presentation by: richard young
TRANSCRIPT
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Cold Hard Savings: How to Purchase and Operate Ice Machines
for Max Efficiency & Min Cost
February 18th 2014
Presentation by:
Richard YoungDirector of Education
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Who?
Specializing in commercial food service
Promoting energy efficiency and performance
Celebrating 26 years of hard work!
The Food Service Technology Center (FSTC) is an
unbiased energy-efficiency research program
funded by California utility customers.
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www.fishnick.com/handouts/02182014
Download Today’s Handouts:
Our Mission is to bring “MPG”
and Performance information to
the entire commercial food
service world.
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Today’s Learning Goals
1. How to use the AHRI database and the
California Energy Wise incentives to find
energy-efficient ice machines.
2. How to use the FSTC online calculator to
estimate energy savings for efficient machines.
3. Understand what it means to “load shift” an ice
machine and how to accomplish load shifting.
Part One: 9:30 to 10:45
Purchase and Calculate
Part Two: 11:15 to 12:30
Load Shifting
30 Minute Break
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Part One:
Purchase and Calculate
But First...
Some Background and Basics
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Our First
Restaurant Field Monitoring
Case Study
1. Increased ice machine capacity
2. Ice machine on a timer: runs only at night
From:
• 194 lb/day
• 12.2 kWh/100 lb
• 28.7gal/100 lb
• 18.6 kWh/day
• $880/year
• 570 lb/day
• 6.5 kWh/100 lb
• 26.4 gal/100 lb
• 7.25 kWh/day
• $ 340/year
To:
@ $0.13/kWh
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From: To:
Save $540 a year• quieter kitchen
• cooler kitchen
• more ice available
• reduce demand by 1 kW
That got us interested and we
started asking questions like...
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Who uses ice machines?
• Everyone:
Hotels, schools, hospitals, churches,
restaurants, businesses, biomedical,
government, correctional, etc...
• And, many restaurants have multiple ice
machines.
Back of the envelope estimate:
At least 3,000,000 ice machines in US
Then we discovered an important
and unique resource:
The AHRI Online Database
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AHRI Ice Machine Database
Air-Conditioning, Heating & Refrigeration Institute (AHRI)*
• Ice Harvest Rate (lb/24 hr)
• Potable Water Use Rate (gal/100 lb ice)
• Energy Consumption Rate (kWh/100 lb ice)
• Condenser Water Use Rate (gal/100 lb ice)
http://www.ahridirectory.org/ahriDirectory/pages/home.aspx
AHRI Directory of Certified Product Performance
ACIM – Automatic Commercial Ice-Makers* and Ice Storage Bins
* Changed from “Ice-Cube Machines” to now include continuous-type machines.
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0
2
4
6
8
10
12
14
16
18
0 500 1000 1500 2000 2500
Energy Consumption (kW
h/100 lb)
Ice Harvest Rate (lb/24 hr)
Air‐Cooled Cube‐Type Water‐Cooled Cube‐Type
AHRI Database
Observation #1:Higher capacity machines use
less energy per 100 lb of ice
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0
2
4
6
8
10
12
14
16
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0 500 1000 1500 2000 2500
Energy Consumption (kW
h/100 lb)
Ice Harvest Rate (lb/24 hr)
Air‐Cooled Cube‐Type Water‐Cooled Cube‐Type
AHRI Database
Observation #2:For a given capacity of machine,
energy use varies significantly
1994 ARI Data – Air-Cooled Cube Type
7.75
12
0
2
4
6
8
10
12
14
16
18
0 500 1000 1500 2000 2500
Energy Consumption (kW
h/100 lb)
Ice Harvest Rate (lb/24 hr)
Air‐Cooled Cube‐Type
2005 ARI Data
7.6
(7.75 – 7.6) / 7.75 = 2% Reduction
Technology + Energy Star +
California Energy Wise +
DOE 2005 Energy Policy Act
= More Efficient Machines.
