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 wont 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 worlds 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 todays 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)
Malthusian solution
But 3 toe looks quite luxurious as a target for all it is 77% of

need to lower target

*at least without a large reduction in population: there could be a

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
Worlds 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 worlds 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 todays 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; worlds 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% Fusion 1.5%

Coal 44.5%

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 worlds 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 worlds 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 breakthroughschallenges 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 Europes 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 addon 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 earths 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 worlds 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 earths surface, so even sugar cane is only 1% efficient at producing energy. At 0.3 Wm-2, would need 15% of worlds 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 - snails 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 worlds 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
fissile

fertile

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
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 systems 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 IEAs 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 wont 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 wont 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