Energy carriers

Energy carriers

Energy carriers in our daily lives

Biomass (food, fuel, fertilizer)

Fossil fuels: oil (liquid), coal (solid), natural gas

Heat (solar, geothermal)

Electricity: through electric grid

Electricity: through battery or fuel cell (chemical energy)

Uses for specific carriers

What can you use for heat? Solar radiation, geothermal, burn biomass or any fossil fuel, dissipate electricity in a resistance => EVERYTHING

What can you use for transportation?Yourself (biomass), animals (biomass), oil (cars,buses, trains, planes), compressed or liquid natural gas (cars, buses, trains), coal (trains), electricity (grid transportation: bus, tram, train), electric unit (battery or fuel cell) => almost everything.

Then why is oil the best transportation fuel ever?

What can you use for light? Electricity, oil, gas, biomass

What can you use for appliances? ELECTRICITY

Important properties of energy carriers

1) Abundance

2) Availability

3) Cost (economic)

4) Rate of supply (renewable vs. fossil)

5) Energy density (MJ/kg)

6) Time-dependence of supply

7) Storage

8) Distribution

9) Production: centralized or distributed

10) Environmental impacts (local: pollution / global: climate)

Why does energy matter?

Not everyone has enough energy (ACCESS)

Some energy supplies are uncertain (SECURITY)

Some energy sources are in finite global supply (SCARCITY)

Energy sources are not equally geographically distributed (DISTRIBUTION)

Some energy sources are intermittent (STORAGE)

Local environmental impacts from energy use (POLLUTION)

Environmental impacts from energy use are changing the earth's climate (GLOBAL CATASTROPHE)

Energy densities

What do you estimate the density of different energy carriers to be?

For food: need ~ 2500 kcal/day

1000 kcal ~ 4 MJ

so ~ 10 MJ per day.

How many kg of rice or pasta (carbohydrates) or cookies (carbohydrates + fat) do you need to eat per day?

0.75 kg or rice or pasta: 15 MJ/kg or 360 kcal/100g

0.5 kg of cookies: 20 MJ/kg or 500 kcal/100g

Energy densities of selected carriers

Food dry weight: fat = 39.2 MJ/kgprotein = carbohydrates = 17.2 MJ/kg

(reason why food labels are in weight, not calories)

Biomass: 10 MJ/kg (green wood) => 20 MJ/kg (sugar cane bagasse, cotton hulls, oven-dried wood)

Coal: 17 MJ/kg (lignite) => 31.4 MJ/kg (anthracite)

Oil: 42 MJ/kg (crude) => 46 MJ/kg (kerosene)

Methane: 55.5 MJ/kg

Hydrogen: 142 MJ/kg

Uranium in light water reactor: 443'000 - 3'456'000 (enriched 3.5%) MJ/kg

foodbiomass

foodbiomass

Sources: USA Energy Information Agency Annual Energy Review 2005 , USA Census Measuring America (2002)

USA per capita energy consumption 1795-2006(does not include biomass for food)

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50

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40017

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1809

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1837

1851

1865

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1991

2005

Year

Ener

gy in

GJ

per c

apita

Coal

Natural gas

Petroleum

Nuclear

Hydroelectric

Geothermal

Solar PV

Wind

Wood

Total

2000 Watt society

USA per capita energy consumption 1795-2006

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40017

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Total fossil

Nuclear

Total renewable

Total


USA total energy consumption 1795-2006

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20

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10017

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1809

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Exa

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in 1

00%

Total fossil

Nuclear

Total renewable

Total

Population (100% = 2006)


Austria Domestic Energy Consumption 1830-1995

Source: Krausmann 2002

Includes food biomass

Comparison of per capita DEC in the UK and Austria 1830-2000

Source: Krausmann 2007

Includes food biomass

Fossil Abundance

Proved reserves (BP 2008)

0

5,000

10,000

15,000

20,000

1981 1986 1991 1996 2001 2006

Exaj

oule

s

Oil: Proved reserves

Natural gas: Proved reserves

Coal: Proved reserves

Abundance, but for how long?