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0
2
4
6
8
10
12
14
16
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0 500 1000 1500 2000 2500
Energy Consumption (kW
h/100 lb)
Ice Harvest Rate (lb/24 hr)
Air‐Cooled Cube‐Type
2012 AHRI Data
6.5
(7.6 – 6.5) / 7.6 = 14% Reduction
0
2
4
6
8
10
12
14
16
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0 500 1000 1500 2000 2500
Energy Consumption (kW
h/100 lb)
Ice Harvest Rate (lb/24 hr)
Air‐Cooled Cube‐Type
2012 AHRI Data – Increase Capacity
5.8
(7.6 – 5.8) / 7.6 = 24% Reduction
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0
2
4
6
8
10
12
14
16
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0 500 1000 1500 2000 2500
Energy Consumption (kW
h/100 lb)
Ice Harvest Rate (lb/24 hr)
Air‐Cooled Cube‐Type
2012 AHRI Data – Best In Class
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(7.6 – 5.0) / 7.6 = 34% Reduction
0
10
20
30
40
50
60
0 500 1000 1500 2000
Ice Harvest Rate (lb/d)
Wat
er C
onsu
mpt
ion
Rat
e (g
al/1
00 lb
)
.
All Air-Cooled Models
CEE Tier I Air-Cooled Models
2005 AHRI DatabaseObservation #3:
For a given capacity of air-cooled
machine, water use varies dramatically
18 to 38
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2014 AHRI Database
18 to 26
(38 – 26) / 38 = 32% Reduction
Energy and Water Wise:
We are headed in
the right direction!
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Perspective on
Water-Cooled Machines
Condenser cooling water dwarfs potable water use!
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750 gal = 500 lb
$2,900 a year!
quick condenser water calc
Big Lesson:
Specifying an
energy and water efficient
ice machine will save money
How Much?
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Our Restaurant has:
• 1 gas fryer
• 1 gas convection oven
• 1 solid-door reach-in refrigerator
• 1 gas griddle
• 1 700 LB ice machine
600 lb/day harvest
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1651 1964
556 820
2207 2784
How to Find Efficient Ice
Machines
and
Calculate the Savings
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Here’s where you find
efficient equipment
www.energystar.gov/cfs
www.fishnick.com
The F.S.T.C Modeling Method
1. Find the appliance energy information
2. Simulate the appliance energy usage
3. Transfer the info to a spreadsheet
4. Compare the efficient appliance to
the baseline appliance
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Find
http://www.ahridirectory.org/ahriDirectory/pages/home.aspx
AHRI Directory of Certified Product Performance
ACIM – Automatic Commercial Ice-Makers* and Ice Storage Bins
* Changed from “Ice-Cube Machines” to now include continuous-type machines.
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Simulate
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How to Calculate Savings?
Start at www.fishnick.com
www.fishnick.com/saveenergy/tools/calculators/
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Transfer
12345671234567
fryer 1 annual energy cost
baseline 100
actual design 75
dollar savings 25$
percent difference 25%
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Compare
fryer 1 annual energy cost
baseline 100
actual design 75
dollar savings 25$
percent difference 25%
fryer 2
baseline 100
actual design 70
dollar savings 30$
percent difference 30%
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Our Example Ice Machine
Decisions, Decisions...
1. base efficiency water cooled
2. base efficiency air cooled
3. high efficiency air cooled
4. high efficiency upsized air cooled
5. highest efficiency upsized air cooled
6. highest efficiency flake
30 Minute Break
Resume at 11:15
If you are not able to
attend Part Two:
Please fill out the
RFMA evaluation
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Part Two:
Load Shifting Ice Machines
www.fishnick.com/handouts/02182014
Download Today’s Handouts:
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But First...
Peak, Partial Peak, and Off Peak
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Energy (kWh) Prices Vary
Maximum Demand – Any time of Day
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Maximum Peak Demand – Noon to 6 PM
Maximum Part‐Peak Demand9 to Noon & 6 to 9 PM
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Demand (kW) represents how much
generation capacity the utility has
to reserve on your behalf
Summary: Ways You Pay
• Energy Charges (kWh)
– Peak
– Part-Peak
– Off Peak
• Demand Charges (kW)
– Max Demand
– Max Peak Demand
– Max Part-Peak Demand
(No Peak Demand in Winter)
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The Problem with Ice Machines
We run them when electricity is expensive.
They are off when electricity is cheap.
