the water-energy nexus in global context
TRANSCRIPT
The Water-Energy Nexus in Global Context
Christopher A. Scott 1,2
Zachary Sugg 1
1
2
Overview & Science-Policy Questions
• Water implications of future power generation? • Water-energy assessments either global (EIA, IEA,
Maheu 2009) or country-level (data permitting). • Here, U.S. Energy Info. Administration (EIA) country-
level electricity generation data, 1980-2007: – Identify potential future electricity production trends to
construct water-energy use scenarios. – Facilitate cross-country comparisons – Evaluate hot spot countries likely to experience acute
water-energy tradeoffs, and identify avenues for exploring the nature of those tradeoffs.
0%
2%
4%
6%
8%
10%
12%
14%
US Canada China India Brazil Saudi Arabia Mexico Russia
Compound Annual Growth, Conventional Generation: 1998-2007
Slight increases in renewables, but no indication that water-extractive/consumptive conventional thermal generation will stop increasing. This will continue to place a demand on available water supplies.
Fossil Fuel Thermoelectric Power Generation, 1998-2007
Key trends - global electricity production • Electricity demand to double, 2005-2030 (Maheu,
2009) – Non-OECD demand to increase 84%; OECD 14%
• Generation to increase 87%, 2010-2035 (EIA, 2010) – Hydroelectricity (reservoir evaporation) highest energy
nexus water consumption but low adoption of new hydropower (Maheu, 2009). Brazil?
– Fossil fuel generation next level water consumption; share of renewables continues to rise
• Global energy price increases, government incentives, and GHG mitigation = interest in nuclear and renewables. Fukushima effect?
• Renewables long-term prospects excellent
Water intensities of generation
Source: Scott and Pasqualetti, 2010
2007 Baseline Electricity Generation
portfolios
S. American countries and Canada highly
reliant on hydropower.
How do these broader scale trends vary among countries in the Americas? Last 10 years saw growth in renewables and hydropower in S. American countries, Renewable energy production in the Americas is on the rise in several countries, both hydroelectric and non-hydro.
The U.S. and China will remain by far the biggest producers of thermal electric power. However, based on recent growth rates, several Central and South American nations are likely to experience substantial increases in thermal power generation by 2017 relative to the 2007 baseline.
Potential Energy Future Portfolios
Brazil • Huge amount of hydropower, with dam sites possible for more. Potentially vulnerable to altered rainfall regime due to GCC.
• Bioenergy typically a major consumer of water, but Brazilian ethanol primarily from sugar cane is rain fed. (de Fraiture et al., 2008)
• Assuming recent growth rates continue, fossil fuel electricity generation could potentially increase by 145% by 2017.
Nuclear 3% Conventional
Thermo 8%
Non-hydro Renewables
4%
Hydroelectric 85%
Brazil Electricity Generation Portfolio 2007
Nuclear 8%
Conventional Thermo
14%
Non-hydro Renewables
6% Hydroelectric
72%
Brazil Energy Generation Portfolio – Projected 2017
Nuclear in Brazil: high water consumption
Several countries showed positive growth in nuclear capacity in recent years, but Brazil by far the most rapid recent growth in nuclear thermo electric generation in the Americas. Roughly the same capacity as India.
Based on CAGR 1997-2008 and total generation for 2008
Country Compound Annual Growth
Rate 1997-2008 Total Capacity,
BkWh
Brazil 16% 14
China 19% 65
Russia 5% 152
South Korea 5% 143
Czech Republic 8% 25
India 5% 13
U.S.A. 2% 806
Canada 3% 89
Brazil: Key future tradeoff questions
• Will growth in hydropower capacity continue?
• Will growth in nuclear revive?
• If neither, how much will fossil fuel electricity sources have to increase to meet demand?
• How will energy policy be driven by climate/carbon considerations? Implications for fossil/non-fossil mix?
• Every scenario and future portfolio has energy-water tradeoffs related to spatial distribution of water supplies and water withdrawal and consumption intensities of each technology.
• Biofuels currently for ethanol. What future biodiesel? Water (irrigation) implications?
