Chapter : 4 Water Efficiency 1 © 2015 Green Building Academy. All rights reserved.

Disclaimer LEED® and USGBC® are registered trademarks of the U.S. Green Building Council. The author is not affiliated to USGBC or GBCI. The information provided in the presentation are compiled by the author and is not endorsed by USGBC or GBCI 2 © 2015 Green Building Academy. All rights reserved.

3 CREDITTITLENCCSSc Rt HcHsDCWD WE P1Outdoor water use reductionR WE P2Indoor water use reductionR WE P3Building – level water meteringR WE C1Outdoor water use reduction 212 WE C2Indoor water use reduction 676 WE C3Cooling tower water use 2 WE C4Water metering 1 © 2015 Green Building Academy. All rights reserved.

WE P1, C1 Outdoor water use reduction Design NCCSScRtHcHsDCWD Required 4 NCCSScRtHcHsDCWD 212 © 2015 Green Building Academy. All rights reserved.

Intent To reduce outdoor water consumption. 5 © 2015 Green Building Academy. All rights reserved.

Temporary Irrigation system – Upto 2 years -Prerequisite Requires selection of appropriate species which survives with rainfall Submit a narrative Projects without landscape automatically earn the prerequisite and credit Reduce 30% from Baseline – Prerequisite Reduce 50% - 1 Pt Reduce 100% -2 Pts (Except Health Care) 6 Option 1 – No permanent Irrigation System – 2 Pts Option 2 – Reduced Irrigation © 2015 Green Building Academy. All rights reserved.

7 US Projects: Use Interactive Water Budget tool Interactive water budget tool automatically takes ETo and Precipitation data from database based on zipcode International Projects to use excel version of the tool and manually feed ETo and precipitation data © 2015 Green Building Academy. All rights reserved.

8 Baseline Reference evapotranspiration rate (ETo) is the amount of water lost from a specific vegetated surface. Turf grass with height of 120 mm is the reference vegetation Reference Evapotranspiration is constant for a City/Town. Hot and dry climates have higher evapotranspiration compared to cool and humid climates For LEED Calculations ETo of the hottest month is considered for calculation. © 2015 Green Building Academy. All rights reserved.

9 Strategies & Implementation Demand reduction strategies: Use native & adaptive species Avoid invasive species. Reserve grass only for playfields and lawns where turf is absolutely necessary Efficient irrigation system. 30% reduction for prerequisite should be achieved only by demand reduction strategies Controls: Additional 15% reduction is water use can be achieved by Irrigation controls that meets water sense or equivalent criteria. Alternate Non Potable Water Sources: Treated storm water, gray water, reclaimed wastewater, gray water, municipally supplied treated wastewater, condensate drain from refrigeration and AC system or other process water with meets the water quality requirement Non potable water sources should be tested for acceptable salinity levels Choose the water source which require lesser treatment if many sources are available © 2015 Green Building Academy. All rights reserved.

10 Points to remember Athletic fields and playgrounds (if vegetated) and food gardens may be included or excluded at the project team’s discretion. If the project has both xeriscape and irrigated landscape, two calculations to be submitted for each landscape. © 2015 Green Building Academy. All rights reserved.

11 Documentation Option 1Option 2 Site plan showing vegetated areas √ Narrative for plant species and water requirements √ Site plan showing location and size of landscape zones √ Water Budget Tool report √ Alternative water source and controls calculations [Credit only] √ © 2015 Green Building Academy. All rights reserved.

WE P2, C2 Indoor water use reduction Design NCCSScRtHcHsDCWD Required 12 NCCSScRtHcHsDCWD 676 © 2015 Green Building Academy. All rights reserved.

Intent To reduce indoor water consumption. 13 © 2015 Green Building Academy. All rights reserved.

