Urban Energy Systems:
Challenges & Opportunities
Arnulf Grubler
IIASA and Yale University
GEA Chapter 18 Urban Energy Systems
Main Messages
1. The world is already today predominantly urban (~3/4 of final energy)
2. Rural populations are likely to peak at 3.5 billion and decline after 2020
(all long-term energy growth will be urban)
3. City dwellers have often lower direct energy and carbon footprints
4. Important deficits in urban energy and carbon accounting
(embodied energy, import/export balance) jeopardize effective policies
5. Cities have specific sustainability challenges & opportunities
(high density enables demand/supply management but calls for
low waste/~zero-impact systems)
6. Vast improvement potentials (>x2), but most require management of
urban form and systemic change (recycling, cascading, energytransport, land-use-transport systems integration,..)
7. Governance Paradox:
- largest leverage from systemic change,
- but requires overcoming policy fragmentation
and dispersed, uncoordinated decision taking
www.globalenergyassessment.org
© GEA 2012
2
Millions
Population by Settlement Type/Size
10000
10,000,000 and more
9000
5,000000 to 10,000,000
8000
1,000,000 to 5,000,000
7000
100,000 to 1,000,000
6000
Less than 100,000
Rural
5000
Number of
agglomerations
in 2005
13
30
340
3192
??
4000
3000
2000
1000
0
1950 1960 1970 1980 1990 2000 2010 2020 2030 2040 2050
© GEA 2012
www.globalenergyassessment.org
growth
dominated
by small &
medium sized
cities!
3
GEA Chapter 18 Urban Energy Systems
Main Messages
1. The world is already today predominantly urban (~3/4 of final energy)
2. Rural populations are likely to peak at 3.5 billion and decline after 2020
(all long-term energy growth will be urban)
3. City dwellers have often lower direct energy and carbon footprints
4. Important deficits in urban energy and carbon accounting
(embodied energy, import/export balance) jeopardize effective policies
5. Cities have specific sustainability challenges & opportunities
(high density enables demand/supply management but calls for
low waste/~zero-impact systems)
6. Vast improvement potentials (>x2), but most require management of
urban form and systemic change (recycling, cascading, energytransport, land-use-transport systems integration,..)
7. Governance Paradox:
- largest leverage from systemic change,
- but requires overcoming policy fragmentation
and dispersed, uncoordinated decision taking
www.globalenergyassessment.org
© GEA 2012
4
Annex-I: Per Capita Urban Direct Final Energy
red= above national average, blue = below national average
n=132
© GEA 2012
www.globalenergyassessment.org
5
Non-Annex-I: Per Capita Urban Direct Final Energy
red= above national average, blue = below national average
n=68
© GEA 2012
www.globalenergyassessment.org
6
Direct and Embodied Urban Energy
Energy Use (EJ)
4.0
3.5
Embodied
3.0
Direct
2.5
2.0
1.5
1.0
0.5
0.0
Tokyo (90)
© GEA 2012
Tokyo (95)
Beijing (92)
Beijing (97)
Shanghai
(92)
www.globalenergyassessment.org
Shanghai
(97)
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GEA Chapter 18 Urban Energy Systems
Main Messages
1. The world is already today predominantly urban (~3/4 of final energy)
2. Rural populations are likely to peak at 3.5 billion and decline after 2020
(all long-term energy growth will be urban)
3. City dwellers have often lower direct energy and carbon footprints
4. Important deficits in urban energy and carbon accounting
(embodied energy, import/export balance) jeopardize effective policies
5. Cities have specific sustainability challenges & opportunities
(high density enables demand/supply management but calls for
low waste/~zero-impact systems)
6. Vast improvement potentials (>x2), but most require management of
urban form and systemic change (recycling, cascading, energytransport, land-use-transport systems integration,..)
7. Governance Paradox:
- largest leverage from systemic change,
- but requires overcoming policy fragmentation
and dispersed, uncoordinated decision taking
www.globalenergyassessment.org
© GEA 2012
8
China - Air Pollution (SO2) Exposure
East China (2000)
Tg SO2 x
million people
3.3
Hong Kong
1.9
3.4
Shanghai
0.3
2.1
1.8
Beijing
1.4
1.7
0.6
© GEA 2012
www.globalenergyassessment.org
9
Re
ne
w
Heat, Liquids
.Gas
ab
le
s
Energy and and
ExergyExergy
Flows Vienna
2007
Urban Energy
Efficiency
Electricity
Secondary Energy: 43 TWh 100%
Motor fuels
Secondary Exergy: 163 PJ 100%
solids
district heat
Vienna 2007
Final Energy:
37 TWh 85%
Final Exergy: 136 PJ
83%
Useful Exergy: 28 PJ
17%
Industry
Households
L.T. heat
Services
Process
heat
Traffic
Light, motion
Losses
Useful Energy:
21 TWh 50%
Source: Wien Energie, 2009; (rough) exergy efficiencies based on Gilli et al., 1996.
