The Water-Energy Nexus: Technology and Policy

4th IWA Annual Meeting on Urban WaterNovember 25-27, 2018

Harbin, P.R. China

Osvaldo A. Broesicke, Junchen Yan, &

John C. Crittenden, Ph.D., P.E., N.A.E. (US & China)

Director of the Brook Byers Institute of Sustainable Systems

Georgia Research Alliance Eminent Scholar of Sustainable Systems

Hightower Chair of Civil and Environmental Engineering

Brook Byers Institute for Sustainable Systems, Georgia Institute of Technology, Atlanta, GA

E-Mail: john.crittenden@ce.gatech.edu 1

OUTLINE

• Water-Energy Nexus• Water for energy

• Centralized and Decentralized Water and Energy Systems

• Water Systems• Low Impact Development

• Greywater Reclamation

• Policy Tools and Modeling

• Atlanta Projections for Distributed Energy

2

‘Water for Energy’ and ‘Energy for Water’ in USWater for Energy

• Thermoelectric power generation

accounts for ~ 52% of fresh surface

water withdrawals.

• The average (weighted)

evaporative consumption of water

for power generation over all

sectors is around 2.0 Gal/kWh.

Energy for Water

• About 4% of the total electricity

consumption in the US is for the

water and wastewater sector1

• Of the total energy required for

water treatment, 80% is required

for conveyance and distribution

Energy

Source

Gal/kWh

(Evaporative loss)

Hydro 18.27

Nuclear 0.62

Coal 0.49

Oil 0.43

PV Solar 0.030

Wind 0.001

Water Treatment* kWh/MGal

Surface Water Treatment 220

Groundwater Treatment 620

Brackish Groundwater

Treatment3,900-9,700

Seawater Desalination 9,700-16,500

Source: U.S. DOE (2014)3

Water for Primary Energy in US

Water for Fuel Extraction and Processing

3

4

9

9.5

73

76

30

43

50

1010

90

1 10 100 1000 10000

Natural gas + transportation

Coal ming + washing

Coal + slurry pipeline

Uranium mining + enrichment

Oil (primary - seconday)

Oil (enhanced oil recovery)

Oil sands

Natural gas + gas to liquid

Coal + coal to liquid

Corn ethanol

Cellulosic ethanol

Water Consumption

(Gallons/MMBtu)4

Source: U.S. DOE (2014)

Water as a Heat Source: False Creek Neighborhood

Energy Utility Vancouver, BCSewage heat recovery supplies

70% of annual energy demand

and reduces GHG emission by

50%

5Source: City of Vancouver (2018)

Low Impact Development

Principles of Low Impact Development (LID):

• Onsite management vs. end-of-pipe

• Infiltration vs. runoff

• Integrated systems vs. separate systems

6

Benefits:

• Reduced stormwater runoff

• Reduced erosion

• Reduced pollution (water

and air)

• Reduced heat island

• Increased recreation

System-based Benefits of LID Best Management Practices

Water Resources Wastewater/Stormwater

• Rainwater• Surface water• Groundwater• Reclaimed water

• Storm sewers• Combined sewers• Wastewater systems

Low Impact Development

Water & Wastewater• Rainwater• Surface water• Groundwater• Reclaimed water

Social Benefits• Rainwater• Surface water• Groundwater• Reclaimed water

Transportation Infrastructure

• Pedestrian walkways

• Cycling

Food Infrastructure

• Urban agriculture

Energy Infrastructure

• Reduced heat island

Water Retained/Slowed by Green Infrastructure

Can Enhance Other Infrastructures

More Concentrated Wastewater

Enables:• Energy Efficiency and

Recovery (reduces energy demand)

• Nutrient Recovery (can be utilized for green infrastructure projects

Reduced/Delayed Flow

7

80% penetration of autonomous vehicles

28% of the cars we have today At least 72%

reduction in parking space (up to 90%)

24.7% reduction of impervious area and

stormwater runoff

Additional 17% of city land for green space and stormwater management

The Connection between Autonomous Vehicles, Green Space and Water

8Source: Zhang et al (2015)

9

Normalization and Weighting

Damage to: Hierarchist (H) Egalitarian (E) Individualist (I)

Human Health 40% 30% 55%

Ecosystem 40% 50% 25%

Resources 20% 20% 20%

Normalization: The damage categories (and not the impact categories) are

normalized on an European level (damage caused by 1 European per year),

mostly using 1993 as base year, with some updates for the most important emissions.

Please note that the normalization set is dependent on the perspective chosen.

