CONVENTIONAL AND DECENTRALIZED WATER SUPPLY INFRASTRCUTURE:

CONVENTIONAL AND DECENTRALIZED WATER SUPPLY INFRASTRCUTURE:

ENERGY CONSUMPTION AND CARBON FOOTPRINTENERGY CONSUMPTION AND CARBON FOOTPRINT

Tamim YounosResearch ProfessorResearch Professor

Department of Geography & Water Resources Research Center Virginia Tech

AWRA 2009 Spring Specialty ConferenceManaging Water Resources and Development in a Changing Climate

Anchorage, Alaska

May 4 - 6, 2009

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Carbon Footprint of Water ConsumptionConsumption

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Total Energy Use in the U.S. (2005)Total Energy Use in the U.S. (2005)

100 quadrillion BTU or 29,000 TWh(T = trillion)

3 – 4 % of total energy use is attributed gyto water/wastewater treatment and distribution/discharge

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Energy Use in Conventional Water Supply InfrastructureWater Supply Infrastructure

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Water Supply Infrastructure: Water Supply Infrastructure: Water Treatment and DistributionWater Treatment and Distribution

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Drinking WaterWashing & g

CookingFlushing Toilets

Landscape IrrigationCar Wash

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Blacksburg and VT

Sanitation Authority

Water Authority

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Carbon Footprint for Blacksburg Water SystemCarbon Footprint for Blacksburg Water System

• Total Water Delivery: 3.0 MGD

• Electricity Use: 1.67 kWh/1,000gal delivered(Literature 0.25 – 3.5 kWh/1,000 gallons, AWWARF 2007)

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70% of use energy goes to distribution

30% of energy use goes to water treatment

Virginia Tech Study 2007

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Estimating Carbon FootprintEstimating Carbon Footprint

Carbon Dioxide Emissions from Electric Power Generation (Kloss 2008) Fuel Type Carbon Dioxide Output Rate CO2 Output per MG

Pounds CO2/kWh WaterDelivered (x 1.450 kWh)

Coal 2.117 3,070 lbs Petroleum 1.915 2,775 lbs Natural gas 1 314 1 905 lbsNatural gas 1.314 1,905 lbs

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Carbon Footprint for Blacksburg Water SystemCarbon Footprint for Blacksburg Water System

• Electricity Use: 1.67 kWh/1,000gal delivered

• Total water delivery: 3.0 MGD

• Carbon Footprint for Blacksburg Water System3 0 MGD x 1 67 kWh/1 000 gal x 2 1173.0 MGD x 1.67 kWh/1,000 gal x 2.117 lb/kWh = 10606.17 lb CO2/day (or 4,811 Kg/day) or 1,756 metric ton/year.

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Building Carbon Footprint Due to Water ConsumptionBuilding Carbon Footprint Due to Water ConsumptionBuilding Carbon Footprint Due to Water ConsumptionBuilding Carbon Footprint Due to Water Consumption

Building Name and Location

Annual water consumption - water delivered via

conventional system - (Gallons/Year)

Estimated electricity use attributed to water use

(kWh)

Estimated CO2 output lb/Year (kg/year)

(Gallons/Year) (x 1.67 kWh/1,000 gallons) (x 2.117 CO2/kWh)

Blacksburg Motor Company, Blacksburg

51,000

85.17 180.30 (81.6)

The YMCA Center, Blacksburg

121,500

202.9 429.5 (194.84)

Whittemore Hall VT 1 420 700 2372 6 5022 8Whittemore Hall, VT 1,420,700

2372.6 5022.8(2,278.0)

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Shortcomings of Conventional Water InfrastructureShortcomings of Conventional Water Infrastructure

• High infrastructure cost

• High water loss (25 to 30%) – leaks through distribution system

Energy intensive pumping & water purification• Energy intensive – pumping & water purification

• Pipes susceptible to contaminant intrusion & bacterial growth

• The system dependency on imported water source

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The Vision for a Pipe-less Societyp y

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Decentralized Water InfrastructureDecentralized Water Infrastructure

ConceptReplace large infrastructure with smallerlocalized systemsy

Goals: Water and energy conservationGoals: Water and energy conservationWatershed protection

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Decentralized Water InfrastructureDecentralized Water Infrastructure

O it W t t T t t• Onsite Wastewater Treatment

• Low Impact Stormwater Management Systems

• Rainwater Harvesting Systems

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g y

Rainwater HarvestingRainwater Harvestinggg

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Modern Rainwater Harvesting Systems Modern Rainwater Harvesting Systems

• Rooftop Rainwater Collection

• Rainwater Use

RECHARGECOOLINGCAR WASHING

FOUNTAINSIRRIGATION

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http://www.rainwatermanagement.com

Rooftop Rainwater HarvestingRooftop Rainwater HarvestingRooftop Rainwater HarvestingRooftop Rainwater Harvesting

Indoor Use (gal/Year)

Outdoor Use (landscape Irrigation) (gal/year)

Total Use (gal/year)

Available Rain Water (gal/year)

Excess Water (gal/year)

(+ or - ) (gal/year) (+ or )

BMC 30,000 (25 users)

21,000 (1,000 Sq.ft)

51,000 209,943 + 158,943

BMB 106,000 147,000 252,984 198,754 - 54,230 (80 users) (7,000 Sq-ft)

URV (gallons/month) = Roof-Area (sq-ft) x Average Rainfall (inch/month) x C x 0.6233

1 000 sq ft roof will collect 620 gallons per 1 inch of rainfall

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1,000 sq.ft. roof will collect 620 gallons per 1 inch of rainfall

Change in Building Footprint Due to Rainwater Harvesting

Change in Building Footprint Due to Rainwater HarvestingHarvestingHarvesting

Building Name and Location

Rainwater harvesting/ use potential (Eq. 1)

(gallons/year)

Difference between harvested rainwater

and water consumption

Estimated electricity use (kWh) for delivery

(x 1.67 kWh/1,000 ll )

Estimated CO2 output

lb/year (kg/year) ( 2 11 CO2/k h)(gallons/year) consumption

(gallons/year) gallons) (x 2.117 CO2/kWh)

Blacksburg Motor Company, Blacksburg 209,943 51,000 < 209,943

(0) 0 0

The YMCA Center, Blacksburg 708,373 121,500 <708,373

(0) 0 0

Whitt H ll VT 500 000 920 700 1537 6 3255 (1476 5)Whittemore Hall, VT 500,000 920,700 1537.6 3255 (1476.5)

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Futuristic ApplicationsFuturistic Applications.

Harvested rainwater

Green Buildings

Generated renewable energy converted to electricity

Added pressure

Pump

• Save potable water• Save energy

Red ce carbon

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• Reduce carbonfootprint

AcknowledgmentsAcknowledgmentsAcknowledgments

Co authors: Funding:

Acknowledgments

Co authors: Funding:Co-authors: Funding:

Caitlin Grady ICTAS -Virginia Tech

Co-authors: Funding:

Caitlin Grady ICTAS -Virginia TechCaitlin Grady ICTAS Virginia TechTeresa Chen NSF - REUTammy Parece VWRRC – Virginia Tech

Caitlin Grady ICTAS Virginia TechTeresa Chen NSF - REUTammy Parece VWRRC – Virginia Tech

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