What is “Load Shifting” an Ice Machine
Running an ice machine off the utility-peak period,
and through the night to produce ice for the
next day.
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Potential Savings
1. Buying cheaper off-peak energy (kWh)
2. Reducing max and peak demand charges (kW)
Other Potential Benefits
1. Less heat in the kitchen (load on the AC)
2. More efficient operation (lower ambient)
3. Quieter kitchen (off during production)
Is this Possible...
Let’s Investigate
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Ice Machine Field Study #1
• How does the AHRI database relate to the real world?
• How much water (and energy) do they really use?
• How much ice do machines typically produce in different
types of operations (duty cycle)?
• What do typical load profiles look like?
www.fishnick.com/publications/appliancereports/special/Ice-cube_machine_field_study.pdf
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Ice Machine #1 - Typical Day Profile
0.0
0.5
1.0
1.5
2.0
2.5
3.0
6 AM 9 AM 12 PM 3 PM 6 PM 9 PM 12 AM 3 AM 6 AM
Po
wer
(kW
)
0
50
100
150
200
250
300
350
400
450
500
To
taliz
ed W
ater
(g
al)
Electric Water
Ice Machine Field Study
Avg. Duty Cycle = 48%Max. Duty Cycle = 61%Load Shift: YES
1060 lb/24 hr
Ice Machine #2 - Typical Day Profile
0.0
0.5
1.0
1.5
2.0
2.5
3.0
6 AM 9 AM 12 PM 3 PM 6 PM 9 PM 12 AM 3 AM 6 AM
Po
wer
(kW
)
0
50
100
150
200
250
300
350
400
450
500
To
taliz
ed W
ater
(g
al)
Electric 1 Electric 2 Water
Ice Machine Field Study
Avg. Duty Cycle = 50%Max. Duty Cycle = 65%Load Shift: YES
1130 lb/24 hr x 2
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Ice Machine Field Study
Avg. Duty Cycle = 60%Max. Duty Cycle = 91%Load Shift: Maybe
Ice Machine #3 - Typical Day Profile
0.0
0.5
1.0
1.5
2.0
2.5
3.0
6 AM 9 AM 12 PM 3 PM 6 PM 9 PM 12 AM 3 AM 6 AM
Po
wer
(kW
)
0
50
100
150
200
250
300
350
400
450
500
To
taliz
ed W
ater
(g
al)
Electricity Water
1130 lb/24 hr
Ice Machine #4 - Typical Day Profile
0.0
0.5
1.0
1.5
2.0
2.5
3.0
6 AM 9 AM 12 PM 3 PM 6 PM 9 PM 12 AM 3 AM 6 AM
Po
wer
(kW
)
0
50
100
150
200
250
300
350
400
450
500
To
taliz
ed W
ater
(g
al)
Electric Water
Ice Machine Field Study
Avg. Duty Cycle = 59%Max. Duty Cycle = 85%Load Shift: Maybe
340 lb/24 hr
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Ice Machine Field Study
Ice Machine #5 - Typical Day Profile
0.0
0.5
1.0
1.5
2.0
2.5
3.0
6 AM 9 AM 12 PM 3 PM 6 PM 9 PM 12 AM 3 AM 6 AM
Po
wer
(kW
)
0
50
100
150
200
250
300
350
400
450
500
To
taliz
ed W
ater
(g
al)
Electric Water
Avg. Duty Cycle = 83%Max. Duty Cycle = 100%Load Shift: No
275 lb/24 hr
Ice Machine #6 - Typical Day Profile
0.0
0.5
1.0
1.5
2.0
2.5
3.0
6 AM 9 AM 12 PM 3 PM 6 PM 9 PM 12 AM 3 AM 6 AM
Po
wer
(kW
)
0
50
100
150
200
250
300
350
400
450
500
To
taliz
ed W
ater
(g
al)
Electric Water
Ice Machine Field Study
Avg. Duty Cycle = 87%Max. Duty Cycle = 100%Load Shift: No
830 lb/24 hr
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Ice Machine Field Study
Ice Machine #7 - Typical Day Profile
0.0
0.5
1.0
1.5
2.0
2.5
3.0
6 AM 9 AM 12 PM 3 PM 6 PM 9 PM 12 AM 3 AM 6 AM
Po
wer
(kW
)
0
50
100
150
200
250
300
350
400
450
500
To
taliz
ed W
ater
(g
al)
Electric Water
Avg. Duty Cycle = 35%Max. Duty Cycle = 48%Load Shift: YES
440 lb/24 hr
Ice Machine Field Study
Ice Machine #8 - Typical Day Profile
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
6 AM 9 AM 12 PM 3 PM 6 PM 9 PM 12 AM 3 AM 6 AM
Po
wer
(kW
)
0
100
200
300
400
500
600
To
taliz
ed W
ater
(g
al)
Electric Water
1130 lb/24 hr
Avg. Duty Cycle = 35%Max. Duty Cycle = 78%Load Shift: Maybe
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Important Number:
A machine with a 60% to 65%
duty cycle is a good candidate for
load shifting
Load Shifting Example
• Full-service restaurant, open
for lunch and dinner.
