PSE 104 Section 2: Lecture 11 I. Overview of Energy Sources A. A. Energy units “primer” 1. 1. Energy expressed as a finite quantity Joule (J) = SI

PSE 104 Section 2: Lecture 1 1

I. Overview of Energy Sources

A. Energy units “primer”1. Energy expressed as a finite

quantity Joule (J) = SI unit of energy British Thermal Unit (Btu) = English

unit of energy 1 Btu is the energy required to

raise the temperature of 1 lbm of water 1° F @ 68° F

1000 J = 1 kJ; 1 Btu = 1.055 kJ



A. Energy units primer 1 calorie is the energy required to

raise the temperature of 1 g of water 1° C @ 15° C

1 calorie (cal) = 4.187 Joules 1 Calorie (nutritionally) = 1000 cal (1

kcal) 1 electron volt (eV) = 1.60 x 10-19 Joule

Mass quantities1 metric ton (tonne) = 1000 kg1 domestic ton = 2235 lb1 short ton - 2000 lb



A. Energy units primer HUGE numbers are necessary for

quantifying both national and international energy use!

Mega (M) 106

Giga (G) 109

Tera (T) 1012

Peta (P) 1015

Exa (E) 1018

1 “quad” 1015 Btu



A. Energy units primer2. Energy expressed as a rate

Rate of energy = energy per unit time = Power

Watt (W) = SI unit of power; 1 W = 1 Joule/sec

1000 Joule/sec = 1 kW 1 kilowatt-hour (kWh) = 1 kW over 1

hour time (finite amount) = 3600 kJ Horsepower (hp) = English unit of

power; 1 hp = 0.7068 Btu/sec 1 hp = 0.764 kW



A. Energy units primer3. Other useful energy quantities

Natural gas: 1 therm = 100,000 Btu = 1 x 105 Btu = 1.055 x 105 kJ

Air conditioning and refrigeration: 1 ton of refrigeration = 200 Btu/min = 12,000 Btu/hr

1 ton coal equivalent (tce) = 28 GJ = 28,000 MJ

1 ton oil equivalent (toe) = 42 GJ = 42,000 MJ



B. Fossil fuels overview1. Crude Oil

What exactly is it??? Complex mixture of hydrocarbons

Hydrocarbons are compounds with only hydrogen and carbon atoms (C & H)

example: C1-C2-C3-C4-C5-C6-C7-C8 = C8 total (+ H’s)

Often called “paraffins” by organic chemists

Elemental composition: 85% Carbon, 14% Hydrogen, 1% other


I. Overview of Energy SourcesB. Fossil fuels overview

1. Crude Oil1. Complexity comes from a large range of

molecular weights (MW): CC2727 - C - C35 35

2.2. Over 500 different HC compounds!Over 500 different HC compounds!

3.3. Most crude oil formed about 500 million Most crude oil formed about 500 million years agoyears ago

4. Energy is liberated by breaking of C-H bonds principally through combustion

5. Combustion is a chemical reaction which is technically oxidation: the reaction of oxygen with a fuel

6. Average energy density: 42 MJ/kg = GJ/tonne



B. Fossil fuels overview Specialized products from crude

oil1. Gasoline (“petrol”)

Still a mixture of hydrocarbons: C4 - C12

On average C8H18 - octane Average energy density: 44 MJ/kg = GJ/tonne

2. Diesel fuel Mixture of hydrocarbons: C8 - C16

On average C12H26 - dodecane More of an “oil” than gasoline Average energy density: 45 MJ/kg = GJ/tonne



B. Fossil fuels overview Emissions from gasoline and

diesel Unburnt hydrocarbons (HC’s) Nitrogen oxides: NOx

Sulfur oxides: SOx

SO2 + water Sulfurous acid “acid rain”

Carbon dioxide: CO2

Ozone: O3

Lead: Pb (earlier times)



B. Fossil fuels overview2. Natural gas

2. What exactly is it??? Principally methane: CH4

3. Elemental composition: 75% C, 25% H4. Energy density: 55.1 MJ/kg5. Unlike oil, natural gas is a pure compound6. Extremely clean fuel: CH4 + 2O2 CO2 + H2O +

HEAT• Most valuable of all fossil fuels• LNG = liquified natural gas

• Cheaper to transport• Closely related fuel gas: Propane: C3H8



B. Fossil fuels overview3. Coal

What exactly is it??? Mostly carbon (C), but highly variable: 60% - 92% carbon

Also contains oxygen, hydrogen, sulfur, and nitrogen

Sulfur contamination: results in acid rain; e.g. coal-fired power plants in NE United States

Average energy density: 30 MJ/kg



B. Fossil fuels overview3. Coal - chemical composition

Several different forms (actually 8)1. Anthracite: “hard coal”2. Lignite: “soft coal”

Anthracite Lignite

Carbon 92% 60-75%

Oxygen 2.5% 17 - 34%

Hydrogen 3.75% 6%

Sulfur 1% 0.5 - 3%



B. Fossil fuels overview4. Tar Sands and Oil Shale

a. “Tar sands” Bitumen coated sand deposits Deposits can be mined and processed Oil is extracted with heat and steam Economical when crude oil >$60 per

barrell Ft. McMurray in Alberta, Canada has some

of the world’s largest deposits Canada is large exporter to USA (along

with regular crude and natural gas)