Weighting Perspectives:

10

11

Water SystemsLID, Rainwater Harvesting, and Xeriscaping

Greywater Reclamation

Decentralized technologies

can displace or

supplement conventional

centralized systems

Majority of water demands come

from irrigation – LID and Xeriscaping

heavily reduce demands.

• Rainwater harvesting cannot meet

demands of higher pop. Densities

• Smaller green space per capita

ratio

Most demands are domestic (e.g.,

faucet, laundry, or toilets)

Sources: Jeong et al. 2016 and Jeong et al. 2018

Water flows with LID & Reclamation, Ex.

Rainwater

Harvesting

Water

Treatment

Plants

Xeriscape Irrigation, 3

Toilet, 25

Laundry, 19

Shower, 16

Faucet, 15

Bath, 2

Dishwasher, 1

Laundry, 1Wastewater

Treatment

Plants

47

35

79

Evapotranspiration

Same Size Waste Water Treatment Plant

Water

Treatment

Plants

Outdoor Irrigation, 11

Toilet, 25

Laundry, 18

Shower, 16

Faucet, 15

Bath, 2Dishwasher,

1

Laundry, 2

Wastewater

Treatment

Plants

Evapotranspiration

Greywater Reclamation

25

11

36

54

~54

Residuals

Smaller Flow, More Concentrated; Smaller Plant: Better energy and nutrient recovery.

Drinking Water

Rainwater

Reclaimed Water

Greywater

A 2-story apartment unit of Atlanta, GA (gal/cap-day)

Sources: Jeong et al. 2016 and Jeong et al. 201812

Treating 47 gal/cap-day of

rainwater to potable standards

could make apartment “off-grid”

for supply

Black Water

Interdependency between Water Infrastructure and Socio-Economic Environment

Source: Philadelphia Water Department (2009)

Philadelphia case

– LID (low impact development) options instead

of storage tunnel for CSO (combined sewer

overflow) control in watershed areas;

– Total net benefit over the 40-year projection :

2 billion (LID for 25 % runoff), 4.5 billion (LID

for 100 % runoff), 2009 USD.

13

14

Agent-Based Modeling: Simulating the Adoption Rate for More Sustainable Urban Development

Principal Agents: Prospective Homebuyer,

Homeowners, Developers, Government

Policy Tool Impact fee for LID non-

compliance penalty:

• $13,000 per unit for single-family house

• $1,500 per unit for apartment home

Policy Implementation Effect After 30 years:

• 40% reduction in potable water demand from

centralized plant in MSD as compared to BAU

• 36% increase in net property tax revenue

generation in MSD as compared to BAU

65%

35%

0%

20%

40%

60%

80%

100%Business As Usual (BAU)

41%

59%

0%

20%

40%

60%

80%

100%

0 5 10 15 20 25 30Year

More Sustainable Development

(MSD)

Percent of households compared to total households after 30 years

Percent of single-family households compared to total households after 30 years

Percent of multi-family households compared to total households after 30 years

Lu et. al (2016)

Combined Heat and Power

Useful Electricity

(35 units)

Useful Heat

(50 units)

Total Loss

(15 units)

Input Energy

(100 units)

Separate Electric Power

Useful Electricity

(29 units)

Input Energy

(100 units)

Generation Loss

(65 units)Grid Loss

(6 units)

Breaking the Energy Water Nexus: Recapturing Lost Heat in Combined Heat & Power System; Air Cooled (No water needed)

Air-cooled

Microturbine

Absorption

Chiller

Electricity

Heating

Cooling

15

Decentralized Energy Production at Perkins

+ Will, Atlanta Office (45000 sq. ft.)• Air Cooled Microturbines are used for heating and cooling using

Absorption Chillers and supply 40% of the total electricity.

Adsorption Chiller 65 kW Microturbine Perkins+Will Office Building

Water Reduction: >50%

CO2 Reduction: 15 - 40%

NOX Reduction: ~40%

Adding Distributed Generation as part of the Grid:

Possible Future: Carbon Neutral Natural Gas Grid!!!

16

SPATIAL DATABASES FOR URBAN MODELING - 1

The SMARTRAQ project

Supports research on land

use impact on transportation

and air quality

1.3 million parcels in the 13

metropolitan Atlanta non-

attainment counties

17

RESIN Meeting Sept. 24, 2009

SMARTRAQ DATA AND ATTRIBUTES

Address

Road Type

City

Zip Code

Owner Occupied

Commercial/Residential

Zoning

Sale Price

Sale Date

Tax Value

Assessed Value

Improvement Value

Land Value

Year Built

No. of Stories

Bedrooms

Parking

Acreage

Land Use Type

Number of Units

X,Y Coordinate

Estimated Sq Feet

Total Sq Feet

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Growth Scenarios in Atlanta

James et al (2018)

