Showerhead amenities for reduced energy use and standardization of hot water conservation

26 Pages·2013·1.22 MB·English

Showerhead amenities for reduced energy use
and standardization of hot water conservation
Masayuki Mae Associate Professor, The University of Tokyo
Akinori Suzuki Tokyo Gas Company, Ltd.
Yuhi Murakami Graduate student, Tokyo University of Science
Yuki Mori Graduate student, Tokyo University of Science
Takashi Inoue Professor, Tokyo University of Science
Shizuo Iwamoto Professor, Kanagawa University
Takashi Kurabuchi Professor, Tokyo University of Science
Masayuki Otsuka Professor, Kanto Gakuin University
Japan Valve Manufacturers’ Association
Nov 3-5, 2013 At ACEEE Hot Water Forum, Atlanta, GA
Energy consumption trends in Japan
Revised energy standards, resulting from the Great East Japan Earthquake
Drastic enhancement of energy-saving and power-saving measures
（1018J） (兆円、2005T年ri価ll格io）n yen
18 600.0
Increase
16 x2.4 from increased (Fiscal 1973
→2011)
GDP, 1973–2011 500.0
14
23.3% x1.9
Transport
12 400.0
1016.4% Business 19.6%
x2.8
300.0
9.2%
8 Residential x2.4
8.9%
14.2%
6 200.0 x2.1
42.8%
465.5% Industrial
100.0
2 x0.9
0 0.0
73 75 80 85 90 95 00 05 11
（年度）
Fisical year
Source: Energy Whitepaper 2013, METI
・Industrial sector: Improved energy savings as a result of oil shock; 0.9 times 1973 level
・Civilian sector: Seeking increased convenience and comfort; 2.4 times 1973 level
2
Residential energy consumption in Japan
Energy-saving measures are needed in the civilian sector
From regulation of only residential insulation to primary energy regulation
Residential energy consumption breakdown Hot water consumption, 4-member family (n=47)
110000%%
Non-bath
9900%%
faucet
Lighting, etc. Hot water
8800%% 108L
34.7% 28.3%
7700%%
Bath
Fiscal 2011 60%
60%
38,358× 50%
50%
Cooling 120L
106 J/home
40%
40%
2.2%
30%
30%
Kitchen Shower
Heating
20%
20% 149L
8.1%
28.3%
10%
10%
0%
0%
Source: Energy Whitepaper 2013, Agency for Natural Source: Nakahama et al. (2009) “Measurement of bathtub water
Resources and Energy consumption for bathing (Part 4),” Proceedings of the Air
3
Conditioning and Sanitary Engineers Annual Meeting
Residential energy reduction attempts in Japan
Oil shock
1980 (Old) energy conservation standards
Rational use of
New energy-saving standards
1992
energy resources
1999 Next-generation energy-saving standard
2006
Revision
Introduction of (voluntary) standards, based on judgment of home builders
2009
Revision ・ Definition of hot water equipment (standards A (manual cutoff) / B (low flow spout))
・Addition of primary energy consumption standard to insulation standards
2013 Amended energy conservation standards
Strengthened residential standards for primary energy consumption in addition to envelope
thermal performance
Hot water / AC / Ventilation / Lighting / Elevators
Meeting standards requires… High energy-saving effects for construction
・High-efficiency water heaters costs; rapid adoption expected
・High-insulation bathtubs
Water-saving standards A1 (manual) / C1 (water priority spout)
・Solar water heaters
・Installation/replacement of low- Reconsideration of standard B1（low-flow spout)
use hot water equipment
New consideration of standard B2 (revised low-flow spout)
Currently, best-effort; mandatory in 2020
4
Low-flow water discharge standards in Japan
(2009 measurement method)
Voluntary amenity standards by the Japanese Valve Manufacturers' Association
Quantitative metrics under consideration for standardization
Flow
Definition Less Flow rate [L/min] More
Min. usable flow Min. satisfactory flow Optimal flow Max. satisfactory flow Max. usable flow
Flow (1) Optimal flow (initial) Optimum flow rate is the average of ​​(1), (4), and (7)
measurement(2) Max. satisfactory flow
method Reason: 1. Taking the mean of optimal flow (1), (4), and (7)
(3) Max. usable flow
considers variation due to measurement conditions.
(4) Optimal flow (4) is likely overly large, (7) overly small.
(5) Min. satisfactory flow 2. (2)(3)(5)(6) not needed for water reduction
(6) Min. usable flow devices, but measured to compensate for variation
in perceived optimal flow rate.
(7) Optimal flow
Reduction
Avg. optimal flow as measured by monitor
) x 100
Reduction ratio = (1 –
Current typical flow rate (10 L/min)
Conditions Shower sprayed onto chest area
Test conditions
Reason: Sprayingon face is likely to result in lower flow than in typical use
At least 10 subjects, approx. equal division of sexes
Subject conditions
Reason: To prevent differences in sprayamounts due to sex
Source: Japan Valve Manufacturers' Association http://www.j-valve.or.jp/ 5
Japanese shower standards
Standard of Judgment for Residential Low-energy standards for homes and buildings
Standard
Construction Clients （2009） Energy code 2013
Items fulfilling reduction standards according to
Items meeting standards for low-water
Definition the monitoring method established by the Japan
construction
Valve Manufacturers Association
Certification Manufacturer measurement and evaluation JIS measurement and certification
Water is easily stopped by manual operation 20% reduction
Switch
Push button faucet
Manual
stoppage
(Type A)
Switch shower
t
c
e
f
f
e Optimal flow of 8.5L/min or less

