the energy challenge chris llewellyn smith part a – the energy challenge part b – what can/must...

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The Energy Challenge The Energy Challenge Chris Llewellyn Smith Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

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Page 1: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

The Energy ChallengeThe Energy ChallengeChris Llewellyn SmithChris Llewellyn Smith

Part A – The energy challenge

Part B – What can/must be done

Page 2: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

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

Energy FactsEnergy Facts

Page 3: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

1.6 billion people (over 25% of the world’s population) lack electricity:

Source: IEA World Energy Outlook 2006

Page 4: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

Distances travelled to collect fuel for cooking in rural Tanzania; the average load is around 20 kg

Source: IEA World Energy Outlook 2006

Page 5: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

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

Page 6: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

Annual deaths worldwide from various causes

Source: IEA World Energy Outlook 2006

* adding coal, total is 1.5 M

Page 7: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

One example of the asymmetry of the likely effects of climate change

Source: Stern Review

Page 8: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

HDI HDI ( ~ life expectancy at birth + adult literacy & school enrolment + ( ~ life expectancy at birth + adult literacy & school enrolment + GNP per person at PPP)GNP per person at PPP) and Primary Energy Demand per person, 2002 and Primary Energy Demand per person, 2002

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

Goal (?)

To reach this goal seems need

Human Development Index

tonnes of oil equivalent/capita

Page 9: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

Reaching 3 tonnes of oil equivalent (toe) per capita for everyone seems almost impossible** (completely impossible (completely impossible**

while reducing COwhile reducing CO22 emissions) emissions) – – need to lower targetneed to lower target

**at least without a large reduction in population: there could be a at least without a large reduction in population: there could be a Malthusian “solution”Malthusian “solution”

But 3 toe looks quite luxurious as a target for all – it is 77% – it is 77% of current UK per capita usageof current UK per capita usage**, which (I think) could easily be , which (I think) could easily be tolerabletolerable for Japan, Europefor Japan, Europe** 38% for USA 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

Page 10: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

Sources of EnergySources 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% - nuclear5% - hydro0.5% - geothermal, solar, wind, . . .

NB Primary energy defined here for hydro, solar and wind as equivalent primary thermal energyelectrical energy output for hydro etc is also often used, e.g. hydro ~ 2.2%

Page 11: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

Fossil FuelsFossil Fuelsareare

– 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

andand will run out sooner or later (later if we can exploit methyl hydrates)

Saudi saying “My father rode a camel. I drive a car. Saudi saying “My father rode a camel. I drive a car. My son flies a plane. His son will ride a camel”My son flies a plane. His son will ride a camel” Is this true? PerhapsIs this true? Perhaps

Page 12: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

With

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

Page 13: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

Oil SupplyOil Supply

Note: discoveries back-dated

Page 14: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

Source: ASPO

Oil SupplyOil Supply

Page 15: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

Fossil Fuel UseFossil Fuel Use

- a brief episode in the world’s history

Page 16: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

UNCONVENTIONAL OILUNCONVENTIONAL 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

Page 17: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

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

Page 18: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

Use of EnergyUse 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 31% domestic in UK(private, industrial, commercial)

Page 19: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

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%)

Source: IEA WEO. 2008 IEA Key Statistics give 2.3% of ‘Other’ (2006 data)

Page 20: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

Conclusions on Energy ChallengeConclusions 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”

Page 21: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

Meeting the Energy Challenge – Meeting the Energy Challenge – what can/must be done? Iwhat 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

Page 22: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

Coal44.5%

Oil and gas30%

Fusion

1.5%

Fission6%

Renewables18%

Energy subsidies Energy subsidies (€28 bn pa)(€28 bn pa) + R&D + R&D (€2 bn pa)(€2 bn pa)in the EU in 2001 ~ 30 Billion Euro (per year)in the EU in 2001 ~ 30 Billion Euro (per year)

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

Page 23: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

Meeting the Energy Challenge IIMeeting 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

Page 24: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

Energy EfficiencyEnergy 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

Page 25: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

The Built The Built EnvironmentEnvironment

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 (naturalventilation & lighting…)

Page 26: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

APS Study of Building EfficiencyIn 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

Page 27: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

T

TRANSPORTTRANSPORT ~ 25% of primary energy~ 25% of primary energy

• 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

Consider light vehicles• Major contributor to use of oil (passenger cars and light trucks use 63% of energy used in all transport in USA) + CO2

Report APS Study of Potential improvements.