Single-family Res Multifamily Res Pub. Institutional

Commercial Office Commercial W.S. Industrial

Agriculture Parks

Conservation Forest

Other Developable Open Water

Business As Usual2030

More Compact Growth2030

Base Year 2005

19

Potential GHG and Cost Reductions in 2030By 2030, implementation of CCHP in all new and existing residential and commercial buildings could: reduce CO2 emissions by ~16 Mt, NOXemissions by ~24 kt, decrease water-for-energy consumption by 315 MGD and decrease energy cost by $740 million per year for the Metro Atlanta region with More Compact Growth

CO2 (106 tonnes) NOX (103 tonnes) Water Consumption (mgd)

0

5

10

15

20

25

30

No CCHP CCHP CCHPw/ netmet

2005 level

-90%-63%

0

5

10

15

20

25

30

35

NoCCHP

CCHP CCHPw/

netmet

2005 level

-50%

-8%

0

50

100

150

200

250

300

350

400

No CCHP CCHP CCHP w/netmet

2005 level

-74% -93%

James et al (2018)20

Atlanta Water Demand for New Residential and Commercial Buildings

Municipal Water Demand Water for Energy

2,208

361

141

729

707

707

0

500

1,000

1,500

2,000

2,500

3,000

3,500

Grid CCHP CCHP w/netmet

With

dra

wa

ls (

10

6g

al p

er

da

y)

64% 71% 221

36

14

108

108

108

0

50

100

150

200

250

300

350

Grid CCHP CCHP w/netmet

Co

nsu

mp

tio

n (

10

6g

al p

er

da

y)

56% 63%

Installation of Air Cooled Microturbines saves 2.7 times the amount of water used for domestic consumption

21

James et al (2018)

Based on Atlanta’s Grid Mix (~ 2 gal/kWh based on consumption from McDonough)

251

33

10

30

4

1

32

12

27

4

21

10

100

1000

NoCCHP CCHP CCHP w/netmet

NoCCHP CCHP CCHP w/netmet

Grid Mix CCNG

Wa

ter

for

En

erg

y C

on

su

mp

tio

n-g

rid

m

ix (

MG

D)

Atlanta Water-for-energy Demand for New Residential and Commercial Buildings – CCHP and Combined Cycle Natural Gas

22

87% 95% 89%

86% 95%

James et al (2018)

Business As Usual (BAU)

More Compact Growth (MCG)

• Water-for-Energy is impacted much more than domestic water demands

• Not a major difference between BAU and MCG

221

NO CCHP CCHP CCHP With

Net Metering

BAU MCG BAU MCG MCGBAU

0.5%

1%

1.5%

2%

0

LC

As

ing

les

co

re:

%a

ve

rag

eim

pa

ct

of

Eu

rop

ea

n

3.9%

1.5%

5.4%

27%40.5%

2.5%

Functional Unit:• Projected Annual Energy

Consumption by eachAtlanta citizen under BAU orMCG scenarios

LCIA Single Score under BAU and MCG scenarios

ReCiPe2016 endpoints Method• single score refers to % of annual European average environmental damage per capita

Suite of Energy Technologies

24

Dis

trib

ute

d E

ne

rgy S

up

ply

Sys

tem

Air-cooled

Microturbine

Absorption

Chiller

Alternative 2:

Photovoltaics

and/or Wind

Alternative 1:

Thermal Storage

Alternative 3:

Electric Vehicle

Alternative 4:

Electric Storage

Co

nve

nti

on

al

Sys

tem

s

Furnace or

Boiler

Refrigerated Air Power Grid

En

erg

y In

pu

ts

Photovoltaics and wind turbines are intermittent, and must be paired

with another technology to be reliable.

The large variation in PV output demands a higher

capacity of spinning reserves

Solar PV Simulation Results in Hourly Resolution for Atlanta, GA

25

Test Beds

26

The Springs community (81 homes), located in Chandler, AZ, was first selected and used as a test bed to research microgrid design methods.

MICROGRID: PV System (160 kW) and Gas Turbine (270 kW) Supplying Feeder

27

One Size Does Not Fit All

28

Building energy demands (power, heating, and cooling) vary based on climate and function.

Energy

StorageRenewables

Co- and tri-

generation

Vehicle-to-

Grid

Source: Broesicke et al. (unpublished)

Final Thoughts: Energy and water systems are heavily interconnected and their resilience and sustainability can be enhanced using decentralized systems that are coupled to centralized systems.

