Rainwater & Greywater Feasibility Dr Lee Bint BRANZ Sustainable Building Scientist

Transcription

1 Rainwater & Greywater Feasibility Dr Lee Bint BRANZ Sustainable Building Scientist

2 Today s Workshop: Background what is this project about? Research Streams who cares? Commercial Building Water Use how much should we be using? Rainwater & Greywater how is it done and what are the options? System Feasibility how are these systems performing? What is Feasibility how can we measure and portray this accurately? Next Steps what can you expect?

3 Background: Doctoral Studies: Understand Water Use Increase Awareness Implementation Outputs: PhD Thesis (VUW) Calculator Tool (WERT) Bright Ideas Challenge Field Study: 36 AKL Office Buildings 57 WLG Office Buildings 2009 to 2011

4 Metric Development: Net Lettable Area (m 2 )

5 Assumed Water Benchmark Outcome: International Research Climate Influences: Heat Rejection Evaporation Irrigation Auckland > Wellington

6 Water Benchmarking Results: Outliers Median 1.03 Median 0.76 Wellington Auckland

7 Tariff Differences: 2011 Auckland Tariff Charge 2011 Wellington Tariff $43 / year Annual Service Fee $100 / year $1.300 / kl Ingoing Water $1.715 / kl $4.056 / kl 75% of Ingoing Water Quantity Outgoing Wastewater % Capital Value Example Office Building: Auckland & Wellington -- $59,000,000 Capital Value 28,000 kl/year Total cost / year Charge Total cost / year $43 Annual Service Fee $100 $36,400 Ingoing Water $48,020 $85,176 Outgoing Wastewater $76,801 $121,620 $124,921

8 Tariff Differences: 2011 Auckland Tariff Charge 2011 Wellington Tariff $43 / year Annual Service Fee $100 / year $1.300 / kl Ingoing Water $1.715 / kl $4.056 / kl 75% of Ingoing Water Quantity Outgoing Wastewater % Capital Value Example Office Building: Auckland & Wellington -- $59,000,000 Capital Value 28,000 kl/year Total VISIBLE cost / year Total cost / year Charge Total cost / year Total VISIBLE cost / year $43 $43 Annual Service Fee $100 $100 $36,400 $36,400 Ingoing Water $48,020 $48,020 $85,176 $85,176 Outgoing Wastewater $76,801 $ - $121,620 $121,620 $124,921 $48,120

9 Background: Doctoral Studies: Understand Water Use Increase Awareness Implementation Outputs: PhD Thesis (VUW) Calculator Tool (WERT) Bright Ideas Challenge Field Study: 36 AKL Office Buildings 57 WLG Office Buildings 2009 to 2011 What is the feasibility of RWH & GWR systems?

10 Research Streams: Social & Policy drivers and barriers perceptions experiences Buildings practical investigations feasibility assessment business case water quantity and quality Water Networks impacts regional consistency charging mechanisms

11 Online Survey Summary: Perception and opinion Drivers and barriers Experience, operation and maintenance Feeds other research streams 72 respondents building owners and managers building occupants product, equipment and service suppliers interested in RWH and/or GWR other Self-selecting sample

12 Online Survey Summary: >50% said RWH is acceptable for all water uses >70% said GWR is acceptable for toilet flushing & irrigation Top Incentives for: RWH: cost savings, sustainability and resilience GWR: sustainability, impact on supply and cost savings Lowest attraction was marketability (i.e. GSNZ) Biggest Barriers for: RWH: storage, cost and education GWR: education, regulations and water quality concerns Lower perceived understanding of GWR than RWH Opportunity for innovation in product, technology and expertise

13 Key Questions: 1. Water Quality 2. Education & Awareness 3. Resource Consumption 4. Feasibility - Acceptable vs. Actual? - Health Impact Assessment? - Available Information (including Legislation)? - Level of Understanding? - Building Water & Energy Use? - Rainwater & Greywater Savings? - Financially? - Operationally? 5. Issues & Considerations - Industry Status & Performance? - Design Implications?