14 Requirements- prerequisite Plumbing fixtures AppliancesProcess 20% water use reduction from baseline All eligible plumbing fixtures must be water sense labeled Energy Star or Performance equivalent No once through cooling with potable water Makeup water meter Conductivity Controllers and overflow alarms Efficient drift eliminators © 2015 Green Building Academy. All rights reserved.

Cooling Tower Water to air Heat exchanger used in cooling plants, power plants etc to cool water. Analogous to outdoor unit in split air conditioner 15 © 2015 Green Building Academy. All rights reserved.

Once Through System 16 © 2015 Green Building Academy. All rights reserved.

17 Plumbing fixtures 20% water use reduction Prescriptive Path Performance path Each Plumbing fixture shall comply with the above flow rates Aggregate water consumption 20% lesser than baseline Use Indoor Water use calculator to demonstrate water use reduction Alternative water sources not considered as water use reduction in prerequisite © 2015 Green Building Academy. All rights reserved.

18 Requirements Path 1 – prescriptive (pre-requisite only) Ensure that all selected fixtures meet the following prescriptive flush or flow rate thresholds FixtureBaseline flush or flow rate (IP units) Maximum installed flush or flow rate (IP units) Threshold below code baseline Water Sense Label Available Toilet (water closet)1.6 gpf1.28 gpf20%Yes Urinal1.0 gpf0.5 gpf50%Yes Public lavatory faucet 0.5 gpm at 60 psi0.4 gpm20%No Private lavatory faucets 2.2 gpm at 60 psi1.5 gpm32%Yes Kitchen faucet2.2 gpm at 60 psi1.75 gpm20%No Showerhead2.5 gpm at 80 psi2.0 gpm20%Yes Compliance to be demonstrates by product cut sheets of fixture schedule © 2015 Green Building Academy. All rights reserved.

19 Water Sense Available Tank-type toilets (water closet) Water-using urinals Private lavatory faucets Showerheads Water Sense not available Tankless toilet Composting toilet Waterless toilet Waterless urinal Public lavatory faucet © 2015 Green Building Academy. All rights reserved.

20 Requirements All newly installed toilets, urinals, private lavatory faucets, and showerheads that are eligible for labeling must be WaterSense labeled (or a local equivalent for projects outside the U.S.). © 2015 Green Building Academy. All rights reserved.

21 Requirements- Credit (1-6 points) FIRST – 20% Only with Efficient fixtures Alternative water sources can be used for additional savings Janitor sinks and fixtures regulated by Health codes are not considered in calculation © 2015 Green Building Academy. All rights reserved.

22 Non-acceptable Alternate water sources: Untreated water sources ineligible for this credit include raw water from naturally occurring surface bodies of water, streams, rivers, groundwater, well water, and water discharged from an open-loop geothermal system. Acceptable Non-potable water sources: Treated storm water, gray water, reclaimed wastewater, municipally supplied treated wastewater, condensate drain from refrigeration and AC system or other process water with meets the water quality requirement © 2015 Green Building Academy. All rights reserved.

23 Calculations Calculations for the design case (installed) flush and flow fixtures. The following information is required: Fixture type Flush or flow rate Fixture manufacturer and model (which should match cutsheets) Percentage of occupants using each fixture model. The total for all fixtures of each type must total 100% of occupants for standard fixture types. © 2015 Green Building Academy. All rights reserved.

24 Calculations © 2015 Green Building Academy. All rights reserved.

25 Calculations © 2015 Green Building Academy. All rights reserved.

26 Calculations © 2015 Green Building Academy. All rights reserved.

27 Calculation Sample Calculation: 2 Women: water closet 3 uses per day 3 Men: water closet 1 use per day, urinals 2 uses per day Faucet: 3 uses per day per FTE, 30 seconds per use 2 FTE Woman X 1.6 gallons (water closet conventional flush rate) X 3 uses per day = 3.2 gallons/day 3 FTE Men X 1.6 gallons (water closet conventional flush rate) X 1 use per day = 4.8 gallons/day 3 FTE Men X 1.0 gallon (urinal conventional flush rate) X 2 uses per day = 6.0 gallons/day Sink Flow Rates 5 FTEs [(5 FTEs X 3 uses/day X 30 seconds)/ 60 seconds per minute] X 0.5 gallons per minute = 3.75 gallons/day = gallons Daily water use for each fixture type = Fixture flush or flow rate Duration of use Users Uses per person per day xx x © 2015 Green Building Academy. All rights reserved.