d
n
a 15% reduction

e Low-flow Spray shower Low-flow faucet standards
p
y (Low-Flow)
T faucet
currently being established
(Type B)
Combined 32% reduction Currently being established
6
Source: Japan Valve Manufacturers' Association http://www.j-valve.or.jp/
International shower standards
Japan: Evaluation of optimal flow based on industry standards (enacted 2009, voluntary)
US, EU, etc.: Regulations and restrictions based on physical quantity measurements
Highly reproducible water discharge force standards that preserve amenity are needed (2013)
FLOW RATE OTHER REQUIREMENTS STANDARD
Japan Mandatory 2013 Currently, best-effort; mandatory in 2020
Voluntary Common: 10L/min(Optimal flow rate) Effectiveness and comfort Japan Valve
Hot water saving: Type A ⇒Quick-stop Function Optimum pressure calculated Manufacturers’
Type B ⇒8.5L/min(Optimal flow rate) Association
2009
Type A B ⇒Type A and Type B
USA Mandatory Common: Max. 9.5 L/min(2.5 gpm) at 550 kPa Spray force: Min. 0.56 N (2.0 oz) @ 140 ANSI/ASME
High efficiency: Max. 7.6 L/min (2.0 gpm) kPa A112.18.1
Min. 75% of max. at 550 kPa Spray coverage: ≤75% (φ50～100mm)
75% of max. at 410 kPa ≥25% (φ50～150mm)
60% of max. at 140 kPa
Voluntary Max. 7.6 L/min (2.0 gpm) EPA
Min. 75% of max. at 550 kPa WaterSense
75% of max. at 310 kPa
60% of max. at 140 kPa
High efficiency (prerequisite):7.6 L/min (2.0 gpm) LEED (2009 v3)
Very high efficiency (2pt): 6.6L/min (1.75 gpm)
EU Mandatory Water run through apparatus and flow rate calculated Thermal shock test EN1112
Type 1: (0,3 + 0,02) MPa (3 + 0,2) bar Leakage test (2008)
Type 2: (0,01 + 0,005) MPa (0,1 + 0,05) bar Mechanical strength test
Record flow rate Qafter stabilization Rotary connectiontest
Voluntary Min. flow rate: 6 L/min; max. flow rate: 12 L/min. Aand B WELL (2011)
Rating two criteria: volume and temperature
two stars for each evaluation criterion is the best possible.
7
A= Maximum efficiency at approx. 6L/min <9L B=>9L<12L
Problems in previous cases
• Most showers in Japan are handheld
– Distance between showerhead and body is not fixed
• Excluding load of water droplets on plate
［°］ Testing Maker
66..00 T Co. K Co. S Co.
TOTO
]
.55..00 KVK
g
e
三栄水栓
d
[44..00

n
o
it33..00
u
l
o
v22..00
e
r

e11..00
t
Water receiving plate a
l
P
00..00
AS BC -C -D EX -F GC HC 0I JG K社 L社 M社
U.S. EPA evaluation testing #1 re05 -SM 50-2X 50-0X -80 GB-X -70 -24 C1- -75 -販A -販B -販C
wZ9 05 398 398 B- 2980 H7 HC TH Y4 通 通 通
（Watersense） o 9 S S 1 3 T T H
h Z 3 S T
S
S
13 retail market showerheads (sample)
Source: Japan Valve Manufacturers' Association http://www.j-valve.or.jp/ 8
Studies on physical properties of showers
(Japan)
“Experimental Study on the Usability of Residential Hot Water Supply System :
Part 2-Showering and Bathing” (Kamata et al.)
Optimal shower flow rate is proportional to the nth power of the total hole area
𝑛
𝑄 = 𝐶𝐴
𝑇
𝑄 …Optimum flow 𝐶，𝑛 …Experimental constants 𝐴…Total hole area
𝑇
Need to analyze low-water showerheads implementing various
mechanisms
“A Study on the Design Requirements of Equipment for Taking a Shower”
(Murakawa et al.)
Measurement perpendicular to spray force
“Study on methods of designing shower heads” (Kondo et al.)
Measurement 45° to spray force
Need to exclude factors affecting load other than shower spray
9
Spray force test conditions (current draft)
Spray
Horizontal direction
Suppress influence of water load
Receiving plate
Dimensions: 200×200 mm, t = 3 mm
Material: Acrylic
Spray force measurement device
Rated capacity: 20 N
Resolution: 0.01N
Precision: ±2% FS
Sampling period: 50ms
Spray distance (to receiving plate) Spray adhesion point
(central)
150±15mm
Spray angle
Spray adhesion point (central)
(a)
(b)
Permissible range (a): 0±20mm
Spray angle
Permissible range (b): 0±15°
Flow rate
7.0, 8.5, 10L/min Permissible range: ±0.2L/min
10