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Source: Broesicke et al. (unpublished)

Manufacturing 4.0: What We Know

is Worth More What We Make and it is a Great

Opportunity for Sustainable Engineering

Revenue

What We Know

Material GenomeCyber-physical Infrastructures

Target Market and Business Plan

DatafacturingSustainable Engineering

Toolbox

What We Make: Metal Bashers

Have Smaller Revenue

:

Businesses that use Market Data,

Supply Chain Data, Performance

Data and Informed Design Will

Receive the Most Revenue and

They Get to Choose Which OEM

Makes Their Widgets.

Examples: Apple OS

Google OS Android

Future: Tech Giant Rule??

Examples: FoxCon,

Samsung

Future Metal Bashers

McKensey Manufacuring 4.0: Four new types of business models

As-a-service business models– Pay-by-usage – pay only for allotted time or

materials

– Subscription-based – provides agreed-upon services based on a subscription

Platforms – products, services, & information can be exchanged via predefined communication streams

1. Interaction platform – provides a marketplace

2. Technology platform/ecosystem – companies facilitate further development of advanced products and apps based on their own tech & products

Intellectual Property Rights (IPR) based models– Recurring business based on subscription of

software, maintenance, & support• Further monetized by adding training courses

Data-driven business models1. Direct monetization of data

• Collect data via the primary product• Crowdsourcing

2. Indirect monetization of data• Use of insights to identify & target specific

customer needs & characteristics

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*These new business models are leading the shift away from physical

product revenues towards more service-based revenues, platforms, &

developer ecosystems

Low Impact

Development

Rainwater

Harvesting

Greywater

Reclamation

Energy

StorageRenewables

Co- and tri-

generation

Vehicle-to-

Grid

Autonomous

Vehicles

Mixed Land

Use

Transit-

Oriented

Walkable

Community

More than 50 Technologies Gigatech Platform: Multidisciplinary

Design Optimization

Demand

Simulation

Water

Management

Simulation

Energy Supply

Simulation

Analysis and

Optimization

Potential Synergistic

Effects

1 2

3

• Improve air quality and health• Livable environment• Reduced water and energy consumption• Lower dependence on centralized systems • Larger share of renewables in the

electricity mix • Reduced vehicle-miles travelled • An increase in tax revenue• Enhanced system resilience

Synergies of Infrastructure Symbiosis

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References1. U.S Department of Energy. The Water-Energy Nexus: Challenges and Opportunities. (2014). doi:10.1007/s13398-

014-0173-7.2

2. City of Vancouver. How the utility works. Home, property, and development (2018). Available at: https://vancouver.ca/home-property-development/how-the-utility-works.aspx. (Accessed: 11th January 2018)

3. Zhang, W., Guhathakurta, S., Fang, J. & Zhang, G. Exploring the impact of shared autonomous vehicles on urban parking demand: An agent-based simulation approach. Sustain. Cities Soc. 19, 34–45 (2015).

4. Garrison, N., Wilkinson, R. & Horner, R. A Clear Blue Future: How Greening California Cities Can Address Water Resources and Climate Challenges in the 21st Century. Natl. Resour. Def. Counc. (2009).

5. Jeong, H., Broesicke, O. A., Drew, B., Li, D. & Crittenden, J. C. Life cycle assessment of low impact development technologies combined with conventional centralized water systems for the City of Atlanta, Georgia. Front. Environ. Sci. Eng. 10, 1 (2016).

6. Jeong, H., Broesicke, O. A., Drew, B. & Crittenden, J. C. Life cycle assessment of small-scale greywater reclamation systems combined with conventional centralized water systems for the City of Atlanta, Georgia. J. Clean. Prod. 174,333–342 (2018).

7. Philadelphia Water Department (2009) Philadelphia combined sewer overflow long term control plant update, supplemental document volume 2; Triple bottom line analysis

8. Lu, Z., Noonan, D., Crittenden, J. C., Jeong, H. & Wang, D. Use of impact fees to incentivize low-impact development and promote compact growth. Environ. Sci. Technol. 47, 10744–10752 (2013).

9. James, J.-A., Thomas, V. M., Pandit, A., Li, D. & Crittenden, J. C. Water, Air Emissions, and Cost Impacts of Air-Cooled Microturbines for Combined Cooling, Heating, and Power Systems: A Case Study in the Atlanta Region. Engineering2, 470–480 (2016).

10. James, J.-A., Sung, S., Jeong, H., Broesicke, O. A., French, S. P., Li, D. & Crittenden, J. C. Impacts of Combined Cooling, Heating and Power Systems, and Rainwater Harvesting on Water Demand, Carbon Dioxide, and NO x Emissions for Atlanta. Environ. Sci. Technol. 52, 3–10 (2018).

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