SOLAR ENERGY FOR COOKING AT CENTER FOR COMMUNITY YOUTH
SUPPORT
Prepared by Sydney Kambalikena
10 October 2021
1
INTRODUCTION
Project background
Center for Community Youth Support (CCYS) is a community-based organization located in the out
skirt of Lilongwe city, Malawi. The organization has been implementing a number of community
development initiatives since 2012. Fore among the community development initiatives is the feeding
program, which caters for 380 pupils and 48 secondary school female students proving them with
breakfast, lunch and supper. The program has been instrumental in motivating students to remain in
school. Despite many other expenditures associated with the program, one of the biggest expenses
associated with the program is purchasing firewood for cooking. The Malawi government has been
discouraging people from using firewood for cooking to reduce deforestation and global warming
which has greatly affected the country. CCYS made a request with electricity supply corporation of
Malawi (ESCOM) to get electricity, but that request has remained unattended to for the past six years
now. As things stand, exploring other options to get energy for cooking is the best way forward.
Location
CCYS is located in Area 25 Lilongwe, Malawi. The catchment area covers five villages namely; Tsale,
Pheleni, Mzumanzi 1, Mzumanzi 2, and Galeta. Below is the satellite image of the site.
PROJECT MAIN OBJECTIVE
The project main objective is to come up with the solar system which will provide power for cooking.
2
Specific Objectives



To come up with a solar system size to provide power for cooking
Select the type and size of electric pots to be used for cooking
Layout drawing for the system setup
METHODOLOGY
General methodology
A visit was made to CCYS to obtain the basic data which will be used to design the system. The
following basic data were obtained during the visit;



Number of pupils/ students fed with porridge, lunch and supper
Size of pots used for cooking
Time and period for preparing food
Selection of electric pots
Based on the assessment two 60-liters electric pots were selected to be used for cooking of 12kw each
3 phase.
LOAD POWER ANALYSIS FOR THE SYSTEM
Food
# of
people
fed
Breakfast
385
(Porridge)
Lunch
Supper
48
48
Size of pot
used
Coking
period
Times
(hrs.)
Pot
wattage
1.5
12000
0.8
14400
9am-10:30am
1.5
12000
0.5
9000
(9am-10am)
1
12000
0.5
6000
3pm-4:30pm
1.5
12000
0.5
9000
3pm-4pm
1
12000
0.5
6000
1
18
1
108
60L pot (1pot) 7am-9am
40L
pot
(Nsima/ rice)
20L
pot
(relish)
40L
pot
(Nsima/relish)
20
liters
(relish)
Loading
factor
Used power
(Kwh)
Additional
loads
Indoor
9
lights
2
Security
9
lights
12
Total
required
power
The total daily energy requirement to power the loads per day 44536wh
3
44526
BATTERY STORAGE
Considerations
The PV plant will provide all the power for cooking considering that all the cooking activities will be
done during the day when there is the sun, but in case of times when there is low power output from
solar system then, the battery will support the solar panels. The battery will be designed to provide
half of the required power to support the solar panels during low power output.
Daily energy requirement= 44526wh
Designed daily battery capacity=44526wh/2=22263wh
Days of autonomy=1
Depth of discharge (DoD)=80%
DC input battery input=48V dc
Required battery capacity= (daily energy requirement ×days of autonomy)/ (system voltage× DoD)
=22263h ×1) / (48×0.8)
= 579Ah @48v DC
Option
Battery
type
Battery
life span
1
Lead
acid
GEL
Lithium
ion
3 years
Battery
system
capacity
579ah
10 years
579ah
2
Battery
capacity
System
voltage
200ah @ 48v DC
12v
200ah
@48v
48v DC
Number
of
batteries
12
Unit cost
(U$)
Total cost
(U$)
365.86
4,390.32
3
3,048.78
9,146.34
INVERTER
The inverter size is determined by adding the AC loads and then multiply with safety factor.
Inverter capacity=daily load demand (w) ×safety factor
= ({0.8 x 12000+0.5 X 12000} ×1.25
=19500w
Therefore, 30kva inverter capacity is selected to power the AC loads.
4
PV ARRAY CAPACITY
Considerations
Required dairy energy demand: 44526wh
Selected PV module:300w, 36V,8.3A; Isc =8.9, VOC =44.
Selected PV input voltage :350v DC
Design sunshine hours for Lilongwe:6 hours per day
Battery voltage: 48V
PV capacity= Dairy energy demand / (sun shine hours ×de-rating factors)
=44526w/ (6h×0.8)
=9276.25w
Number of Panels in series Nps=350v/36v
=10
Number of series strings Npp
=9276.25/ (10 ×300)
=3
Total number of panels = Nps × Npp =3×10
=30 panels
Adjusted system capacity for the system =30×300w=9kw
CHARGE CONTROLLER
Considerations
Selected PV module:200w, 30V,8.2A; Isc =8.9, VOC =44.
Model: GTE -300W-P-72-(Vmp=36V)
Type: Monocrystalline
Charge controller size=Number of modules in parallel × Isc × safety factor
=3×8.9×1.25
=34A
5
SYSTEM SUMMARY
The proposed system design consists of the following details:
SOLAR PV SYSTEM
Components
Description
Solar Panels
Lithium-Ion Batteries
Inverter
Combiner box
Battery isolator
PV structure
Cables
and
accessories
Total
6
other
300w
–
Monocrystalline
200AH @48V DC
30kva
Fused, surge and
isolator type
QTY Unit price (U$)
Total Price
(U$)
30
6600
3
1
220
3659
9756.1
2
243
486
metal type
2
1
121
609.8
242
609.8
bunch
1
621
621
10977
9756.1
29291.9
SCHEMATIC LAYOUT DIAGRAM OF THE SYSTEM
PV Array
DC Bus
Inverter
Battery
Bank
Pot 1
Kitchen layout
5m
2m
6.5m
Power Room
veranda
7
4m
Pot
1
2m
Pot
2
Pot 2
Site for Extension 6.5 meters by 11meters
8