Consider: what after the end of oil? (Biofuels, coal & gas → oil, electric, hydrogen…)

Page 28: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

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:

Page 29: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

MIT Study:

In longer term maybe Plug-in Hybrids, hydrogen (or other) fuel cells

Prospects for ImprovementsAPS 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

Page 30: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

Petrol engines much less efficient than electric motors (90%), but comparison needs overall well to wheels analysis

Page 31: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

Electric vs. Petrol

Pro electric: efficiencyOil well → 90% tank → 0.9 x 12.6% = 11% wheelsSource → 30% electricity → 0.3 x 90% = 27% battery → 0.27 x 90% = 24% wheelsSource→ ? fuel cell →≤ ? x 60% electricity → ≤?x 0.6x 90% = ? x 55% wheels

Pro petrol: weight/volumePetrol 34.6 MJ/l 47.5 MJ/kgLi ion battery (today) 0.7 MJ/l 0.5 MJ/kgH at 1 atmosphere 0.009 MJ/l 143 MJ/kgH at 10,000 psi 4.7 MJ/l 143 MJ/kgLiquid hydrogen 10.1MJ/l 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”

Page 32: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

HydrogenHydrogen Excites public and politicians - no CO2 at point of use Only helpful if no CO2 at point of productione.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 terribleNeed 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)

Page 33: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

RenewablesRenewables

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;…]

Page 34: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

Preliminary ConclusionsPreliminary 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

Page 35: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

Carbon Capture and StorageCarbon 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

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Page 37: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

After capture, compress (>70 atmos After capture, compress (>70 atmos → → liquid) transmit and store (>700m):liquid) transmit and store (>700m):

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Page 39: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

Conclusions on Carbon Capture and Conclusions on Carbon Capture and StorageStorage

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

Page 40: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

Solar PotentialSolar 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

Page 41: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

Solar (non-bio)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

Page 42: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

Projected cost of photovoltaic solar power?

$1/WpAC → 2.6 €-cents/kWhr in California (4.7 in Germany)

- requires cost ~ cost of glass!

Page 43: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

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.

Page 44: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

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)

Page 45: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

Nuclear Power 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

Page 46: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

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

Page 47: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

Uranium ResourcesUranium 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

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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]

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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 → 239Pufertile 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

Page 50: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

Thorium•Thorium is more abundant than Uranium* and 100% can be burned (generating less waste than Uranium), using 232Th + n → 233Th → 232Pa → U233

fertile fissile

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

Page 51: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

FUSIONFUSIOND + T D + T → He + N + 17.6 MeV→ He + N + 17.6 MeV

Tritium from N + Li → He + TTritium 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)

Page 52: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

FUSIONFUSION (magnetic confinement)(magnetic confinement)D + T D + T → He + N + 17.6 MeV→ He + N + 17.6 MeV

ChallengesChallenges::

1)1) Heat D-T plasma to over 100 M Heat D-T plasma to over 100 M 00CC = 10xtemperature of = 10xtemperature of

core of sun, core of sun, while keeping it from touching the wallswhile keeping it from touching the walls

This has been done using a ‘magnetic bottle’ (tokamak)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

Page 53: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

FUSIONFUSION ((magnetic confinementmagnetic confinement- cont)- 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

Page 54: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

Could what is available add up to a solution?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 withbut 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

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Page 56: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

Cost Effectiveness of Modest Cost Effectiveness of Modest COCO2 2 Saving in Saving in

IEA’s 2006 Alternative ScenarioIEA’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

Page 57: The Energy Challenge Chris Llewellyn Smith Part A – The energy challenge Part B – What can/must be done

Final ConclusionsFinal 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:particularly: CCS CCS (essential to reduce climate change) and increased efficiencyincreased efficiency, and in longer term: more solar solar and nuclear nuclear, and fusion fusion [we hope]

■ Huge R&D agenda

■ Need fiscal incentives, regulation, carbon price, more R&D, political will (globally)

The time for action is nowThe time for action is now