Chile
Nuclear 0%
Conventional Thermo
58%
Non-hydro Renewables
5%
Hydroelectric 37%
Chile Electricity Generation Portfolio
Nuclear 0%
Conventional Thermo
57%
Non-hydro Renewables
17%
Hydroelectric 26%
Chile Electricity Generation Portfolio – Projected 2017
• Hydro share of total electricity to decrease (but net hydro increase); other renewables increase • Chilean government pursuit and approval of controversial Patagonia hydro project* • How much could contentious hydropower development be offset by renewable energy? • What tradeoffs between water/environmental and hydropower when the electricity sector legally
over-rides the water sector? (Bauer, 2009) • How might increasing control of river systems through hydropower infrastructure and reservoir
creation increase vulnerability to altered hydrologic cycle due to climate change? “Build first, ask questions later” (Bauer, 2009 p. 649)
*http://www.guardian.co.uk/environment/2011/may/10/chile-hydroelectric-dam *http://www.guardian.co.uk/environment/2011/may/10/chile-patagonia-dams-hydroelectricity
Argentina Nuclear
6%
Conventional Thermo
65%
Non-hydro Renewables
1%
Hydroelectric 28%
Argentina Energy Generation Portfolio 2007
Nuclear 4%
Conventional Thermo 75%
Non-hydro Renewables 3%
Hydroelectric 18%
Argentina Energy Generation Portfolio – Projected 2017
• Overall electricity growth increase lower than neighbors
• Conventional thermo increase • GHG and water
implications are important
• Hydro constant (decreased share of national generation)
Mexico
Nuclear 4%
Conventional Thermo
81%
Non-hydro Renewables
4%
Hydroelectric 11%
Mexico Energy Generation Portfolio
Nuclear 3%
Conventional Thermo
85%
Non-hydro Renewables
3%
Hydroelectric 9%
Mexico Energy Generation Portfolio – Projected 2017
• Highest thermo share of any larger Latin American country • Water impacts (esp.
groundwater) are extreme
• Major renewables potential (solar in Northwest, wind in Tehuantepec Isthmus)
• Ambitious renewables targets, but inadequate investment
Source: Wada et al. 2010. Global depletion of groundwater resources. Geophys. Res. Lett., 37, L20402.
GW (ground-
water) pumping
Climatic variability
Aquifer depletion
Electrical energy supply
Increasing
temps. raise
ET, crop-water
demand
Surface flow
variability shifts
irrigation demand to
GW
Low-cost
electricity
increases GW
pumping
Electricity timing,
reliability reduce
irrigation efficiency
Irrigation ET may
alter energy
balance, sensible
& latent heat flux
GW depletion may
contribute to sea-
level rise & other
global change
GW pumping
shifts to off-peak
supply; may alter
power reliability
Increasing temps.
raise electricity
demand for cooling,
water supply,
irrigation
Power generation
influenced by
hydro-climatic
trends & carbon
mitigation policy Increasing power
demand met by
conventional
generation may
increase
emissions,
negating longer
term mitigation
Increasing power
demand is
required for many
short-term climate
adaptation
measures
GW depletion
may reduce
availability of
thermoelectric
cooling water
Gro
un
dw
ate
r-E
ne
rgy
Nexus
2 1
GW (ground-
water) pumping
Climatic variability
Aquifer depletion
Electrical energy supply
GW
-E N
exu
s O
ver
Tim
e
?
?
?
?
With 2% annual increase in tarifa 09
2% annual increase over 21st Century means tarifa 09 in 2100 would reach current
2010 tariffs for domestic high-consumption or public service users (in constant 2010
pesos). Instead, from 1999-2009, tariffs fell at a compound rate of 0.94% annually.