28 Appliance - Prerequisite © 2015 Green Building Academy. All rights reserved.

29 Process - Prerequisite © 2015 Green Building Academy. All rights reserved.

30 Appliance and Process- Credit SCHOOLS, RETAIL, HOSPITALITY, AND HEALTHCARE ONLY Table 2 - Compliant commercial washing machines(the project must process at least 120,000 lbs ( kg) of laundry per year) One point is awarded for meeting all applicable requirements in any one table. All applicable equipment listed in each table must meet the standard. Schools, Retail, and Healthcare projects can earn a second point for meeting the requirements of two tables. © 2015 Green Building Academy. All rights reserved.

31 Appliance and Process- Credit Table 3 - Standards for commercial kitchen equipment (the project must serve at least 100 meals per day of operation). © 2015 Green Building Academy. All rights reserved.

32 Appliance and Process- Credit Table 4 - Compliant laboratory and medical equipment (the project must be a medical or laboratory facility). Table 5 - Compliant municipal steam systems (the project must be connected to a municipal or district steam system that does not allow the return of steam condensate). © 2015 Green Building Academy. All rights reserved.

33 Points to remember Private faucets - Residential, Hotel guest room, hospital patient room If there any confusion for choosing faucet type, should go for public faucets. It is acceptable to use only water efficient aerators instead of complete fixture Aerators should be WaterSense or equivalent certified Water efficient showers and faucets require sufficient pressure for satisfactory operation. Especially in highrise buildings the plumbing fixture has to be balanced to ensure sufficient pressure is available for the fixture. © 2015 Green Building Academy. All rights reserved.

34 Documentation Achieve 55% savings. Exemplary Performance DocumentationFixturesAppliances Process water (Rt, HC, Hs and Sc projects only) Alternative water source calculations (if applicable) √ Plumbing system design drawings (if applicable) √ Alternative water narrative √ Cutsheets, manufacturers’ information √√√ Indoor water use calculator √ © 2015 Green Building Academy. All rights reserved.

35 Reference Standards Energy Policy Act (EPAct) of 1992 and as amended in EPAct 2005 International Association of Plumbing and Mechanical Officials Publication IAPMO / ANSI UPC , Uniform Plumbing Code 2006, Section 402.0, Water-Conserving Fixtures and Fittings International Code Council, International Plumbing Code 2006, Section 604, Design of Building Water Distribution System ENERGY STAR Energy Policy Act (EPAct) of 1992 and as amended IGCC/ASHRAE © 2015 Green Building Academy. All rights reserved.

WE P3, C4 Building – water level metering Design NCCSScRtHcHsDCWD Required 36 NCCSScRtHcHsDCWD 1 © 2015 Green Building Academy. All rights reserved.

Intent To support water management and identify opportunities for additional water savings by tracking water consumption 37 © 2015 Green Building Academy. All rights reserved.

38 Requirements(Prerequisite) Install permanent water meters that measure the total potable water use for the Buildings and associated grounds Commit to share whole-project water usage data for a five-year(or until building changes ownership or lessee) period beginning on the date the project accepts LEED certification or typical occupancy, whichever comes first. Data to be shared in USGBC-approved data template or Third-party data source Utility meter and monthly bills can be used to track water consumption Separate meters required, if more than one source of potable water(like well water) is used in the project Data compiled into monthly and annual summaries for sharing it with USGBC © 2015 Green Building Academy. All rights reserved.

