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Implications of future energy choices in 

the energy-water-land nexus

WREF Forum: Energy-Water Nexus: An 

International Perspective

Robin L. Newmark

Jordan Macknick, Garvin Heath, Sean Ong, 

Paul Denholm, Robert Margolis, Billy Roberts

May 14, 2012

NREL/PR-6A20-54951
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Energy-Water-Land Nexus

Energy

Water Land

What are the water 

implications of future 

energy systems? 

What are the energy 

requirements for water 

systems?

What will be the impact of 

renewables on our land 

resources?

What role can renewable energy play in our future?

Energy-Water Nexus Food vs. Fuel

Competing uses of water and land
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We analyze different Clean Energy Standards (CES) utilizing the 

Regional Energy Deployment System (ReEDS) model 

134 Power Control Areas

356 Solar and Wind Resource Regions

Constraints:

• Electricity demand 

• Reserve requirements 

• Regional resource supply 

• State and Federal policy 

• Transmission 

Clean Energy Standard (CES)

• 2011 State of the Union Address

• 80% of electricity from clean sources by 2035

• Partial clean energy credit for high efficiency 

natural gas, carbon capture and storage 

technologies

• Cost/performance data utilized:

- AEO 2011 (EIA Annual Energy Outlook)

- B&V 2011 (Black and Veatch 

independent estimates)

- Cooling system policy

Resources/Technologies:

• Conventional (fossil and nuclear)

• Renewables

• Storage

• Demand-side technologies

Biofuels: Billion Ton Study

• 2011 update to 2005 report

• Displace 30% of U.S. petroleum consumption

• Sustainably produce 1 billion dry tons of 

biomass for energy annually

Short, W., Blair, N., Sullivan, P., and T. Mai. ReEDS Model Documentation: Base Case Data and Model Description. 

NREL Report. 2009.

U.S. Department of Energy. 2011. U.S. Billion-Ton Update: Biomass Supply for a Bioenergy and Bioproducts Industry. 

R.D. Perlack and B.J. Stokes (Leads), ORNL/TM-2011/224. Oak Ridge National Laboratory, Oak Ridge, TN. 227p.
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Different cost/performance assumptions create different 

pathways to an 80% Clean Energy Standard by 2036

Source: Steinberg et al., (forthcoming) 
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Different cost/performance assumptions create different 

pathways to an 80% Clean Energy Standard by 2036

Source: Steinberg et al., (forthcoming) 
6

Renewable penetration by 2036

Different cost/performance assumptions create different 

pathways to an 80% Clean Energy Standard by 2036

Source: Steinberg et al., (forthcoming) 
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Energy

Water Lan

What are the Energy-Water implications?
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(insert really cool image/supergraphic from your work)

Caption or heading (if you have one)

Operational water consumption factors for electricity generating technologies 

CSP and PV Biopower Nuclear Natural Gas Coal

Recirculating Cooling Once-through Cooling Pond Cooling Dry Cooling Hybrid 

Cooling

No Cooling 

Required

Source: Macknick et al. 2011

Water impacts for electricity generation technologies range widely Operational water consumption (Gal/MWh)
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CES scenario: National trends in power sector water intensity

BAU 2036 vs 2006

CES AEO 2036 - 2006

CES B&V 2036 - 2006

Climate change may 

enhance impacts 

locally and regionally

Consumption decreases to different extents 

Regional impacts vary

Source: Newmark et al., 2011
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Water use for biofuel production is highly variable 

and depends on crop type and location

Some crops require more water, regardless 

of location

Irrigation requirements vary spatially

Irrigated energy crops could result in local 

or regional competition for water

 Water Footprint for Switchgrass

 Water Footprint for Corn

Source: Inman et al., (forthcoming); 

Source: Gerbens-Leenes et al., 2009
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Energy

Water Land

What are the Energy-Land implications?
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NEW YORK TIMES

June 7, 2011 Meeting California’s RPS would require:

“5 Manhattans” for Solar

“70 Manhattans” for Wind

What is the land footprint of renewables? 

It depends on your definition

Primary accounting methods

 Direct Impact

 Total Plant Area Impact

From Denholm et al., 2009
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Land footprint estimates for renewable technologies differ 

widely based on the metric used

(Acres/MW) Geothermal1 Biopower2 Utility PV3 CSP4 Wind5

Direct 

Impact 0.6 900 9 7 0.7

Total Area 14 900 9 7 86

900

1. Pimentel, 2002; Geothermal PEIS Ch. 4, 2008. Assumes 85% capacity factor, per ReEDS model assumptions

2. IEA, 2007

3. Solar PEIS Appendix M, 2010

4. Solar PEIS Appendix M, 2010. Averages land impacts from power tower (9 acres/MW) and parabolic trough (5 acres/MW)

5. Denholm et al., 2009

Wind and geothermal land 

footprints vary by 1-2 orders 

of magnitude

Land footprints for solar PV, 

CSP, and biopower are similar 

under both definitions
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What is the effective footprint? 

Co-location of agriculture with wind and solar plants can reduce the 

overall land footprint for renewable energy technologies

Sunflowers for oil production grown under panels 

in Wisconsin. Courtesy: Milwaukee Journal Sentinel, 2011

Cows and pasture beneath panels in 

Massachusetts. Courtesy: M. Lehan, 2011

Tapping solar resources in non-irrigated 

corners of center pivot irrigation fields.

Source: Roberts, B. NREL Technical Report.

TP-6A20-51330, 2011

Wind farm co-located with an agriculture farm. Wind farm co-located with a cattle operation.

Co-location can reduce 

the land footprint of 

renewables and reduce 

food vs. fuel conflicts 
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AEO-CES

BAU

B&V-CES

Land use for renewables makes up a small fraction of total 

state land area

Direct Impact Method Example: Biopower and wind Direct Impact Method

% land-use

 % land-use

% land-use

% land-use

% land-use

% land-use

Biopower Source: Newmark et al., 2011 Wind
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AEO-CES

BAU

B&V-CES

Land use for renewables makes up a small fraction of total 

state land area

Total Area Method Example: Biopower and wind Total Area Method

% land-use

 % land-use

% land-use

% land-use

% land-use

% land-use

Biopower Source: Newmark et al., 2011 Wind
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Land for biofuels may compete with land for biopower

electricity and other agricultural uses

Business as usual

B&V-CES

% land-use

% land-use

AEO-CES

% land-use

Source: Newmark et al., 2011

Source: Pienkos, 2007

Source: DOE, 2011 

Source: 

Biopower Pienkos, 2007
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Summary

Energy

Water Land

Future energy choices can have implications in the energy-water-land nexus.

Renewables can help achieve energy policy goals

Integrated planning is needed to support sustainable energy, water and food goals

and help prevent unsustainable demands on land and water resources 

Renewables have the potential 

to reduce the water intensity of 

our electricity sector

Renewable energy impacts on 

water withdrawals and 

consumption will vary 

geographically

The land footprint of 

renewables varies greatly 

depending on metrics used

Co-location of renewables with 

agriculture can mitigate fuel vs. 

food conflicts