Without 2% annual increase in tarifa 09
Mex. State Groundwater Titled & Pumped
Pumped = 1.55*Titled
R2 = 0.9421
0.E+00
1.E+09
2.E+09
3.E+09
4.E+09
0.E+00 1.E+09 2.E+09 3.E+09 4.E+09
Vol. Titled (m3/yr)
Vo
l. P
um
pe
d (
m3
/yr)
Chihuahua
Sonora
Guanajuato
Coahuila
Regulation unsuccessful Drilling bans (vedas) and concession titles alone are inadequate; pumped GW exceeds titled GW
Legal and regulatory approaches must focus on the nexus
• Ley de Energía para el Campo (2002) a good
attempt, but strongly opposed
– Límite de energía anual based on concessioned
volume
– This nexus-based regulation was supplanted in
2003 by night-time tarifa 9N (50% day-time rate)
– 2006 farmers secured a Mex$ 0.10 per kWh
subsidy on daytime tariffs (SAGARPA, Mex$ 686
million = US$ 62 million)
Agricultural power sales by CFE
0
1,000,000
2,000,000
3,000,000
4,000,000
5,000,000
6,000,000
7,000,000
8,000,000
9,000,000
10,000,000
0%
2%
4%
6%
8%
10%
12%
14%
19
62
19
64
19
66
19
68
19
70
19
72
19
74
19
76
19
78
19
80
19
82
19
84
19
86
19
88
19
90
19
92
19
94
19
96
19
98
20
00
20
02
20
04
20
06
20
08
(MW
h)
Per
centa
ge
of
tota
l d
eman
d
Year
Electricity demand for agricultural groundwater pumping in Mexico, 1962-2009
Agric. groundwater pumping (night)
Agric. groundwater pumping (regular/ day)
Agric. groundwater % of total demand
High tarifa 09 states are increasing pumping
0
200,000
400,000
600,000
800,000
1,000,000
1,200,000
1,400,000
1,600,000
1,800,000
2,000,000
1988
1990
1992
1994
1996
1998
2000
2002
2004
2006
2008
MW
h
Sonora Power Consumed to Pump Groundwater
Night
Reg./ day
0
200,000
400,000
600,000
800,000
1,000,000
1,200,000
1,400,000
1,600,000
1,800,000
2,000,000
1988
1990
1992
1994
1996
1998
2000
2002
2004
2006
2008
MW
h
Chihuahua Power Consumed to Pump
Groundwater
Night
Reg./ day
0
200,000
400,000
600,000
800,000
1,000,000
1,200,000
1,400,000
1,600,000
1,800,000
2,000,000
1988
1990
1992
1994
1996
1998
2000
2002
2004
2006
2008
MW
h
Coahuila Power Consumed to Pump
Groundwater
Night
Reg./ day
0
200,000
400,000
600,000
800,000
1,000,000
1,200,000
1,400,000
1,600,000
1,800,000
2,000,000
1988
1990
1992
1994
1996
1998
2000
2002
2004
2006
2008
MW
h
Guanajuato Power Consumed to Pump
Groundwater
Night
Reg./ day
GW pumping driven by virtual water (export veg/fruit)
0
200
400
600
800
1,000
1,200
1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009
MC
M/y
ear
Mexico's Virtual Groundwater Exports in Vegetables and Fruits to the U.S.
Other fruit
Citrus
Other vegetables
Peppers
Onions
Tomatoes
0
200
400
600
800
1,000
1,200
1,400
1,600
1,800
2,000
1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009
MC
M/y
ear
Mexico's Total Virtual Water Exports in Vegetables and Fruits to the U.S.
Not groundwater
irrigated
Groundwater
irrigated
Virtual surface water
Virtual groundwater
CONAGUA – National Water Commission
CFE – Federal Electricity Commission
• Contentious rivalry must move to
collaborative relationship
• Need extensive data sharing for informed
decision-making
• Water demand for power generation will
only increase
• Hydropower – another nexus opportunity
lost
GW users self-regulation COTAS
• Groundwater technical committees
• CONAGUA model
– coordination platform centered on federal
authority
• Guanajuato state model
– IWRM but without legal mandate
– Lack incentive mechanisms
Policy choices
• Trend towards renewables: some are quite water intensive (e.g. biomass, concentrating solar thermal), while others are not (PV solar, wind, wave)
• What is the future of hydropower, nuclear, and fossil electricity? (carbon vs. water tradeoffs)
Water-energy-climate futures
• Water, energy, interlinked with climate – the environmental challenges that define our era
• Growing attention paid to water-energy nexus
• Propositions:
– technological obstacles are surmountable
– resource conservation is inevitable, driven by financial limitations and efficiency gains
– institutional arrangements a seemingly intractable constraint to the virtuous water-energy-climate cycle
