Slide 1 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Low-flow Showerheads for Residential and Select Commercial Applications Danielle Gidding Bonneville Power Administration Ryan Firestone Navigant Consulting February 2, 2010

Slide 2 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Purpose Approval of low-flow showerheads: Flow-rates –2.0 gpm –1.75 gpm –1.5 gpm Sectors –Residential –Commercial Hospitality Health Care Small Commercial with Employee Shower Delivery Mechanisms –Direct Install –Retail and Mail-by-Request (Residential only)

Slide 3 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Agenda Background –Low-flow showerhead background –Current deemed measure Residential Showerheads –Assumptions and savings from current deemed measure –Proposed modifications to current assumptions –Proposed parameter values for lower-flow showerheads –Potential savings impacts Commercial Showerheads –Proposed assumptions and analysis approach Research Plan –Use direct install measure as vehicle to collect data for measure analysis update Proposal

Slide 4 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Background Pre 1992 – Showerheads capable of 4-5 gpm (or more) –Typically throttled to ~3.2 gpm 1992 EPAct – 2.5 gpm maximum flow rate, at 80 psi 1990’s – conservation efforts (primarily water) distribute EPAct qualifying showerheads en masse – Seattle – 2.5 gpm average in situ flow rate, 2.2 gpm median. Comparable to studies in other regions 2009 – Miami-Dade County, Florida – limits flow rate to 1.5 gpm, distributes compliant showerheads – U.S. EPA to release WaterSense performance specifications for showerheads ≤ 2.0 gpm. (latest estimate is March)

Slide 5 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Current Deemed Measure RTF initially deemed in 2007 –Current baseline assumption is customer average showerhead flow rate of 2.2. gpm This implies average rated flow rate is slightly less than 2.5 gpm. –Residential applications – Retrofit existing showerheads with ≤2.0 gpm rated showerheads –Current measures assumes 2.0 gpm rated (1.8 gpm in situ) No additional savings for lower flow rates –Shower prominence - {primary, secondary, any } –Water heater fuel - {electric, gas, any} –Savings based on engineering analysis, informed by end-use study in 2000, survey of in situ flow rates of existing and low-flow (2.0 gpm) showerheads in –Incentives provided for 66,000+ showerheads from BPA Since average MW

Slide 6 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Current RTF Measure Eligibility “Replacement showerhead shall be pressure-compensating with non-removable flow controller and have flow rate of 2.0 gpm or less as tested at 80 psi (552 kPa) in accordance with ANSI standard A M. Showerhead shall be installed by utility staff or utility contractor or delivered to the consumers in fulfillment of their request. Limited to two (2) showerheads per residence.”

Slide 7 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Current RTF Baseline Assumptions

Slide 8 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Current RTF Baseline Assumptions Measure Cost: $24 (includes material and distribution) Measure Lifetime: 10 years Water Cost: $10.03 / 1000 gallons Water energy intensity: 5.3 kWh / 1000 gallons

Slide 9 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Current RTF Savings The five year regional savings potential is 85 average MW

Slide 10 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Adjustments to Current 6 th Plan Measure – Residential Showerheads Proposed changes Baseline adjustment New showerhead ratings –greater than 1.75 gpm, less than or equal to 2.0 gpm –greater than 1.5 gpm, less than or equal to 1.75 gpm –less than or equal to 1.5 gpm Potential impacts to savings from lower flow rates

Slide 11 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Baseline Adjustments Baseline is primarily unchanged from current measure Recommend updating the hot water percentage assumption –Currently assumes average user setting of 105°F –More recent study* found 108°F * Mayer, P. W., DeOreo, W. B., & Lewis, D. M. (2000). Seattle Home Water Conservation Study. Seattle Public Utilities and the U.S. EPA.

Slide 12 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Baseline Adjustments

Slide 13 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Potential Impacts to Savings In order to define savings by gpm < 2.0, need to address the following issues: –In situ flow rate –Shower duration –Temperature set-point –Uptake Satisfaction Scalding

Slide 14 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N What is the actual flow rate once installed? –Showerheads are rated for 80 psi, residential average ~65 psi. Flow rate decreases as pressure decreases –Field studies typically observe in situ flow rate ~90% of rated* For example, a 2.5 gpm rated showerhead will have an average in situ flow rate of 2.25 gpm. –Current and proposed measure require pressure-compensation. There are currently no performance specifications for this claim. US EPA WaterSense specifications due out in March 2010 –>60% of rated flow rate between 20psi and 80psi –>75% of rated flow rate between 45psi and 80psi *Schuldt, M., & Tachibana, D. (2008). Energy-Related Water Fixture Measurements: Securing the Baseline of Northwest Single Family Homes. Proceedings of the 2008 ACEEE Summer Study on Energy Efficiency in Buildings. ACEEE. In Situ Flow Rate

Slide 15 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Recommendations: –Maintain 10% de-rating of rated flow rate for all calculations, all flow rates In Situ Flow Rate