14 Research Streams: Social & Policy drivers and barriers perceptions experiences Buildings practical investigations feasibility assessment business case water quantity and quality Water Networks impacts regional consistency charging mechanisms

15 Commercial Office Building Water Use: Image Source: Sydney Water Corporation, 2007

16 Commercial Office Building Water Use: Image Source: Sydney Water Corporation, 2007

17 Commercial Office Building Water Use: Image Source: Sydney Water Corporation, 2007

18 Opportunities for Rainwater Use: USE: 82% could be supplied by RWH

19 Opportunities for Greywater Use: Image Source: Sydney Water Corporation, 2007 SOURCE: 30% could be re-used

20 Opportunities for Greywater Use: 30% 30% USE: 30% could be supplied by GWR Image Source: Sydney Water Corporation, 2007 SOURCE: 30% could be re-used + 21%

21 Building Investigations: 1. Building Recruitment 2. Water Audit: a. RWH &/or GWR Collection & Storage b. Water End-uses c. HVAC Equipment d. Water Meter 3. Climate Data 4. Floor Plans & Water Reticulation Plans/Schematics WE NEED YOU! 5. Water Quantity Data & Quality Testing 6. Analysis via. Benchmarking & Feasibility 7. Building Reporting

22 Identification of Commercial Buildings:

23 Identification of Commercial Buildings: Regions with Universal Water Metering

24 Identification of Commercial Buildings: Regions with Universal Volumetric Wastewater Charging

25 Identification of Commercial Buildings: Six buildings successfully recruited into study

26 Monitored Water Use: Auckland saving $14,600/year in water bills Canterbury non-volumetric charging

27 Monitored Water Use: Auckland saving $14,600/year in water bills Canterbury non-volumetric charging potential greywater

28 Decision: Client Requirements Financial Benefit GSNZ Sustainability Profile Other? Resilience Network Design

29 Simple Payback: Bay of Plenty Payback: ~14 Year Capital Cost

30 Issues & Considerations: parking space VS. storage space data?? staff perception

31 Water Metering & Monitoring: SENSUS HRI-620 Pulse Sensor BRANZ Pulse Logger Range of Sub-Meters SENSUS 620 Water Meter

32 Time-of-Use Profiles: Wellington

33 Time-of-Use Profiles: Wellington

34 System Feasibility: Water charging mechanism dependent! A LOT more work to get accurate & robust answers!! Energy increase or reduction Floor area ratio Health impacts assessment Climate analyses Water source analyses Cost benefit analysis Reporting metrics O&M requirements Testing of feasibility model on other buildings Working paper Industry needs YELLOW FORMS

35 Research Streams: Social & Policy drivers and barriers perceptions experiences Buildings practical investigations feasibility assessment business case water quantity and quality Water Networks impacts regional consistency charging mechanisms

36 Impacts on Water Networks: Potable Water Wastewater

37 Impacts on Water Networks: Potable Water Wastewater Stormwater

38 Impacts on Water Networks: Potable Water Wastewater Rainwater Storage Tank Stormwater

39 Impacts on Water Networks: Potable Water Wastewater Rainwater Storage Tank Stormwater

40 Impacts on Water Networks: Potable Water Wastewater Rainwater Storage Tank Stormwater

41 Impacts on Water Networks: Potable Water Wastewater Rainwater Storage Tank Stormwater

42 Impacts on Water Networks: Greywater Potable Water Wastewater Rainwater Storage Tank Stormwater

43 Impacts on Water Networks: Greywater Potable Water Wastewater Rainwater Storage Tank Stormwater

44 Impacts on Water Networks: Greywater Potable Water Wastewater Stormwater

45 Impacts on Water Networks: Greywater Potable Water Wastewater Stormwater

46 Research Streams: Social & Policy drivers and barriers perceptions experiences Buildings practical investigations feasibility assessment business case water quantity and quality Water Networks impacts regional consistency charging mechanisms

47 More Information: Webpage: Contact Us: Next Steps: Building Recruitment & Monitoring Feasibility Analysis Water Network Modelling Advisory Panel Workshop 14 th July 2015 Strategic Framework + Feasibility Model + BRANZ Study Report

48 Thank You