Geneva (CH)
Vienna (A)
Malmo (S)
London (UK)
© GEA 2012
Useful exergy as % of
secondary
primary
23.2
15.5
17.2
21.2
12.7
11.3
6.2
www.globalenergyassessment.org
trad.
Mexican village
5.7
10
GEA Chapter 18 Urban Energy Systems
Main Messages
1. The world is already today predominantly urban (~3/4 of final energy)
2. Rural populations are likely to peak at 3.5 billion and decline after 2020
(all long-term energy growth will be urban)
3. City dwellers have often lower direct energy and carbon footprints
4. Important deficits in urban energy and carbon accounting
(embodied energy, import/export balance) jeopardize effective policies
5. Cities have specific sustainability challenges & opportunities
(high density enables demand/supply management but calls for
low waste/~zero-impact systems)
6. Vast improvement potentials (>x2), but most require management of
urban form and systemic change (recycling, cascading, energytransport, land-use-transport systems integration,..)
7. Governance Paradox:
- largest leverage from systemic change,
- but requires overcoming policy fragmentation
and dispersed, uncoordinated decision taking
© GEA 2012
www.globalenergyassessment.org
11
Stylized Hierarchy in Urban Energy/GHG
1.
2.
3.
4.
5.
6.
Decreasing order
of importance
© GEA 2012
7.
Spatial division of labor
(trade, industry structure, bunkers)
Income (consumption)
Efficiency of energy end-use
(buildings, processes,
vehicles, appliances)
Urban form
(density↔public transport↔car
ownership↔functional mix)
Fuel substitution (imports)
Energy systems integration
(co-generation, heat-cascading)
Urban renewables
Increasing level of
urban policy leverage
www.globalenergyassessment.org
12
SynCity Urban Policy Leverages
Medium to
814 Energy Systems
high density
Analysis
© GEA 2012
Arnulf Grubler
www.globalenergyassessment.org
13
GEA Chapter 18 Urban Energy Systems
Main Messages
1. The world is already today predominantly urban (~3/4 of final energy)
2. Rural populations are likely to peak at 3.5 billion and decline after 2020
(all long-term energy growth will be urban)
3. City dwellers have often lower direct energy and carbon footprints
4. Important deficits in urban energy and carbon accounting
(embodied energy, import/export balance) jeopardize effective policies
5. Cities have specific sustainability challenges & opportunities
(high density enables demand/supply management but calls for
low waste/~zero-impact systems)
6. Vast improvement potentials (>x2), but most require management of
urban form and systemic change (recycling, cascading, energytransport, land-use-transport systems integration,..)
7. Governance Paradox:
- largest leverage from systemic change,
- but requires overcoming policy fragmentation
and dispersed, uncoordinated decision taking
© GEA 2012
www.globalenergyassessment.org
14
GEA Chapter 18 Urban Energy Systems
Lead Authors:
Xuemei Bai, Thomas Buettner, Shobhakar Dhakal, David J. Fisk, Arnulf Grubler (CLA),
Toshiaki Ichinose, James Keirstead, Gerd Sammer, David Satterthwaite,
Niels B. Schulz, Nilay Shah, Julia Steinberger, Helga Weisz
Contributing Authors:
Gilbert Ahamer*, Timothy Baynes*, Daniel Curtis*, Michael Doherty, Nick Eyre*, Junichi Fujino*,
Keisuke Hanaki, Mikiko Kainuma*, Shinji Kaneko, Manfred Lenzen, Jacqui Meyers,
Hitomi Nakanishi, Victoria Novikova*, Krishnan S. Rajan, Seongwon Seo*,
Ram Manohar Shrestha*, P.R. Shukla*, Alice Sverdlik
(*Contributors to GEA KM18 city energy data base)
Resources:
Online: www.globalenergyassessment.org
Chapter 18 (main text)
Supporting material: GEA KM18 working papers and city energy data base
A. Grubler and D. Fisk (eds), Energizing Sustainable Cities:
Assessing Urban Energy, Earthscan (2012)