compete with fast breeders?) is sufficient reason to develop
fusion as a matter of urgency
 Now focus on magnetic confinement (inertial fusion should also
be pursued, but is a generation behind, and faces additional
challenges)
FUSION (magnetic confinement)
D + T → He + N + 17.6 MeV
Challenges:
1) Heat D-T plasma to over 100 M 0C = 10xtemperature of
core of sun, while keeping it from touching the walls
This has been done using a ‘magnetic bottle’ (tokamak)
The Joint European Torus (JET) at Culham in the UK has
produced 16 MW of fusion power
2) Make a robust container (able to withstand huge neutron
bombardment ~ 2MW/m2)
3) Ensure reliability of very complex systems
FUSION (magnetic confinement- cont)
Attractions: unlimited fuel, no CO2 or air pollution, intrinsic safety,
no radioactive ash or long-lived nuclear waste, cost will be
reasonable if we can get it to work reliably
Disadvantages: not yet available, walls gets activated (but half
lives ~ 10 years; could recycle after 100 years)
Next Steps:
 Construct a power station sized device (→ at least 10 times
more energy than input) – this has just been agreed: it is called
ITER and is being built by EU, Japan, Russia, USA, China, S
Korea, India in Provence
 Build a Fusion Materials Irradiation Facility (IFMIF) and
develop fusion technologies
IF these steps are taken in parallel, then - given adequate
funding, and no major adverse surprises - a prototype fusion
power station could be putting power into the grid within 30
years
Could what is available add up to a solution?
 Known technologies could in principle meet needs with
constrained CO2 until the middle of the century, but only with
- technology development, e.g. for carbon capture and storage:
essential
- measures to increase efficiency (cost is a big driver, but need
strong regulation also)
- all known low carbon sources pushed to the limit
 After fossil fuels depleted, must continue to use everything
available. But the only major potential contributors are
- Solar which must be developed
- Nuclear fission → fast breeders
- Fusion: which must be developed
Cost Effectiveness of Modest CO2 Saving in
IEA’s 2006 Alternative Scenario
(‘only’ +30% CO2 in 2030: +50% in Reference Scenario)
 Supply side investment saved: $3.0 trillion* to 2030
*out of over $29 trillion in reference scenario, which won’t necessarily be
available
 Additional demand side investment*: $2.4 trillion to 2030
*by consumers, who cumulatively save $8.1 trillion in power bills – so
investment very cost effective (even with an enormous discount rate as pay
back times ~ 3 years in OECD/1.5 years developing countries)
Gains biggest in developing world
‘low hanging fruit’; demand side work cheaper
but implementation requires many individual investment decisions,
by people
- such as landlords, developers who won’t be paying the power bills
- in the developing world, without access to capital
- in developed world, without a great interest in individually small savings
Final Conclusions
■ Huge increase in energy use expected; large increase needed
to lift world out of poverty
■ Challenge of meeting demand in an environmentally
responsible manner is enormous. No silver bullet - need a
portfolio approach
■ Need all sensible measures: more wind, hydro, biofuels,
marine, and particularly: CCS (essential to reduce climate
change) and increased efficiency, and in longer term: more
solar and nuclear, and fusion [we hope]
■ Huge R&D agenda
■ Need fiscal incentives, regulation, carbon price, more R&D,
political will (globally)
The time for action is now