Our High-Energy Society Version 11: Sep 3, 2014

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Our High-Energy
Society
[email protected]
Version 11: Sep 3, 2014
For Econ 310 fall 2014
Take-homes for energy economics
• Humans only convert energy from one form to another
– Electricity and hydrogen are energy carriers, not “sources”
– People want specific energy services at particular times
– Timing is important, especially for electricity, so storage is
a big deal
• Useful energy is lost with each conversion
• Energy services = energy + capital
– Energy is “intermediate good” with “derived demand”
– Capital is durable so energy systems change slowly
• Power (watts) is the rate at which energy is converted
2
Order of topics
1.
2.
3.
4.
5.
6.
Basics – physics, energy services, units
Power = rate of energy conversion
Historical trends
Energy Intensity of the economy
[So what – energy & human welfare]
The future
3
1. Basics
Optional Energy: What is It - physics?
• Ability to do Work
– (formal physics definition)
• Work = Force x distance
– Mass x acceleration x distance
– Kg x [meters / sec]/sec x meters
– Kg-m^2/sec^2
• The Newton: 1 N = 1 kg-m/sec^2
• Newton-meter = 1 kg-m^2/sec^2
• 1 Joule = 1 J = 1 Newton-meter
5
Energy + Capital = Energy Services
• We have “End Use” demands for energy
services:
– Food + mitochondria = ATP -> maintain life
– Oil + furnace = Warmth
– Electricity + speaker = Sound (speaker)
– Gasoline + automobile = Mobility (a passengerkilometer)
– Electricity + LED lamp = Light
6
What Forms does it Take?
• Chemical bonds – most common form traded
in markets (why?)
– Bagel, gasoline
• Electricity – flow of electrons
• Heat / Pressure
– Warm room, hot water, steam
• Mass (E=Mc2)
– Sun, nuclear bomb, nuclear reactor
7
First Law of Thermodynamics
• Energy is converted from one form to another
– (relativity: mass is a form of energy)
• Example: Your Toaster
– Natural gas ->Electricity->Heat->(toast + warmth)
8
9
Implication of First Law:
• Electricity is not an energy source
– It’s an energy “currency”
– It’s an energy “carrier”
• Hydrogen is not an energy source
– It’s an energy currency
– It’s an energy “carrier”
• If hydrogen is the answer, where do we get
the hydrogen?
10
Second Law of Thermodynamics:
• Energy is degraded with every conversion, and ends
up as low-grade heat
• Energy conversions are never 100% efficient
– and usually not even close
• Energy is lost as heat at every step
• Much harder to extract useful energy from a
room-full of low-grade heated air than from a
gas flame or electric current
11
Efficiencies Vary: we
cannot say that all
lost heat is “waste” –
at least not from
economic
perspective-Incandescent light
bulb was huge
improvement over
kerosene lamp
12
13
Measuring Energy – Common Units
• Btu – British thermal unit
– 1 lb water heated up by 1 degree f
• kWh – kilowatt hour
– Used for electricity – 1 kWh costs 10 cents in
Anchorage
14
Example: Bagel
• 300 food calories =300 kcal
• x [1000 cal/kcal] = 3E+5 cal
• x [4 joules/cal] = 1.2E+6 joules
15
2. Power
Power: the Rate of Energy Conversion
– Just as speed = distance per unit of time,
– Miles per hour
• Power = Energy conversion per unit of time
• Measured as Watts (W)
– 60-watt light bulb converts electricity to light (and
heat!)…
– But only while it is on!
– 1W = one joule per second
17
Power = rate of flow of energy
• Solar Energy flows through natural systems
• Energy flows through human
techno-economic systems, too
• Storage & retrieval is always costly
18
Energy flow:
Solar Radiation received at Earth’s surface:
at the average rate of about 150 watts per square meter
19
Power: other Examples
• Human (at rest)
– About 100 W (we are always on!)
• Hair dryer
–
–
–
–
1,000 W = 1 kilowatt = 1 kW (when on!)
If it is on for one hour it uses:
1 kW x 1 hour = 1 kilowatt-hour (1 kWh)
(costs 10 cents)
• Large-ish windmill
– 1 MW = 1 Megawatt = 1 million watts
• Large power plant
– 1 GW = 1 Gigawatt = 1,000 MW = 1 billion W
20
Conversion Example: Jet Engine
Forms:
Chemical -> Heat ->
Motion
Power output of ONE
engine:
15 Megawatts during
take-off
60 MW for the airplane
Compare to average
electricity demand of
Anchorage: about 240
21
Megawatts
Jet engine vs Sailing ship
The clipper ship
could generate
about 490
kilowatts from
the wind
=490 kW=3% of
the 747 jet
engine
Source: Smil 1994
22
Optional Power: Horse vs. Hairdryer
• Horsepower = .67 kW = 670 watts
– invented by James Watt so he could charge for
steam power in a way people could understand
– Few horses can actually produce 1 hp
23
3. Historical perspectives
24
Pre-Industrial “Prime Movers” ~1300 BCE
Source: Smil 1994
25
Beasts of burden
26
50-Ton Statue on the Move
Source: Smil 1994
27
Greek Tireme Galley
Source: Smil 1994
28
Pre-Industrial Energy Sources
Source: Smil 1994
29
Pre-Industrial Energy Sources
Source: Smil 1994
30
Horizontal Waterwheel 1588
Source: Smil 1994
31
Overshot Waterwheel 1770
Source: Smil 1994
32
French Windmill
1770
Source: Smil 1994
33
Wood: The Typical Colonial American
Farmhouse….