• Two air-cooled ice machine heads
with remote condensers on top
of one bin.
• AHRI listed Ice Harvest Rate –
1,130(x2) lb/24hr
• AHRI listed 4.6 kWh/100lb
• Average Duty Cycle = 50%
• Peak Duty Cycle = 65%
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Daily Ice Machine Usage Profile
On-Peak Demand Period (Summer)
California Utility Rate Information• E-19 (Non-FTA Rates) Offers demand-metered time-of-use (TOU) service.
Customers likely to benefit have high electric use and high load factors and are able to use significant percentages of their electricity during the off-peak period. There are optional (E19V, E19 X and E19W) versions below 500 kW as well as E19 mandatory which applies to accounts with demands between 500 and 1,000 kW. See tariff for rate limiter, power factor, nonfirm.
• Meter charge: =$4.11992/day for E19 V or X; =$3.97799/day for E19W2/; =$13.55236/day for E19S mandatory; =$19.71253/day for E19P mandatory; =$39.42505/day for E19T mandatory
Summer
On Peak $13.17
Summer
On Peak $0.15463
Part Peak $3.02 Part Peak $0.10708
Maximum $7.97 Off Peak $0.08766
WinterPart Peak $1.15
WinterPart Peak $0.09577
Maximum $7.97 Off Peak $0.08480
Source: http://www.pge.com/tariffs/tm2/pdf/ELEC_SCHEDS_E‐19.pdf
Restaurants historically set their max peak during the on‐peak period for an effective demand charge of $21/kW on 5 kW > $100 per month.
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Energy Consumption SavingsSummer Season Normal Shifted Winter Season Normal Shifted
Days 183 183 Days 182 182
Power (kW) 4.83 4.83 Power (kW) 4.83 4.83
On‐Peak (hr/day) 6 0 On‐Peak (hr/day) N/A N/A
Part‐Peak (hr/day) 5.5 1 Part‐Peak (hr/day) 11.5 1.5
Off‐Peak (hr/day) 0.5 11 Off‐Peak (hr/day) 0.5 10.5
On‐Peak Cost $560 $0 On‐Peak Cost N/A N/A
Part‐Peak Cost $356 $97 Part‐Peak Cost $665 $87
Off‐Peak Cost $311 $840 Off‐Peak Cost $316 $828
Total Summer Costs $1,227 $937 Total Winter Costs $981 $915
Summer Cost Savings $290 Winter Cost Savings $66
Total Annual Costs $2,207 $1,852
Annual Cost Savings $355
Demand Charges SavingsSummer Season Normal Shifted Winter Season Normal Shifted
Days 183 183 Days 182 182
Power (kW) 4.83 4.83 Power (kW) 4.83 4.83
On‐Peak Charge $64 $0 On‐Peak Charge N/A N/A
Part‐Peak Charge $15 $15 Part‐Peak Charge $6 $6
Maximum‐Peak Charge $39 $0 Maximum‐Peak Charge $39 $0
Total Summer Costs $700 $90 Total Winter Costs $264 $36
Summer Cost Savings $610 Winter Cost Savings $228
Total Annual Cost $965 $126
Annual Cost Savings $839
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Savings Potential
• By moving the operation of the ice machine to mostly off-peak periods the energy cost savings would be $355.
