Urban Water Security Research Alliance Implications of - PowerPoint PPT Presentation

Urban Water Security Research Alliance Implications of Resource-Efficient Technology on Peak Water Demand and Water- Related Energy Demand Rodney Stewart and Cara Beal South East Queensland Residential End Use Project 20 June 2012

PRESENTATION SCOPE • PART 1 -Water-related energy consumption and savings (Beal, C.D., Stewart, R.A., Bertone, E., (2012) Evaluating the energy and carbon reductions resulting from water- related stock efficiency. Buildings and Energy , under review.) • PART 2 - Peak demand analysis of SEQREUS ( Beal, C.D., Stewart, R.A., (2012) Identifying residential water end uses underpinning peak day and hour demand. Journal of Water Resources Planning and Management , under review.) • PART 3 – General conclusions

PRESENTATION SCOPE PART 1 - Water-related energy consumption and savings • Background - why do this work? • Methods - for acquiring the water end use data and energy data • Results – energy and GHG emissions • Results – intervention scenarios • Conclusions – transferring findings into practical policy outcomes

BACKGROUND – why do the study? • The nexus of water and energy and GHG emissions well recognised • Adoption of water-efficient technologies is imperative in reducing residential water-related energy demand • Quantifying the energy savings from (hot) water-efficient technologies has been largely based on modelled or assumed data (e.g. water use of fixtures/appliances, hot water system (HWS) type, % use of hot water) • Therefore, aim is to determine water, energy and GHG emission savings from resource-efficient household stock using: • empirical water end use data • detailed stock specifications and usage patterns

BACKGROUND – overview • The South-East Queensland Residential End-Use Study (SEQREUS) • Installation of smart meters and data loggers in 252 households in four regions of SEQ • Produced a detailed registry of water end-uses (micro- components) over 18 month period • Information from household water stock – e.g. clothes washing machines, hot water systems, shower flow rates etc. • Data used to calculate energy demand from each water appliance/fixture • Savings determined from substituting with water/energy efficient appliance/fixture

STUDY AREAS Sunshine Coast Regional Council (Noosa, Caloundra, Maroochy) Brisbane City Council Ipswich City Council Gold Coast

SEQREUS MIXED METHOD Taken from aligned project CSIRO

METHODS – energy and GHG emission data • Energy demand determined using published * energy intensity values (Wh/L) x known (measured) average water volume (L) of each end-use, for each home. • Energy use values were converted into GHG emissions using published GHG emission factors and methods presented in the Australian National Greenhouse Accounts report 2011 • A number of scenarios were devised to determine the impact on carbon emission reductions from various water and energy-efficient technologies. • Percentage savings from the base case scenario (worst case scenario of no efficient strategies and electric HWS) were calculated when comparing to a range of sequentially applied water and energy efficiency intervention strategies. *Details: Beal, C.D., Stewart, R.A., Bertone, E (2012) Evaluating the energy and carbon reductions resulting from water-related stock efficiency. Buildings and Energy , submitted Apr 2012

METHODS – energy and GHG emission data • Clothes washers: Table 1: Number of washing machines for each HWS, water connection and wash cycle category: Hot water system type Wash cycle Solar (Electric temperature Electric cylinder Gas storage Boosted) typical setting Single Dual Single Dual Single Dual Cold 23 86 2 8 8 22 Warm/Hot 8 23 0 2 0 7 ‘Single’ refers to a single cold water tap connection to washing machine, where hot water is sourced from internal heating within the machine. ‘Dual’ refers to both a cold and hot water tap connection to washing machine, where the hot water is sourced from the external hot water service and not from internal heating.

METHODS – energy and GHG emission data • Hot water systems: Table 2: Energy intensity and GHG emission conversion factors used for calculating GHG emissions savings for HWS Number GHG emission factor Energy in sample (kgCO 2 e/kWh) HWS type intensity (% total) (kWh/kL) A 177 (65) 1.0 B Electric 126.80 22 (8) Gas Cylinder 171.23 0.197 C 11 (4) 0.197 C Gas Instant 85.60 56 (21) Solar (electric 0.138 D 59.19 boosted) 5 (2) 22.09 E 0.500 F Heat pump 1 Kenway et al. (2008) except heat pump values; 2 DCCEE (2011) assuming 100% supply from coal-fired power station; 3 DCCEE (2011) for natural gas; 4 assumes insufficient insolation for 10% of the year due to cloud cover (i.e. 0.038 (DCCEE 2001) + 0.1 × 1.00), 5 heat pump energy intensity based on coefficient of performance, 6 assumed a 50% reduction in coal-fired electricity generation (Blum et al. 2010, Lund et al. 2004). *Details: Beal, C.D., Stewart, R.A., Bertone, E (2012) Evaluating the energy and carbon reductions resulting from water-related stock efficiency. Buildings and Energy , submitted Apr 2012

