Urban Water Security Research Alliance Life Cycle Assessment - - PowerPoint PPT Presentation

Life Cycle Assessment Perspectives for Total Water Cycle Planning Joe Lane

Total Water Cycle Management Planning

Science Forum, 19-20 June 2012

Urban Water Security Research Alliance

Research Outcomes

Research goal How can LCA inform the TWCM process…? Findings

• poor externalities accounting will lead to unintended consequences
• poor system boundary definition will lead to unintended

consequences and/or missed opportunities

• LCA environmental breadth provides future insight
• implementation is practical
• interpretation is challenging
• certain improvements would greatly increase the

relevance/benefits

TWCP – Caboolture scenarios

Existing Caboolture urban area

• 61% population growth (43,000p)
• nutrient and water supply constraints

Analysis = applied to new population

catchment stormwater water supply wastewater

1

min required

• TSS, TP, TN

reduced by 80/60/45% raintanks (T,L,E) STP growth

2

next best reveg farming BMP ∆TSS, TP, TN 80/60/45% raintanks (T,L,E) STP growth WW  agriculture

3

more ambitious reveg farming BMP enhanced WSUD raintanks (L) STP growth stormwater harvesting and reuse WW reuse  urban areas

Detailed System Boundary & Data

system boundary

• construct + operations
• manufacture and supply of

materials, chemicals, power

• water use = excluded

catchment mgmt / WSUD

• N/P balances from TWCMP

end use profile

• Smart Water research

rainwater tanks and dams

• latest Aus research

treatment plants (WTP, STP, AWTP, SWH, Desal)

• detailed data from GCW + Sth

Cab; SWH reuse = gap

• fugitive emissions science; micropollutant data
• ther aspects
• insight from GCW study + more recent data

potable water savings TN reduction to Cab Rv Greenhouse gas emissions (ML/y) (t N/y) (kt CO2e/y) ‘typical’ pow er use data pow er models developed for this study scope 1,3 excluded fugitive GHG emissions (scope 1); supply of chemicals & construction materials (scope 3) mains excluded mains excluded avg' grid supply desal supply Scenario 1 746 2 2 Scenario 2 746 12 4 Scenario 3 2,764 13 4 potable water savings TN reduction to Cab Rv Greenhouse gas emissions (ML/y) (t N/y) (kt CO2e/y) ‘typical’ pow er use data pow er models developed for this study scope 1,3 excluded fugitive GHG emissions (scope 1); supply of chemicals & construction materials (scope 3) mains excluded mains excluded avg' grid supply desal supply Scenario 1 746 2 2 2 (+9%) Scenario 2 746 12 4 5 (+42%) Scenario 3 2,764 13 4 7 (+80%) potable water savings TN reduction to Cab Rv Greenhouse gas emissions (ML/y) (t N/y) (kt CO2e/y) ‘typical’ pow er use data pow er models developed for this study scope 1,3 excluded fugitive GHG emissions (scope 1); supply of chemicals & construction materials (scope 3) mains excluded mains excluded avg' grid supply desal supply Scenario 1 746 2 2 (1) 2 (1) 7 (1) Scenario 2 746 12 4 (3) 5 (2) 11 (3) Scenario 3 2,764 13 4 (2) 7 (3) 9 (2) potable water savings TN reduction to Cab Rv Greenhouse gas emissions (ML/y) (t N/y) (kt CO2e/y) ‘typical’ pow er use data pow er models developed for this study scope 1,3 excluded fugitive GHG emissions (scope 1); supply of chemicals & construction materials (scope 3) mains excluded mains excluded avg' grid supply desal supply Scenario 1 746 2 2 (1) 2 (1) 7 (1) 15 (2) Scenario 2 746 12 4 (3) 5 (2) 11 (3) 18 (3) Scenario 3 2,764 13 4 (2) 7 (3) 9 (2) 13 (1)

Improvements Affect the Tradeoffs Analysis

• improved data makes a difference
• mains supply matters
• predicting the marginal grid source is problematic