Calculate R/P = Reserves / Production

Result is years left if nothing changes (no new discoveries, no change in production rates)

In 1980, R/P for oil 30 years, gas 60 years

In 2007, R/P for oil 40 years, gas 60 years (???)

For coal: 2007 R/P is 145 years, down from 180 in 2004

Total fossil R/P in 2007 is 80 years, down from 90 in 2004

OIL

Abundance, access, distribution: OIL

Source: BP Statistical Review of World Energy 2008

Peak Oil?

Prediction of Marion King Hubbert, 1956

Hubbert's peak

Zittel, Schindler et al 2004:(non-OPEC countries)

Proven reserves: no peak oil.


Reasons for increase: extraction/prospection improvements?inflation of reported reserves for OPEC quotas ?or to avert economic loss of confidence?

World crude oil prices, 1968-2006

0102030405060708090

Pri

ce o

f one

bar

rel i

n U

SD EIA Nominal

EIA "Real" 2000

Using 2000 CPI

Using 2006 CPI

Source: EIA 2007 http://www.eia.doe.gov/emeu/international/oilprice.htmlCPI from http://oregonstate.edu/cla/polisci/faculty/sahr/sahr.htmOwn calculation

Crude oil prices, constant $

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40

60

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120

1860 1880 1900 1920 1940 1960 1980 2000

2007

$ p

er b

arre

l

Any reasons for fluctuations?

Sou

rce

http

://w

ww

.wtr

g.co

m/p

rices

.htm

More recent prices: light crude futures

Sou

rce:

200

8 ht

tp:/

/fut

ures

.tra

ding

char

ts.c

om/

This week

World-wide oil trade


Transportation of oil: ship, pipeline, truck

Kazakhstan, source USA Energy Information Agency 2004-2005

Eurasia and pipelines

Source USA EIA 2004-2005

Pipelines, continued

Source USA CIA 2003 (via EIA)

Geopolitics and pipelines: blue stream

Source: Radio Free Europe Free Liberty

Coal

“Down the mine” by Orwell (1937)

“ Our civilization, pace Chesterton, is founded on coal, more completely than one realizes until one stops to think about it. The machines that keep us alive, and the machines that make machines, are all directly or indirectly dependent upon coal. In the metabolism of the Western world the coal-miner is second in importance only to the man who ploughs the soil. He is a sort of caryatid upon whose shoulders nearly everything that is not grimy is supported. For this reason the actual process by which coal is extracted is well worth watching, if you get the chance and are willing to take the trouble. “

“ There are still living a few very old women who in their youth have worked underground, with the harness round their waists, and a chain that passed between their legs, crawling on all fours and dragging tubs of coal. They used to go on doing this even when they were pregnant. And even now, if coal could not be produced without pregnant women dragging it to and fro, I fancy we should let them do it rather than deprive ourselves of coal. “

Integral text online: http://www.george-orwell.org/Down_The_Mine/0.html

King Coal


Lots of coal left: what does it mean?

Coal is currently mainly used for electricity generation (thermal power plants).

When oil runs out or becomes too expensive, coal can be transformed into a high energy density liquid through the process of "coal liquefaction" (already done by the Nazis and Apartheid South Africa).

Break-even costs for coal liquefaction? estimated at 30-60 $/barrel (currently above 60 $/barrel since mid-2005).

Prediction difficulties

Source: Nebojsa Nakicenovic, UNU, 1997

Evolution of CO2/energy?

