Rooftop Solar
Industrial Installations
Embedded Generation
Line Diagram of Solar PV system for Ceres Fruit Growers
CB
To Factory
Sub DB
L1
PE
N
PE
Customer's earth terminal
CB
Meter 2
Meter 1
CB
Key:
CB circuit-breaker
DB distribution board
EG embedded generator
E/L earth leakage
EG1
Meter 3
N
PE
EG2
Meter XX
N
L1
L2
L3
E/L
L1
L2
L3
CB
L1
L2
L3
PE conductor
Main Supply
Main DB
Customer side
Supply Source
transformer
L2 L3 N
EGXX
E/L
E/L
CB
CB
Solar DB
Note 1 : Meters 2 to XX are integrated in the Inverters
Statistics
• 1700 kWh per year for every 1kW of solar.
– Eg 1MW solar plant = 1700MWh per year.
March
Feb
Jan
1200.00
1200.00
1000.00
1000.00
800.00
800.00
600.00
600.00
400.00
400.00
400.00
200.00
200.00
200.00
1200.00
1000.00
800.00
600.00
0.00
0.00
1
1
April
0.00
MAY
June
1200.00
1200.00
1200.00
1000.00
1000.00
1000.00
800.00
800.00
800.00
600.00
600.00
600.00
400.00
400.00
400.00
200.00
200.00
200.00
0.00
0.00
0.00
Load profile kWh
Load Profile kWh
Solar generation kWh
900 000
800 000
700 000
kWh
600 000
500 000
400 000
300 000
200 000
100 000
Jan
Feb
Mrch
April
May
June
July
Aug
Sept
Oct
Nov
Dec
July Load profile
Load no solar
2000
1500
kW
1000
500
0
-500
-1000
Load with Solar
August Load profile
Load no Solar
2000
1500
kW
1000
500
0
-500
-1000
Load with Solar
Sept Load profile
Load no Solar
2000
1500
kW
1000
500
0
-500
-1000
Load with Solar
October Load Profile
Load no Solar
2000
1500
kW
1000
500
0
-500
-1000
Load with Solar
November Load profile
Load no Solar
2000
1500
kW
1000
500
0
-500
-1000
Load with Solar
January Load profile
Load No Solar
2000
1500
kW
1000
500
0
-500
-1000
-1500
Load With Solar
Cost to Municipality
•Typically R330 000 per year loss of income per 1MW installation
•Ceres Fruit Growers for instance 1MW Solar
•
Total Electricity account R23 300 000 pa
•
Loss of surplus to municipality R330 000 pa, 1.3% of account
•
Expected growth in demand per year 6-8%
•1 Solar Water Geyser saves120 kWh per month or 1460 kWh per year
•1MW Solar panels = 1700 000 kWh per year = 1180 Solar water Geysers
•Replacing 1x60W bulb with a 5 Watt LED for 6 h per day saves 120 kWh per year.
•If the average household replaces 10x 60W bulbs with 10x5W LEDs then the
saving = 1200 kWh per year.
•Thus a 1MW solar installation = 1411 households changing 10 bulbs to LED