39 Requirements- Credit Install permanent water meters for two or more of the following water subsystems, as applicable to the project: Irrigation – 80% of irrigated landscape Indoor plumbing – 80% of indoor fixture & fittings Domestic hot water – 80% of capacity Boilers if demand exceeds 100,000 gallons or 500,000BtuH Reclaimed water – 100% Other process water - 80% of expected daily consumption Consider subsystems based on consumption, cost of operation and that closely align with the goals of the building management. © 2015 Green Building Academy. All rights reserved.

40 Calculation / Documentation DocumentationAll projects Water metering strategy narrative √ © 2015 Green Building Academy. All rights reserved.

WE C3 Cooling Tower Water Use Design NCCSScRtHcHsDCWD 2 41 © 2015 Green Building Academy. All rights reserved.

Intent To conserve water used for cooling tower makeup while controlling microbes, corrosion, and scale in the condenser water system 42 © 2015 Green Building Academy. All rights reserved.

Cooling Tower Water to air Heat exchanger used in cooling plants, power plants etc to cool water. Analogous to outdoor unit in split air conditioner 43 © 2015 Green Building Academy. All rights reserved.

Drift: Water droplets carried from a cooling tower by a stream of air. Drift eliminators capture these droplets and return them to the system Evaporation: Evaporation is the main mode of heat transfer through which water looses the heat to air via latent heat Blowdown: As the water in cooling tower is lost by evaporation and drift, the salinity and hardness of recirculating water increases which may cause scaling in cooling tower. The process of discharging concentrated water is called blowdown. 44 Water loss in cooling tower © 2015 Green Building Academy. All rights reserved.

Makeup water: water that is fed into a cooling tower system or evaporative condenser to replace water lost through evaporation, drift, bleed-off, or other causes 45 (Make-up = evaporation + blowdown + drift) Cooling Tower contd. © 2015 Green Building Academy. All rights reserved.

Once Through System 46 © 2015 Green Building Academy. All rights reserved.

47 Requirements One-time potable water analysis (1-2 points) Measure at least the following five control parameters: Ca (as CaCO 3 ) Total alkalinity SiO 2 CI Conductivity © 2015 Green Building Academy. All rights reserved.

48 Requirements Maximum concentration for parameters in condenser water ParameterMaximum Level Ca (as CaCO 3 )1000 ppm Total alkalinity1000 ppm SiO ppm Cl ppm Conductivity2000 µS/cm © 2015 Green Building Academy. All rights reserved.

49 Requirements Calculate the number of cooling tower cycles by dividing the maximum allowed concentration level of each parameter by the actual concentration level of each parameter found in the potable makeup water. (Make-up = evaporation + blowdown + drift) © 2015 Green Building Academy. All rights reserved.

50 Strategies / Implementation Limit cooling tower cycles to avoid exceeding maximum values for any of these parameters. Maximize - Cycles of concentration Minimize - Blowdown Make-up water Use alternate sources of make up water – Air handler condensate – Cooling system water – Pre-treated effluent – Recycled wastewater – Rain water collected from roof Take expert advise in cooling tower design © 2015 Green Building Academy. All rights reserved.

51 Calculation Example: ParameterMaximum Level (1)Measured in makeup water (2) No. of cycles (1/2) Ca (as CaCO 3 )1000 ppm200 ppm5 Total alkalinity1000 ppm150 ppm6 SiO ppm5 ppm20 Cl ppm20 ppm12 Conductivity2000 µS/cm100 µS/cm20 5 cycles of concentration required (choose the least one) © 2015 Green Building Academy. All rights reserved.

52 Documentation 1 point2 points Potable water analysis results √√ Potable water analysis narrative √√ Cycles of concentration calculations √√ Non potable water calculations √ Water treatment calculations √ Nonpotable water analysis (if using 100% nonpotable water) √ © 2015 Green Building Academy. All rights reserved.

53 Questions? © 2015 Green Building Academy. All rights reserved.