• The Demand Charge savings would be an additional $839.
• Using a simple time clock to delay the operation of the ice machine this restaurant would see an annual savings of $1194.
38% Reduction in energy and demand charges
Important Note on Demand Savings:
If the max demand happens at some
time other than peak hours, you may
not get the full demand savings.
Without more detailed info: You can
only truly count on energy savings.
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What about savings from
upgrading the machines?
Potential Annual Energy Saving with High Efficiency Replacement Machine
0
2,0262,306
5,861
2,569
0
2,318
190
2,000
4,000
6,000
8,000
#1 #2 #3 #4 #5 #6 #7 #8
kWh
/yr
$0
$300
$600
$900
$1,200
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Potential Annual Water Saving with Low Water Use Rate Replacement Machine
50 44
5 0
256
2536
127
0
50
100
150
200
250
300
#1 #2 #3 #4 #5 #6 #7 #8
CC
F/y
r
$0
$250
$500
$750
$1,000
$1,250
$1,500
water-cooled
Ice Machine Field Study #2Energy and Water Saving
with Ice Machine Upgrade and Load Shifting
Food Service Technology Center
September 2011
fishnick.com/publications/fieldstudies/
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Average Cycle Power Reduction (kW) -- 0.16 Energy Saving (kWh/100 lb) -- 2.20 Energy Percentage Savin g -- 33.6% Annual Energy Saving (kWh) -- 1,580 Annual Energy Cost Saving -- $284 Water Saving (gal/100 lb) -- 4.0 Water Percentage Saving -- 13.8% Annual Water Saving (gal) -- 2,840 Annual Water Cost Saving -- $19 Annual Energy and Water Cost Saving -- $303 Peak Demand Reduction (kW) 8 -- 1.05
The Bottom Line
$500 total annual savings
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Ice Machine Field Study #3
Look for it on fishnick.com soon
True Burger, OaklandIce Machine – Calculated Energy Use
Old Ice Machine NewMachine
Rate Capacity (lb/24h) 155 410
Rated Energy Use(kWh/100 lb ice)
9.90 5.73
Duty Cycle (%) 86 29
Annual Energy Use Savings (kWh) ‐ 1,400
Demand Reduction (kW) ‐ 1.0
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39% Reduction in energy charges
TrueburgerCost Savings:
$264
50
Bridges Restaurant, Danville CA Ice Machine – Calculated Energy Use
Old Ice Machine NewMachine
Rate Capacity (lb/24 h) 751 1,180
Rated Energy Use(kWh/100 lb/ice)
6.6 4.62
Normalized Duty Cycle (%) 81 52
Annual Energy Savings (kWh) ‐ 4,986
On‐Peak Reduction (kW) ‐ 2.2
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Savings at Bridges:
New machine + upsizing + load shifting =
40% reduction in energy (kWh) costs
But, no demand (kW) charge savings
This is the safest formula for savings
at present
Ice Level at 12:00 PM
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Ice Level at 3:00 PM
Ice Level at 6:00 PM
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Important Note on Operations:
Empty the bin as early as possible in
the morning so the machine can
refill until noon
Important Note on Controls:
The best method to control the
machine is to hardwire the timer into
the bin switch.
That way if the ice cycle begins, the
machine does not turn off before harvest.
Then set the timer to cut off about
15 minutes before noon.
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How do you know if your ice
machine is a candidate?
55
Monitor the machine and
determine the duty cycle
56
Couple of final thoughts:
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Potential Issues with Upsizing?
• Space considerations?
• additional heat load to space if upsizing
without remote?
• existing breaker capacity?
Load Shifting Challenges?
• Ice storage bin is not large enough and ice
runs out during the day (or perceived to run
out)?
• possible complaint reaching ice on the
bottom of the bin?
• (First-in/first-out design is possible solution)
• Time clock failure defeats benefit
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The Future?
“In the foreseeable future, it is conceivable that ice making in all restaurants will be during non–peak utility periods, and in many cases, during the off-peak, cooler hours of the night.”
Don Fisher
Lunchtime!!
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FEBRUARY 16, 2014
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