CO2 emissions per unit primary commercial energy

15.8

16.0

16.2

16.4

16.6

16.8

17.0

17.2

17.4

17.6

1970 1975 1980 1985 1990 1995 2000 2005

Ton

s C

arbo

n / T

eraj

oule

Cumulative CO2 emissions

Cumulative CO2 fossil emissions since 1965

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1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010

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on

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Electricity and electricity mixes

Uses: electricity

Important properties of energy carriers

1) Abundance

2) Availability

3) Rate of supply (renewable vs. fossil)

4) Energy density (MJ/kg)

5) Time-dependence of supply

6) Storage

7) Distribution

8) Production: centralized or distributed

9) Environmental impacts (risk, pollution)

Electricity: a final energy from many primary sources

Hydraulic (via solar and atmospheric processes and water pressure turning mechanical turbines)

Nuclear (via supernova nucleosynthesis and galactic processes, extraction, refining, controlled fission heating water and turning mechanical turbines)

Wind (via via solar and atmospheric processes and air pressure turning mechanical turbines)

Photovoltaic Solar (solar radiation via the photoelectric effect in high-tech Si chips)

Fossil (Solar radiation, geothermal processes, time, extraction, refining, burning to heat water and turn mechanical turbines)

Energy carrier properties for electricity

Energy carrier Storage Distribution Environmental impacts

Electricity Requires electric grid Can be both

Gasoline Possible VERY LOCAL

Natural Gas VERY LOCAL

Coal Possible LOCAL

Nuclear Pollution risks Pollution risks LOCAL

Solar Decentralized

Wind Not possible Decentralized

Production: centralized or

distributedNot possible

(except in repumping

dams)

Depends on production mechanism, usually fossil

Requires tanker ships, pipelines

Air pollution, water pollution, climate change

Possible but difficult

Possible but difficult (pipelines, LNG infrastructure)

Air pollution, water pollution, climate change (but cleaner than

oil)Ship, train, truck (no passive transport like

pipelines over long distances)

Air pollution, water pollution, climate change (much worse than

oil)

Waste disposal is unsolved problem. Uranium itself may be as

toxic as lead.Not possible

(except in plants)

Worldwide, more or less

Depends on technology choice, trade-offs in land-use choices.

Sea coast, mountain ridges

Landscape, usually considered not very high

Hydro good storage large river systems LOCAL Ecosystem disruption, methane

CO2 emissions from electricity

Electricity Source

Units

Fossil power plants

3.44 0.03 0.275

3.84 0.01 0.338

Oil 3.45 0.01 0.238Natural Gas 3.1 0.01 0.167

Nuclear power plants 3.52 0.01 0.002

RenewableWind 0.05 4 0.003

Solar Photovoltaic 0.38 6.5 0.020Hydraulic dam 0.01 1.28 0.001

Primary energy (non-renewable)

Primary energy

(renewable)

CO2 emissions

MJ primary /MJ final

MJ primary / MJ final

kg CO2 / MJ final

Hard Coal (anthracite or bituminous)

Soft Coal (sub-bituminous or lignite)

Source: EcoInvent Database

What is in coal-generated electricity?

110 times more Particulates per kWh compared to natural gas

23 times more SO2 per kWh

16 times more mercury per kWh (380 kg/yr for a 1000 MW plant)

radioactive trace elements

Coal is 1-10 ppm Uranium, 2.5-25 ppm Thorium

Uranium energy density in coal is 25% the energy density of coal! Sources: EcoInvent and A. Gabbard, ORNL

Uses: transport

Energy used for transport (IEA)

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500000

1000000

1500000

2000000

2500000

Kilo

Tonn

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t (kt

oe)

Electricity

Combustible Renewables and Waste

Natural Gas

Petroleum Products

Coal and Coal Products

Transportation

Growing energy use for transportation worldwide.

Principally based on petroleum products

Generally two types of transportation:

1) Electric grid + rail or road (tram, train, buses)

2) Liquid fuel-based– kerosene + airports: planes,– diesel + ports: ships– gasoline + diesel + highways + parking: cars,

trucks, buses

3)Animal or human powered.