Slide 16 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Do lower flow rates result in longer showers? Field studies have not shown statistically significant increase in 2.5gpm to 2.0 gpm retrofits –For example, SPU study in 2000: 7.91 minutes baseline, 7.84 minutes post retrofit, difference not statistically significant* Effect may be present, but has not been quantified * Mayer, P. W., DeOreo, W. B., & Lewis, D. M. (2000). Seattle Home Water Conservation Study. Seattle Public Utilities and the U.S. EPA. Shower Duration

Slide 17 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Recommendation: For 2.0 gpm showerheads, assume no increase in shower duration from baseline (7.84 minutes) For 1.75 and 1.5 gpm, increase duration assumption by 5% and 10%, respectively Shower Duration

Slide 18 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N How does lower gpm affect water temperature? Smaller droplets and less absolute water volume decrease water temperature experienced Increase in temperature set-point has been observed for 2.2 gpm (108°F) to 1.8 gpm (110°F)* *Mayer, P. W., DeOreo, W. B., & Lewis, D. M. (2000). Seattle Home Water Conservation Study. Seattle Public Utilities and the U.S. EPA. Temperature Set-Point

Slide 19 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Recommendation: Assume observed values for baseline and 2.0 gpm Assume linear increase in hot water percentage at lower flow rates. Temperature Set-Point

Slide 20 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Delivered Showerheads Installed How many showerheads stay installed? User satisfaction is indirectly correlated to flow rate Recommendation: Direct Install Keep current measure assumption of 90% to account for potential change-out Retail/Mail by Request Reduce install percentage to account for non-feasible applications (unacceptable temperature variation) and sub-optimal installations

Slide 21 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N RTF should be aware of this issue Pressure disturbances (e.g. toilet flush) cause an imbalance of hot/cold water at the fixture. Most U.S. codes since 1987 require automatic-compensating mixing valves (thermostatic, pressure balancing, or combination), to work with dev ices rated at 2.5 gpm, 45 psi –Performance may decrease at lower flow-rates No public records documenting reduced flow rate that contribute to accident, or product recall –At least several conservation programs currently distributing sub-2.0 gpm showerheads. US EPA WaterSense documentation discusses the potential, but will certify sub-2.0 gpm showerheads Thermal Shock and Scalding

Slide 22 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Treatment and Recommendation: Tested for during direct install (measure specification) Programs should ensure adequate documentation of risks Recommend that water heater temperature setpoint be checked and set to 120°F or less Reduce % of delivered showerheads installed for retail and mail-by-request to account for unacceptable temperature variation Thermal Shock and Scalding

Slide 23 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Residential Cost and Measure Life Measure Cost $24 retail and mail by request (same as current PTR measure) $31 direct install –Cost includes labor time (20 $20/hour) to replace, test for acceptable thermal variation, test flow rate, collect data for annual utilization –Data collection will be used to update assumptions used in savings analysis Measure Life 10 years (same as current PTR measure)

Slide 24 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Savings and Cost Effectiveness – Residential Direct Install

Slide 25 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Savings and Cost Effectiveness – Residential Retail and Mail-by-Request

Slide 26 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Commercial Showerheads Requesting Provisionally Deemed Savings for direct install measures for: Hospitality (hotel/motel) Hospitals Small commercial employee showers Research Required for full deeming Determine baseline flow rate in above commercial applications Usage information to determine annual utilization (minutes/year) of showerhead Residential values assumed for all other parameters

Slide 27 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Commercial Analysis Use residential analysis assumptions for flow rates, temperature, cost. Adjust showerhead utilization (minutes/year) by business type Recommended baseline data collection for provisionally deemed measure: –Flow rate (pre and post retrofit) –Parameters used to derive annual utilization

Slide 28 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Commercial Baseline – Annual Utilization

Slide 29 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Commercial Baseline – Annual Utilization

Slide 30 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Commercial Baseline – Annual Utilization

Slide 31 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Commercial Savings Assumptions Same post-retrofit assumptions as residential:

Slide 32 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Savings and Cost Effectiveness – Commercial Direct Install

Slide 33 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Provisionally Deemed Research Plan Use direct install program as vehicle for data collection for savings update Collect baseline information during retrofit for savings update –flow rate –water pressure –information used to derive utilization (min/year) occupancy rates, # of users per shower showers/person/day (if known) shower duration (if known) Recommended sunset date (18 months)

Slide 34 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Request for RTF Approval 1) Residential Direct Install –Deem savings values for the three flow rates specified –For direct install, require pre/post data collection at time on install to update baseline Retail and Mail-by-Request –Deem savings values for the three flow rates specified Five year sunset for by delivery mechanisms 2) Commercial Direct Install –Provisionally deem savings values for the three flow rates specified for 18 months

Slide 35 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Discussion

Slide 36 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Backup – Commercial Retail and Mail-by- Request Results

Slide 37 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Backup – Residential Baseline Analysis

Slide 38 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Backup – Commercial Baseline Analysis

Slide 39 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Backup – Residential Retrofit Gross Analysis

Slide 40 B O N N E V I L L E P O W E R A D M I N I S T R A T I O N Backup – Commercial Retrofit Gross Analysis