Broader Enviro Scope Identifies Key Issues

‐100% ‐75% ‐50% ‐25% 0% 25% 50% 75% 100%

Freshwater Extraction Eutrophic'n Potential Marine Ecotox Terrestrial Ecotox Global Warming Ozone Depletion Fossil Fuel Depletion Minerals Depletion Photochem

• xidants

Particulates formation

Scenario 1 Scenario 2 Scenario 3

Freshwater Extraction Eutrophic'n Potential Marine Ecotox Terrestrial Ecotox Global Warming Ozone Depletion Fossil Fuel Depletion Minerals Depletion Photochem

• xidants

Particulates formation

WW discharge

0% ‐77% ‐105% ‐122% 0% 0% 0% 0% 0% 0%

irrigation

‐100% ‐1% 0% 173% ‐1% 0% ‐1% ‐3% 0% 0%

fugitive gases

0% ‐27% 0% 0% 0% ‐16% 0% 0% 0% ‐2%

energy

0% 3% ‐4% 6% 74% 101% 74% 28% 23% 54%

chemicals

0% 1% 8% 36% 23% 14% 21% 57% 10% 45%

construct'n

0% 0% 0% 7% 4% 1% 6% 18% 67% 3% Contribution to the change between Scenario 1 & Scenario 2

indirect sources direct sources

50 100

Freshwater Extraction Eutrophic'n Potential Marine Ecotox Terrestrial Ecotox Global Warming Ozone Depletion Fossil Fuel Depletion Minerals Depletion Particulates formation

% contributionto total impact category result mains water supply sewerage + WWT rainwater tanks stormwater

Major WWT Contribution to Enviro Burden

biosolids to disposal biosolids to farms System boundary = all mains supply; all wastewater discharge; all stormwater discharge

‐75 75 150

Freshwater Extraction Eutrophic'n Potential Marine Ecotox Terrestrial Ecotox Global Warming Ozone Depletion Fossil Fuel Depletion Minerals Depletion Particulates formation

% contributionto total impact category result

‐0.02% ‐0.02% ‐0.01% ‐0.01% 0.00% 0.01%

Freshwater Extraction Eutrophic'n Potential Marine Ecotox Terrestrial Ecotox Global Warming Ozone Depletion Fossil Fuel Depletion Minerals Depletion Particulates formation

% change to Australian economy

Scenario 1 Scenario 2 Scenario 3

Different Benchmarks give Different Perspectives

‐10% 0% 10% 20% 30%

Freshwater Extraction Eutrophic'n Potential Marine Ecotox Terrestrial Ecotox Global Warming Ozone Depletion Fossil Fuel Depletion Minerals Depletion Particulates formation

% change to MBRC urban water system

Scenario 1 Scenario 2 Scenario 3

Conclusions

Offsets matter

• avoiding mains water use  net environmental benefit
• water and nutrient offsets (e.g. WW reuse) even better

GHG accounting needs improvement

• 

GHG intensity… if analysis limited to scope 2 (energy) or $/CO2

Life cycle thinking helps

• should explore sensitivity to system boundary selection
• broad environmental scope provides insight to future challenges
• improved impact models would greatly increase their relevance

Benchmarking is useful but needs improvement

• improvements are ongoing; are there other meaningful approaches…?

LCA suited to more focussed comparison of specific options

• rigour highlights key gaps in data/understanding
• quantifying tradeoffs provides transparency

Urban Water Security Research Alliance THANK YOU

Particularly:

• Co-author –

Paul Lant (UQ)

• Andrew Sloane, Phil Wetherell, Niloshree

Mukherjee, Lavanya Susarla (MBRC/UW)

• Kelly O’Halloran (GCW)
• Cara Beal, Rodney Stewart (Smart Water Research Centre)
• Murray, Luis, Esther, Grace, Meng, Ashok and Shiroma (CSIRO)
• Julien Reungoat and many at AWMC
• Nicole Ramilo

and Tony Weber (BMT-WBM)

• David de Haas (GHD)

www.urbanwateralliance.org.au