Metrics for transportationPersonal transportation: passenger*kilometre

Freight transportation: tonne*kilometre

Source OECD 1996

Primary energy cost of passenger transport

Transport mode Primary energy CO2 emittedMJ / p-km kg / p-km

Plane 9.83 0.36Car 3.25 0.18Bus 1.87 0.11

Train 1.06 0.06

Source EcoInvent Database

Primary energy cost of freight transport

Transport mode Primary energy CO2 emittedMJ / t-km kg / t-km

Plane 17.71 1.1116tonne truck 6.13 0.3532tonne truck 2.81 0.16

Train 0.75 0.04Barge 0.65 0.04

Ocean Tanker 0.09 0.01

Source EcoInvent Database

0.036

0.044

0.005

The global carbon cycle

What happens when we burn so much fossil fuels?

Climate change in the past

Source T. Stocker 2005

current level 380 ppm

(Can extend graph to 850'000, T. Stocker 2006)

Homo Sapiens appears

Agriculture begins

Climate change in the present

CO2 and energy carriers

Source: J. Siirola, GRC 2006

Causes of CO2 increase in atmosphere

Volcanoes ?

Agriculture / deforestation ?

Burning biomass ?

Burning fossil fuels ?

Sun-driven global warming?

at 380 ppm, CO2 in atmosphere corresponds to 730 GigaTonnes Carbon (GTC)

or 2650 GigaTonnes CO2 (GTCO2)(3.664 factor between CO2 and C)

a 30% increase since 1900.

Source: J. Siirola, GRC 2006

Remember CO2 in atmosphere is

currently 730 GTC!

CO2 content of proved fossil reserves

FUEL Reserves Production Consumption

Units tonnes CO2 percent tonnes CO2 tonnes CO2Oil 7.01E+011 26.45% 1.21E+010 1.19E+010

Anthracite 1.32E+012lignite 1.45E+012Coal 2.77E+012 104.49% 1.66E+010 1.69E+010Gas 3.41E+011 12.88% 5.25E+009 5.22E+009

Total 3.81E+012 143.82% 3.40E+010 3.40E+010

Proportion to current CO2 in

atmosphere

Source for proven reserves: BP Statistical Review of World Energy 2006

CO2 in atmosphere at 380 ppm: 2.65e12 tonnes

Food

A few facts about food

In Switzerland, fossil primary energy spent on food is estimated to be 34 GJ/person/year

Fossil primary energy spent on private transportation is 42 GJ/person/year

An average person eats 4.75 GJ/person/year in nutritional calories

Primary fossil / nutritional energy = 7

Source: Keanzig et Jolliet 2006, Consommation respectueuse de l'environnement, Rapport pour l'OFEV

Swiss agriculture and climate change

Source BLW, Rapport Agricole 2003

Agriculture and climate change (2)


Methane et Nitrous oxide

Methane = CH4

(natural gas) 8% of CO

2-eq. in Switz., of which 63% from agriculture

1 kg CH4 = 21 kg CO

2-eq.

In agriculture, methane comes from animal digestion and organic fertilizer.

Nitrous oxide = N2O

7% of CO2-eq in Switz., of which 72% from agriculture

1 kg N2O = 310 kg CO

2-eq.

Soil processes and various fertilizer.

Agriculture world-wide has emitted as many greenhouse gases as fossil fuel burning since 1900. Livestock world-wide emits as much GHG/yr as global transport. (Source: FAO 2006, Livestock’s long shadow)

8


Cause of the reduction of Swiss agricultural methane


ConséquencePlus de farines animales: donc fourrage importé:

Dont soja du Brésil et de l'Argentine (déforestation, perte de biodiversité)


Example of an industrial symbiosis with a bad ending …

Feeding animals with animal remains

Result: Spongiform encephalitis – Mad cow disease.

Soybean in Brazil

Source M. Shean, United States Department of Agriculture, 2004

Soybean area in Brazil (2)

Source M. Shean, United States Department of Agriculture, 2004

Documents

Energy carriers