Solar PV container for making ice for rural applications

1. Development of a concept for the
modular design and sizing of a PV ice-
making shipping container for rural
applications
by:
Ricardo Faerron Guzmán
In collaboration with:

2. Outline
1. Introduction to refrigeration in rural
environment
2. Commercial Ice-making Machine
3. Model for Prediction of Ice-making
with a PV power supply
4. Design of an Ice-making
Container
5. Results and Economic Analysis
6. Comparison of Systems
7. Limitations and Conclusions
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3. Introduction to Rural Refrigeration
Approximately over 1.4 billion people live without the benefits of electricity [1]
The basic element for the preservation and safe consumption of food
and storage of vaccines and other medicines is the use of refrigeration
Refrigeration can provide a means of income, when the increase yield of
food stuffs can be then sold to the market.
The project consisted of a technical solution for the production of ice through
a solar driven ice-making machine
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4. Income Generating Applications of Ice for Rural
Development
o The cold chain makes it possible to bring food products from far away and in
premium condition.
o The result of spoilage of food is financial loss and constrained economic and
social development.
o Increasing produce yield also leads to jobs for transport and distribution
o For the rural environment it has been recommended to have 2 kgice / kgfish and
0.5 kgice / kgmilk (per day)
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Fish sale at market [8]
Transportation of chilled
Milk [7]

5. Existing Case Studies
System in
Chihuahua,
Mexico [2]
-Fishing village
-Ice-maker
-2.4 kWp PV
-24Vdc 2200Ah
-About 75kg ice per
day
-1999 Cost of
approx.: $38,000
ISAAC System
[3]
-20 Systems in 7
countries
-125ft ^2 collector
-Ammonia absorption
cycle
-About 50kg ice per
sunny day
-Cost of approx.:
$17,000
Contained
Energy
System[4]
-Cold storage for fish
-10kWh VRLA
-6.4 kWp PV
-20m^3 storage
room
-500kg at -2°C
-Phase change
material
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6. The ILK Ice-making Prototype
6
[5]

7. The ILK Ice-making Prototype
o 5.1 kWp PV with estimated 300 kg of ice produced under 6.5
kWh/m2/day
o Variable frequency drive of the refrigeration compressor allows
it to work during the day
o Ice-making machine, electronic and control system are made
in-house by ILK
o Containers are intended to be custom made to costumer
specifications
o Cost estimates are in the range of €100,000
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8. Why search for a new approach?
o Design process can be a lengthy one for a customized solution
o The cost of such a customized system presents a great barrier
for their sales
o There is no available comparison of the ILK system with market
available ice-makers
o A standard product can provide the potential user with a system
with known performance and characteristics
o Cost reduction through modular design possibilities:
o Use market available electronics (inverter, charger, batteries)
o Use commercially available ice-making machine
o Minimize machining needed to modify container
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9. Commercial Ice-making Machines
o The Consortium for Energy Efficiency
(CEE) list of high efficient ice machines
was analyzed
o Findings:
o In general smaller machines are less
efficient
o The energy efficiency does not make
a correction for ice hardness
o Flake ice contains part of its mass as
water (30%), so does nugget ice
(20%)
o Water consumption is also an issue
to consider
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[6]
[6]

10. Coefficient Of Performance (COP) of Ice-machines
Machine
Model
Compressor
Type of
ice
Temps of
COP
calculation
Ice
Production*
Energy
Use*
Average
power
Cooling
Energy
to
-5°C **
Calculated
overall
COP **
Hoshizaki
Tair / Twater
(°F/°F)
(lbs/
24 hrs)
(kWh/
100lb)
(kW) (kW)
F-801MAH Joint Flake ice
70/50 823 3.20 1.097 1.207 1.100
90/70 599 4.50 1.123 1.037 0.923
F-801MAH-
C Joint Cubelet
70/50 752 3.50 1.097 1.239 1.130
90/70 552 5.10 1.173 1.055 0.900
KM-
515MAH Joint Crescent
70/50 501 4.70 0.981 1.007 1.027
90/70 435 6.00 1.088 0.989 0.910
KM-
650MAH Joint Crescent
70/50 589 4.50 1.104 1.184 1.072
90/70 512 5.80 1.237 1.165 0.941
KM-
901MAH Joint Crescent
70/50 874 4.40 1.602 1.757 1.097
90/70 732 5.60 1.708 1.665 0.975
KM-
1340MAH Joint Crescent
70/50 1325 3.80 2.098 2.664 1.270
90/70 1167 4.70 2.285 2.654 1.161
KM-
1601SAH Joint Crescent
70/50 1462 4.03 2.455 2.939 1.197
90/70 1343 4.70 2.630 3.055 1.161
* Not corrected for ice hardness
* * Corrected for ice hardness
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11. Daily Model for Ice-making
Output Ice
Battery
bank
η = 63%
PV Modules
PR = 70%
ηpv_module = 13.7% @ STC
PV Area
Inverter
η = 94%
MPPT
Charger
η = 96%
Solar Radiation
Air Temperature
Water Temperature
Hourly
simulation
for one day
Loads
11
[6]
Water pump
Lights
Ice-making machine

