The document details a case study on the use of ammonia hot water heat pumps by Mayekawa Australia Pty Ltd, highlighting their advantages as natural refrigerants with zero ozone depletion and global warming potential. It outlines the energy savings achieved in a small goods production facility by utilizing waste heat, leading to significant reductions in energy consumption and costs. The implemented system demonstrated a return on investment (ROI) of less than three years, surpassing initial projected savings.

2. Ammonia Hot Water Heat
Pump Case Study
Mayekawa Australia Pty Ltd

3. Climate Change
• Availability ?
• High Price - >$100/kg
• Readily Available
• Price - <$10/kg

4. • Ammonia has no ozone depletion potential (ODP = 0)
• Ammonia has no global warming potential (GWP=0)
• A pure “Natural Refrigerant”
• Used widely and safely around the world in large-scale
industrial cooling systems. Applications include food
processing, petro chemical, process cooling and air
conditioning. For many years.
• Excellent Thermodynamic Properties - High COP

5. Ammonia NH3
Refrigerant
ODP: Ozone Depletion Potential
GWP: Global Warming Potential ODP
GWP
[100yrs]
Safety
classification
Natural
Refrigerants
CO2 (R744） 0 1 A1
Ammonia (R717） 0 0 B2
Propane (R290) 0 3 A3
Iso-Butane
(R600a) 0 3 A3

6. Utilising Waste Heat :
THR = kWr + kW abs
1009.3kWr + 246.5kW abs
1.26 MW
MODEL : N220JL-V
REFRIGERANT : AMMONIA
RECOMMENDED PORT : M
BOOSTER : N
Vi : [-] 3.23
COMPRESSION RATIO : [-] 4.65
CAPACITY : [kW] 1009.3
ABSORBED POWER : [kW] 246.5
Typical IP Compressor @ Te/Tc -10°C / +35°C

7. Solution :
Ammonia Heat Pumps

8. Project Outline: Small Goods Production Facility
1. The facility consumes a significant quantity of hot water daily, primarily
generated by LPG fired steam boilers.
2. 65°C hot water used primarily for wash down & boiler make up.
3. The refrigeration plant utilises a desuperheater, however higher grade
heat is required from this loop for factory services.
4. Hot water generation uses a high % of the total site energy.
5. Significant heat of rejection from the refrigeration system, so
utilisation of this “waste heat source” seen as a key factor for reducing
overall plant energy consumption.

9. Refrigeration Total Heat Rejection
SINGLE STAGE SCREW COMPRESSOR : 2019_ver.1
MODEL : N250VS*-M
REFRIGERANT : AMMONIA
RECOMMENDED PORT : L
Vi : [-] 2.98
COMPRESSION RATIO : [-] 4.65
CAPACITY : [kW] 1393.3
ABSORBED POWER : [kW] 330.6
SINGLE STAGE SCREW COMPRESSOR : 2019_ver.1
MODEL : N200VM*-M
REFRIGERANT : AMMONIA
RECOMMENDED PORT : L
Vi : [-] 3.23
COMPRESSION RATIO : [-] 4.65
CAPACITY : [kW] 824.9
ABSORBED POWER : [kW] 207.2
N200VMD
N250VSD
N160VLD LT = 334kW
Total: = 3,089kW
MT = 2,755kW

10. Heat Pump Design Data
REFRIGERANT AMMONIA
MODEL N6HK
BOOSTER N
CAPACITY [kW] 462.0
ABSORBED POWER [kW] 75.8
SPEED [min-1] 1450
LOAD [%] 100
CONDENSING TEMP. [degC] 70.0
EVAPORATIVE TEMP. [degC] 30.0
SUCTION SUPERHEAT [degC] 1.00
LIQUID SUBCOOLING [degC] 40.0
SUCTION PRES. [MPaA] 1.17
DISCHARGE PRES. [MPaA] 3.31
SWEPT VOLUME [m3/h] 193
DISCHARGE TEMP. [degC] 118
COP [-] 6.09
HEATING CAPACITY [kW] 532.0
COPh [-] 7.02
COPt [-] 13.1

11. The Over Compression
Heat Pump Cycle
Heat Recovery Tank
Desuperheater
Refrigeration System
High Temperature
Heat Pump
Subcooler
Condenser
CW Inlet
13°C
Existing Hot Tank
To Process
35°C
65°C
65°C
65°C
Existing Hot Tank
Boiler Make Up

12. Energy Savings :
Measured Heat Pump Data
• Heat Pump Absorbed (Power & kWh)
• Water Flow Rate (lpm)
• Outlet Water Temperature (°C)
• Operational Hours
Operating Characteristics
HP Input 84 kW abs
Flow Rate 3.6 l/s
Temp in 13°C
Temp out 61°C
HP Output 723 kWt
Total COP 8.4
The Heat Pump operates in an on/off cycle subject to process demand.
The run time is approximately 2,300 hours / year.

13. Daily Average Values
Flow Temp HP Input HP Input HP Output HP Output Fuel Offset
lpm °C kWe kWhe kWt kWht kWh lpg
2/01/2019 Off
3/01/2019 Off
4/01/2019 34 59 11 275 138 3,314 3,898
5/01/2019 49 59 17 404 204 4,889 5,752
6/01/2019 57 59 19 466 232 5,578 6,563
7/01/2019 54 59 19 447 221 5,298 6,233
8/01/2019 60 58 20 489 242 5,810 6,835
9/01/2019 61 59 21 500 252 6,040 7,106
10/01/2019 Off
11/01/2019 Off
12/01/2019 57 58 19 467 230 5,518 6,492
13/01/2019 69 59 24 569 283 6,785 7,982
14/01/2019 54 41 19 459 154 3,703 4,357
15/01/2019 47 36 17 398 118 2,836 3,336
Avg Day 54 55 19 447 207 4,977 5,855
Avg Week 54 55 19 2,237 207 24,886 29,277
Avg Year 54 55 19 116,340 207 1,294,046 1,522,407
Net Savings 1,406,000 kWh
Electricity Rate $0.15kWh
LPG Rate $0.11kWh
Savings $166,100.00
Additional Cost $18,000.00
Net Savings
$148,100.00

14. 0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
EfficiencykWh/kg
Date
Production Efficiency
0.77kWh/kg
0.67kWh/kg
Post Installation Average
Pre Installation Average

15. Results:
Annual
Consumption
Reduction
Annual Energy Cost
Reduction
Cost of Implementation
inc En Gr Payback Period
1,459,000 kWh $147,900.00 $370,000.00 2.7 years

16. Summary:
• Significant energy savings were observed at implementation.
• Projected savings for the project were 1,173,000kWh.
• Actual savings were 1,407,000kWh well above projected figures.
• ROI less than 3 years making the project viable.

17. Ammonia Chillers
- Low Charge –
• Air Conditioning - Building Services / Process
• Process Cooling - Water / Glycol
• Cold Storage - Secondary Refrigerants

18. Ammonia
Chillers
2x 200kW
Te/Tc 0/35°C
Capacity 400kW

19. Ammonia
Chillers
Capacity 835kW
Te/Tc 0/35°C
Ammonia Charge:
160kg

20. Capacity 3.6MW
Te/Tc 0/35°C
Ammonia Charge:
600 kg
Ammonia
Chillers

21. Ammonia / CO2
Cascade
Te / Tc -45/-10/+30°C
Capacity: 247kW

22. Natural Refrigerants
The only way forward !