• Burned 30 cords of wood per year
• Needed 30 acres of woodlot
34
Meanwhile, Under the Earth’s
Surface……..
35
Formation of Fossil Fuels
Formation took millions of
years…
Extraction began during
past 2,000 years
Large-scale extraction
began with steam engine
(1788), liquid petroleum
(1859)
36
Why was the Steam Engine
invented?
Source: Smil 1994
37
Big Dams built by Federal Govt
Hoover Dam (1935)
produces about
1,000 Megawatts of
power – about twice
as much as peak
demand in all of
Alaska
38
First Commercial Nuclear Plant: 1956
Calder Hall, U.K.
4 reactors, each 23 MW
(each reactor Only 50%
more power than jet
engine…entire plant only
50% more powerful than
747 on take-off)
39
The Global energy mix
• Given 50-100 years, the energy system has
consistently revolutionized itself
40
Figure 1. World Energy Consumption by Source, Based on Vaclav Smil
estimates from Energy Transitions: History, Requirements and
Prospects together with BP Statistical Data for 1965 and subsequent
Avg annual growth
= (550/20)^(1/190) – 1
= 0.018 = 1.8%
http://ourfiniteworld.com/2012/03/12/world-energyconsumption-since-1820-in-charts/
41
Changing Mix of World Primary
Energy “Sources” through 2000
Oil & Gas Journal 26 Jan 2004 p 19
42
Changing Mix of World Primary Energy
“Sources” through 2010 and projected 2030
2000-2010 and 2011-2030 (est.) BP Stat Review “Outlook
to 2030”. Renewables does not include hydro – it is wind,
solar, geothermal, tidal/wave
43
Changing Prime Movers
IC engine
steam turbine
Source: Smil 1994
44
United States Energy Mix
EIA Total Energy – 10Apr 2014
http://www.eia.gov/totalenergy/
Referencing Annual Energy Outlook
45
Shares of total primary energy consumed
Power plants
shift from coal
to natural gas
Renewables
rising
46
4. Energy Intensity
Energy Intensity
• Total energy / Total GDP
– Data from EIA
http://www.eia.gov/totalenergy/data/annual/pers
pectives.cfm
– Example:
Energy (10^15 Btu)
GDP (10^12 $2005)
Intensity (Btu/$2005)
1949
32
1,843
17.4
2011
97
13,315
7.3
Explore at:
http://yearbook.enerdata.net/#energy-intensity-GDP-by-region.html
48
20
18
Thousand Btu per Real (2005) Dollar¹
16
14
12
10
8
6
4
2
0
1949 1952 1955 1958 1961 1964 1967 1970 1973 1976 1979 1982 1985 1988 1991 1994 1997 2000 2003 2006 2009
49
U.S. Energy Intensity update:
March 2013
Different units (!)
50
Energy intensity falling worldwide…
U.S. economy is de-coupling itself from energy
(declining energy intensity) and de-carbonizing a bit
(switch to natural gas and renewables)
52
US energy consumption
per capita has been flat for
40 years – but that’s
different than flat TOTAL
consumption…
source Metcalf 2007
53
5. So What:
Energy use and Human Well-being
54
Energy Use vs. Human Development
The Human
Development Index
combines life
expectancy,
education, and
income into an index
that ranges from zero
to 1
Data as of 2001, source: Smil 2003
55
Energy Use vs Infant Mortality
Data as of 2001, source: Smil 2003
56
Future
Future:
World energy use currently growing by
Primary energy2.5%/yr
world consumption
BP Statistical Review of World Energy
2012
© BP 2012
6. The Future
Future
• Useful decomposition:
• Impact = Population x Affluence x Technology
– “IPAT” : I = P x A x T
– “Balance of forces” approach to sustainability
• Total Energy = P x [$GDP/person]x [Energy/$GDP]
• [Energy/$GDP] = energy intensity
– Has been falling
• But GDP$/person is rocketing up in Asia
60
North America: The balance of forces is
pushing TOTAL Energy flat and Total CO2
emissions down (!)
Good news from US & N America
Total energy use flat or declining (!)
62
World: Balance of forces, driven by
GDP per capita, leads to increasing
projected energy use
BP Energy Outlook 2030
63
Good news for world?
64
Energy growth coming from poor countries
OECD = “Organization for Economic Cooperation and
Development” – basically the rich countries
65
Renewables are increasing worldwide, but from small base
Renewable energy consumption/share of power by region
Other renewables consumption by region
Other renewables share of power generation by region
Million tonnes oil equivalent
Percentage
BP Statistical Review of World Energy
2013
© BP 2013
Global CO2 Emissions: two different stories
Data through
2010, 2010-2030
is a projection by
BP
67
Take-homes for energy economics
• Humans only convert energy from one form to
another
– People want specific energy services at particular
times
– Timing is important, especially for electricity, so
storage is a big deal
• Energy services = energy + capital
– Energy is “intermediate good” with “derived demand”
– Capital is durable so energy systems change slowly
• Useful energy is lost with each conversion
• Power (watts) is the rate at which energy is
converted
68
References (partial)
• Hansen, James. Defusing the Global Time Bomb. Scientific American,
February 2004. Pp. 68-77.
• Lovins A.B. Scientific American, Sep 2005
• Smil, Vaclav. 1994 Energy in World History. Westview.
• Smil, Vaclav. 2003. Energy at the Crossroads. MIT Press.
• Scott Brennan and Jay Withgott. 2003. Environment: The Science Behind
the Stories. Pearson/Cummings.
• BP Statistical Review of World Energy. Various years. online.
69
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