12. Results
• Seven Machines where modeled
• Simulation was run for meteorological data for 4 typical days in Durban, S.A.
Procedure
1. First, the ideal situation where all energy provided by the battery was restored by
the PV modules was analyzed
2. This leads to different hours of operation for each of the 4 different days
3. The minimum hours of operation was taken
4. These minimum number of hours were then fixed for all 4 days simulated
* Corrected for ice hardness
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Ice Production ( corrected for ice hardness) [kg]
Machine
Model
Type of
ice
Hours of
operation
4.6
kWh/m^2
/day
@ 15.3°C
Avg *
5.6
kWh/m^2
/day
@ 22.9°C
Avg *
4.9
kWh/m^2
/day
@ 14.2°C
Avg *
5.0
kWh/m^2
/day
@ 26.4°C
Avg *
Average
*
KM-515-MAH Crescent 8.6 81.6 74.2 82.5 71.0 77.4
KM-650-MAH Crescent 7.7 85.7 78.0 86.6 74.8 81.3
KM-901-MAH Crescent 5.3 88.1 77.8 89.3 75.5 82.7
KM-1340-MAH Crescent 3.3 85.5 77.5 85.9 75.3 80.6
KM-1601-SAH Crescent 2.8 80.8 76.0 80.7 73.2 77.7
F-801-MAH Flake 8.41 95.2 77.0 98.1 72.1 85.6
F-801-MAH-C Cubelet 8.15 97.4 78.3 100.3 72.9 87.2
Daily Ice Production Prediction

13. Container Design
o Once the selection of a machine has been made, then the rest of the
system can be designed, and costs estimations made
13
Electronic
Component Design
Sub-systems in the
container design

14. Economic Analysis
Day
Solar
irradiation
Average
temperature
Predicted
possible ice
production
Days
Totals
(kWh/
m^2/day) (°C) (kg) (kg)
37 5.6 22.9 78.3 Jan-March 90 7,047
168 4.6 15.3 97.4 April-June 91 8,863
185 4.9 14.2 100.3 July-September 92 9,228
350 5.0 26.4 72.9 October-December 92 6,707
Year Total 31,845
Availability 85%
20 year total 541,362
14
Yearly Ice Production Prediction

15. Comparison of Systems
o An fair comparison is difficult. No standard testing conditions
(different irradiations, air and water temperatures, ice
hardness)
o Under the different test conditions ILK seems to still present
the system with highest ice production and lowest lifetime
cost of ice
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Preliminary Comparison

16. Limitations of study
 Control System: fixed amount of hours through a day
 Other costs: water supply and shipping
 Daily model vs. Yearly simulation
 Non-technical and financial aspects
 Funding
 Training
 Technical Support
 Maintenance
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17. Conclusions
 COP of analyzed ice-machines are in the range of 1
 Largest cost for Investment and NPV is that of the ex-
works (62% and 40.3% respectively)
 ILK system is more efficient and produces ice at a lower
cost but, by assembling onsite, the proposed system can
close this gap
 System would also benefit from an organization
dedicated to providing funding, training, supervision and
maintenance for systems for rural applications
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18. Thank you for your attention
Question?
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19. Bibliography
1. The World Bank. Worldbank.org. Energy - The Facts. [Online] 2011. [Cited: 02 01 2013.]
http://web.worldbank.org/WBSITE/EXTERNAL/TOPICS/EXTENERGY2/0,,contentMDK:22855502~pagePK:210
058~piPK:210062~theSitePK:4114200,00.html.
2. Rudischer, R.; Waschull, J.; Leupolt, H.; Prastka, F. Abschlussbericht Produktenwicklung PV-Eirerzeuger.
Dresden : ILK-AB-32/05-247, 2005. Internal document.
3. Estrada, L.; Foster, R.; Cota, A.D. .First Year Performance of the Chorreras PV-Hybrid Ice making System in
Chihuahua, Mexico. Mexico : ISES Forum, 2000. DSA 09-03.
4. Ericson, C. Rural Milk Collection Centers ISAAC Solar Icemaker. Nairobi, Kenya : s.n., 24 May 2005. East and
Southern African Dairy Association Conference.
http://www.dairyafrica.com/html/conferences/pdf/conf01_presentations/Session%208/Carl%20Erickson%20-
%20Rural%20Milk%20Collection%20Centers.pdf.
5. Contained Energy. Containedenergy.com. Contained Energy Solar Powered Cold Storage Systems. [Online]
2012. http://www.containedenergy.com/CE_Solar_Powered_Cold_Storage_System_1.01.pdf.
6. Hoshizaki America. Hoshizakiamerica.com. F-801M_H-C Modular Cubelet Ice Machine. [Online] [Cited:
02.01.2013] http://www.hoshizakiamerica.com/color-specs/F801MHC.pdf.
7. ISAAC Solar ICE Maker. http://solaricemaker.com/. Phtograph of website from: Solar Ice Company, Annapolis,
Maryland. [Online] [Cited: 31.01.2016] http://solaricemaker.com/
8. Fish Consulting Group. http://fishconsult.org/ Photograph from article: Marketing and consumer preference in
Lao PDR [Online] [Cited: 31.01.2016] http://fishconsult.org/?p=12635
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20. Special Thanks
Russom Semere
Dirk Gutzeit
Tobias Zwirner
Hans Holtorf
Daniela Vega
Dr. Jörg Waschull
Wolfgang Hernschier
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