2. Danfoss
  3. Save Energy in your Supermarket

Danfoss Save Energy in your Supermarket User guide

  • Hello! I am an AI chatbot trained to assist you with the Danfoss Save Energy in your Supermarket User guide. I’ve already reviewed the document and can help you find the information you need or explain it in simple terms. Just ask your questions, and providing more details will help me assist you more effectively!
Save Energy in your Supermarket
with a CO
2
Refrigeration system
Benchmarking energy optimised HFC stores
with transcritical CO
2
booster systems
White Paper
ADAP-KOOL® Refrigeration control systems
Energy consumption Fakta
0
2000
4000
6000
8000
10000
12000
mar-10 maj-10 jun-10 aug-10 sep-10 nov-10 jan-11 feb-11 apr-11 jun-11
Time
KWh/month
0
2
4
6
8
10
12
14
16
18
Ambient temperature [C]
HCF (ref)
Trans 1
Trans 2
Average temperature [
℃
]
The Danish Supermarket Chain, Fakta – owned by
Coop Denmark has experienced signicant energy
savings with their second generation transcritical
booster system.
Fakta saves 10% energy by applying a CO
2
system
compared to HFC systems.
2 White paper RA8AC202 © Danfoss 10/2011 C0
2
-Transcritical booster system
Fakta has continuously worked on lowering their
energy consumption for the past 15 years, rst
on their HFC scroll packs and later on transcritical
packs. As a result of this Fakta are now installing
their second generation transcritical packs where
part load has been optimized. Fakta and the
remote monitoring centre AK Centralen has been
collecting data from the systems for more than
15 years, where they started optimizing the HFC
pack with low energy consumption and tempera-
ture quality as main targets.
Fakta The Fakta chain has 378 stores in operation
where 61 of them are transcritical. Fakta was one
of the rst movers to change to CO
2
and the rst
generation of transcritical systems were installed
in 2007. The aim for 2011 is to install more than
40 systems which are relatively small with 9 kW
on LT and 28 kW on MT.
Today all systems are produced in batches of 5
packs as they are standardised with the same
conguration regarding capacity. The installation
can be dierent but cabinets, pack and gascooler,
are always the same arrangement. This makes
Fakta a very good reference for energy studies.
System design:
HFC system
• Parallel R404a system with very good load
adaptation
• Controlled by ADAP-KOOL® pack controller
and AKC 114A case controllers with electronic
expansion valve type AKV
• 148 systems in operation
• 10 selected for the study.
Transcritical 1st generation system
• Booster system with gas by pass.
• 2 compressors for MT (33/67%) and 2 for LT
(33/67%
• Mechanical gas by pass valve
• Controlled by ADAP-KOOL® pack controller,
EKC 326 controlling ICMTS high pressure valve,
and AK-CC 750 case controllers with electronic
expansion valve type AKV
• 32 systems in operation
• First10 selected for the study.
Transcritical 2nd generation system
• Booster system with gas by pass
• 2 compressors, one with AKD inverter for MT
and 2 compressors without inverter for LT
• Controlled by ADAP-KOOL® pack controller,
EKC 326A controlling ICMTS high pressure
valve and CCM stepper gas by pass valve, and
AK-CC 750 case controllers with electronic
expansion valve type AKV
• 10 systems in operation May 2010 and 29 in
December 2010
• First 10 selected for the study.
HP High Pressure
HP Receiver Pressure
LP Suction Pre
ssure MT
LP Suction Pressure LT
Danfos
s
R64-2062.10
AKV
AKV
ICMTS
CCM
Danfos
s
R64-2063.10
AKV
AKV
ICMTS
Danfos
s
R64-2061.10
AKV
AKV
C0
2
-Transcritical booster system White Paper RA8AC202 © Danfoss 10/2011 3
Energy consumption Fakta
Time
KWh/month
Ambient temperature [C]
HCF (ref)
Trans 1
Trans 2
Average temperature [
℃
]
Selection criteria for energy
study
For the installation to be included in the data
material the following criteria had to be fullled:
• More than 4 months of operation since commis-
sioning
• Equivalent size and opening hours
10 installations have been selected from each
system. The stores are identical on most parame-
ters, but the installation will of course be dierent
regarding length of pipes and number of bends.
The maximum pressure drop in the pipe work is
still the same for all systems regardless of refriger-
ant and installation.
Results
The energy data in this study is collected from
May 2010 to April 2011. The plot shows energy
consumption per month for the 3 dierent sys-
tems (HFC, Trans 1 and Trans 2) and the average
ambient temperature for the month.
Application Engineer Kenneth B. Madsen from
Danfoss explains “Our measurements indicates
approximately 10% energy savings in Denmark
when comparing the 2nd generation transcriti-
cal CO
2
system with the HFC system - with the
lowest energy consumption in the cold months”
and further “The results also show a technology
improvement since 2007 where the rst genera-
tion transcritical system was installed.
Conclusion
The results show that the 2nd generation tran-
scritical systems in Fakta consume approximately
10% less energy than the HFC packs installed
until 2007. Energy simulations indicate that the
energy consumption in Denmark should be ap-
prox 10% lower than HFC systems which are very
much in line with the test results.
The dierence in energy consumption between
the 1st and 2nd generation CO
2
transcritical
systems can be explained by improved part load
capabilities and smooth control of gas bypass as
well as availability of components in smaller sizes
to be able to better match the capacity also for
smaller systems.
And a new CO
2
injection algorithm in AK-CC 750.
4 White paper RA8AC202 © Danfoss 10/2011 C0
2
-Transcritical booster system
FC-SPMC
Danfoss can accept no responsibility for possible errors in catalogues, brochures and other printed material. Danfoss reserves the right to alter its products without notice. This also applies to products
already on order provided that such alternations can be made without subsequential changes being necessary in specications already agreed.
All trademarks in this material are property of the respecitve companies. Danfoss and Danfoss logotype are trademarks of Danfoss A/S. All rights reserved.
/