METHODS – intervention scenarios Table 3 Scenario Intervention Assumptions number scenario a) Solar panels with electric-boosted storage system; b) direct replacement of Conversion to electric HWS; c) long term average solar radiation data taken from Brisbane S1 energy-efficient airport and assuming same characteristics across SEQ d) 38 days or 10% of solar HWS year with insufficient insolation. a) Substitute high flow shower head with low flow shower head of flow rate at Water-efficient S2 0.09 L/s; b) co-efficient of 1.2 applied to compensate for increased duration shower heads due to lower flows. S2 + Water- a) CW internally heats cold water; b) front load only; c) cold water connection S3 efficient clothes only; d) directly substituting dual connected front or top load CW. washer S3 + Tap S4 a) Tap flow rate fixed value of 0.08 L/s (Australian Government 2011) aerators S4 + Shower a) Original shower temperature set at 40˚C (Flower 2009); b) existing shower temperature S5 head efficiencies (e.g. low or high flow roses) remain. reduced to average of 37 C˚ S5 + Energy- a) > 3 star rated machines considered ‘energy - efficient’; b) two efficiency efficient S6 clusters generated from SEQREUS data: ≤ 3 star and >3 star rated. dishwashers (DW) *Details: Beal, C.D., Stewart, R.A., Bertone, E (2012) Evaluating the energy and carbon reductions resulting from water-related stock efficiency. Buildings and Energy , submitted Apr 2012

RESULTS – water-related energy & GHG emissions Dish (a) Energy - Electric cylinder (EC) Dish (b) Carbon - Electric cylinder (EC) washer* washer* 81.9 81.9 kWh/p/y kg Shower (5.6%) CO 2 e/p/y 810 Shower (5.6%) kg Irrigation Clothes 810 Leaks CO 2 e/p/y Clothes washer 2 kL/p/y kWh/p/y 3.2 kL/p/y (55.5%) washer 104 (55.5%) (4%) (7%) 104 kWh/p/y Bathtub Dish kg (7.1%) 0.5 kL/p/y Toilet washer 1.2 CO 2 e/p/y Taps Taps (1%) 7.5. kL/p/y (7.1%) kL/p/y 464 464 kg (16%) (3%) kWh/p/y CO 2 e/p/y (31.8%) (31.8%) Clothes washer Electric cylinder (coal-fired power) HWS Shower 8.9 kL/p/y 13.9 (19%) (h) Carbon - Solar electric boosted (SEB) (g) Energy - Solar electric boosted (SEB) kL/p/y (30%) Dish Taps washer* Dish 9.5 kL/p/y 81.9 Shower washer* kWh/p/y (20%) 351 81.9 (10.3%) kWh/p/y kg (44.4%) CO 2 e/p/y Shower 48 Water end-use breakdown (45.3%) kg Clothes washer CO 2 e/p/y Taps (26.5%) 125 Clothes 234 kWh/p/y Taps washer kWh/p/y (15.8%) 34 kg 17 (29.5%) CO 2 e/p/y kg (18.8%) CO 2 e/p/y (9.4%) Solar (electric boosted) HWS

RESULTS – energy intensity Electric cylinder Hot water sourced from HWS Water internally heated by machine • Clothes washer configuration important: Warm/hot wash sourced from HWS = h energy use than internally heated water • DW energy intensity h , but low water demand reduces overall use demand

RESULTS - Impacts of scenarios Electric cylinder - Energy Solar power (EB) - Energy Cumulative reduction as each scenario applied S1 Conversion to energy-efficient solar HWS S2 Water-efficient shower heads S3 S2 + Water-efficient clothes washer (single, cold, front) S4 S3 + Tap aerators S4 + Shower temperature reduced to average of 37 C˚ S5 S6 S5 + Energy-efficient dishwashers (DW)

RESULTS - Impacts of scenarios Electric cylinder - Energy Solar power (EB) - Energy Solar power (EB) – GHG Emissions S1 Conversion to energy-efficient solar HWS S2 Water-efficient shower heads S3 S2 + Water-efficient clothes washer (single, cold, front) S4 S3 + Tap aerators S4 + Shower temperature reduced to average of 37 C˚ S5 S6 S5 + Energy-efficient dishwashers (DW)

RESULTS – Individual savings In Qld it is mandatory to install water and energy-efficient fixtures in new buildings – ‘Queensland Development Code’ Table 4. % individual savings (person/year) Scenario Water Energy reduction (%) reduction (%) Solar HWS (EB) - 46 Water-efficient shower 37 63 head Water-efficient clothes 27 87 washer  Tap aerators 27 38 Shower temp reduced to - 13 37C Energy-efficient dish - 28  washer