B. Fossil fuels overview4. Tar Sands and Oil Shale

a. “Oil Shale” Literally oil impregnated rock (shale) Somewhat like coal Also called Also called kerogenskerogens First discovered in NW Colorado -

“burnable rock” Expensive to extract and environmentally

problematic - huge strip mines



B. Fossil fuels overviewSummary of fossil fuels energy density:

1. Crude Oil: 42 MJ/kg2. Natural Gas: 55 MJ/kg3. Coal: 28 MJ/kg_____________________1. Wood ???



C. Energy consumption and supply1. World energy 2005 Global energy consumption: 463

Quads = 488.5 EJ Average of 72.6 million

Btu/person/year However,

Developed countries: >150 Btu/person/year Developing countries: < 40 Btu/person/year


PSE 201 Lecture 6 17024839-2

Projected World Supplies

19001900 19201920 19401940 19601960 19801980 20002000 20202020 20402040 20602060 20802080 3000

2020

4040

6060

8080

100100100 BILLION

BARRELS

Billion Barrels of Oil

Equivalent per Year (GBOE)

Billion Barrels of Oil

Equivalent per Year (GBOE) Natural

GasNatural

Gas

HydroelectricHydroelectric

Crude OilCrude Oil

Solar, Wind Geothermal

Nuclear Electric

1993

CoalCoal

Decreasing

Decreasing

Fossil F

uelsF

ossil Fuels

Ne

w T

echno

logies

Ne

w T

echno

logies

World Energy DemandWorld Energy Demand

after Edwards,AAPG 8/97

tar sands; oil shale

2009=NOW



C. Energy consumption and supply1. World energy Large international disparity in energy

availability and use! “haves” and “have nots”

KEY POINT: expected large (exponential) population increases in “developing” countries will place a large strain on energy supply in the future

Energy efficiency of “developing” countries lags far behind N. America and Europe




Crude Oil Prices: 1970 - 2000Crude Oil Prices: 1970 - 2000


Crude Oil Prices 1860 - 1996Crude Oil Prices 1860 - 1996

Crude Oil Prices 1860 - 1996

0

5

10

15

20

25

30

35

40

2008

$100+



C. Energy consumption and supply2. US energy 2005 US energy consumption: 100 quads

= 106 EJ This is about 22% of global energy

consumption Average of 340 million Btu/person/year However, US has < 5% of world’s

population! Large reason for our extremely high

standard of living…




I. Overview of Energy SourcesC. Energy consumption and supply

2. US energyExample: United States: United States: 94709470 kWh/person/year kWh/person/year

vs. vs. Germany: Germany: 32703270 kWh/person/year kWh/person/year

Clearly, US per capita energy usage Clearly, US per capita energy usage not necessary for a high standard not necessary for a high standard of living…of living…



C. Energy consumption and supplyKey energy consumption quantities:1. Energy Intensity =

High = low energy use efficiency (e.g. Africa)

Low = high energy use efficiency (e.g. US)

2. Energy per capita =

Strongly affected by energy efficiency

€

Energy Units

$ GDP

€

Energy Units

Population





C. Energy consumption and supply2. US energy - crude oil US crude oil production: 1970: 9.6 MM bpd 2006: 5.1 MM bpd

NOW, 2/3 of all crude oil is imported

2005: 20.8 MM bpd Canada, Middle East,

Mexico,Venezuela





C. Energy consumption and supply2. US energy - transportation 70% of all oil in US is used

for transportation purposes Some relief expected due to

growing biofuels availability and hybrid and electric cars

Petroleum will continue to be the dominant source of transportation fuels for next 20-30 years


II. World Energy Consumption and II. World Energy Consumption and SupplySupply


II. World Energy Consumption and II. World Energy Consumption and SupplySupplyUS Electricity Generation


III. Renewable Energy Sources III. Renewable Energy Sources OverviewOverviewA. Solar-derived sources

1. Direct solar heating and electricity generation

2. Biomass energy - fuel value of biomass

3. Wind power - solar heating of atmosphere

4. Hydroelectric power - solar origin of weather and rainfall

5. Tidal energy - gravitational effect of sun (and moon)


III. Renewable Energy Sources III. Renewable Energy Sources OverviewOverviewB. Non-solar derived sources

1. Geothermal energy - heat from earth’s core


Other Energy SourcesOther Energy Sources

C. Nuclear power Environmental and safety issues,

but most efficient, non-polluting, and essentially inexhaustible source of large-scale power generation

Neither solar, geothermal, or fossil fuel derived source

Energy contained within atoms - fission and fusion


Other Energy SourcesOther Energy Sources

C. Nuclear power 80% of electricity generation in

France is nuclear 20% of electricity generation in

US is nuclear Building consensus that nuclear

power must be a more significant part of US electricity generation for the future - renewables “can’t do it all”

Documents

PSE 104 Section 2: Lecture 11 I. Overview of Energy Sources A. A. Energy units “primer” 1. 1. Energy expressed as a finite quantity Joule (J) = SI