This presentation explains an example of Standalone Solar PV system design for a household.

1. Stand alone Solar PV System
design
Solar PV design Modules: Design of 1KW stand alone SPV system: Calculation of Load,
Size of battery bank, Array Size, Distance between Modules in Array formation,
Costing, Grid Interactive PV System: Export of PV power to grid, Grid Interactive
Inverter, Islanding, reverse power flow, Surge protection, Wire sizes and voltage
ratings, AC modules
31-08-2016 IEC-803 ENERGY BASICS BY DR N R KIDWAI, INTEGRAL UNIVERSITY 1

2. Stand Alone PV System Design
A. Load Estimation
31-08-2016 IEC-803 ENERGY BASICS BY DR N R KIDWAI, INTEGRAL UNIVERSITY 2
A1 Inverter Efficiency 90% A2 Battery Bias Voltage 12 V Inverter AC Voltage 220 V
Appliances
Rating
(Watt)
Qty
Net Rated
Wattage
Adjustment factor
For dc 1, For ac A1
Adjusted
Wattage
Uses in Hours /day
Energy
/day (Wh)
A4 A5 A6 = A4/A5 A7 A8=A6*A7
LED Bulb 7 5 35 0.9 38.9 4 155.6
Fans 70 3 210 0.9 233.3 8 1866.4
LED TV 60 1 60 0.9 66.7 8 533.6
refrigerator 45 1 45 0.9 50 8 400
Washing machine 500 1 500 0.9 555.6 0.5 277.8
Laptop 50 1 50 0.9 55.6 2 111.2
A11 Total AC power req. 890 W A12 Total DC power req.989 W A9 Total Energy demand
per day
3244.6
Wh
A10 Total amp-hour demand per day (A9/A2) 270.4 Ah

3. Stand Alone PV System Design
B. Battery Sizing
31-08-2016 IEC-803 ENERGY BASICS BY DR N R KIDWAI, INTEGRAL UNIVERSITY 3
Location Lucknow Lattitude 26.80 N Design temperature 25 degrees C / 77 degrees F
B1 Days of storage desired / required (autonomy) 3
B2 Allowable Depth of Discharge (DoD) limit 0.8
B3 Required battery Capacity (A10 x B1/B2) 1014 Ah
B4 capacity of selected 12 V battery ( Exide FIP0-IP150..(150Ah) Price 10100) 150 Ah
B5 Number of batteries in parallel (B3 / B4) 7
B6 Total battery amp-hour capacity (B5xB4) 1050 Ah
B7 Total battery kilowatt-hour capacity (B6xA2/1000) 12.6 KWh
B10 Average daily depth of discharge (.75xA10/B6) .19

4. Stand Alone PV System Design
C. PV Array Sizing
31-08-2016 IEC-803 ENERGY BASICS BY DR N R KIDWAI, INTEGRAL UNIVERSITY 4
Design Tilt Lucknow (Latitude+100) 36.80 Design month: February
C1 Total energy demand per day (A9) 3244.6 Wh
C2 Battery round trip efficiency (0.70-0.85) 0.85
C3 Required array output per day (C1 / C2) 3817.2 Wh
C4 Selected PV module max power voltage at STC (18x0.85) 15.3 V
C5 Selected PV module guaranteed power output at STC 100 W
C6 Peek sum hours at design tilt for design month 4.63 hours (Av PSH Lucknow =5.3 h)
C7 Energy output per module per day (C5xC6) 463 Wh 530 Wh
C8 Module output at operating temperature (DFxC7) 324.1 Wh 424 Wh
DF=0.80 for hot climates. DF=0.90 for moderate climates
C9 Number of modules req. to meet energy req. (C3 / C8) 12 modules 10 modules
C13 Nominal rated PV module output 1200 W 1000 W
MODEL: GS-STAR-100W

5. Stand Alone PV System Design
D. Balance of Systems
31-08-2016 IEC-803 ENERGY BASICS BY DR N R KIDWAI, INTEGRAL UNIVERSITY 5
A voltage regulator (Charge Controller) is recommended unless array output current (at 1000 W/m2
conditions), less any continuous load current, is less than 5 % of the selected battery bank capacity (at
the 8 hour discharge rate0).
Wiring should be adequate to ensure that losses are less than 1% of the energy produced.
In low voltage (i.e., less than 50 volts) systems, germanium or Schottky blocking diodes are preferred
over silicon diodes.
Fuses, fuse holders, switches, and other components should be selected to satisfy both voltage and
current requirements.
All battery series branches should contain fuses.
Fused disconnects are strongly recommended to isolate the battery bank from the rest of the system.
Refer to electrical and mechanical design sections for other considerations.

6. Grid Connected Rooftop PV System Design
31-08-2016 IEC-803 ENERGY BASICS BY DR N R KIDWAI, INTEGRAL UNIVERSITY 6
A voltage regulator (Charge Controller) is recommended unless array output current (at 1000 W/m2
conditions), less any continuous load current, is less than 5 % of the selected battery bank capacity (at
the 8 hour discharge rate0).
Wiring should be adequate to ensure that losses are less than 1% of the energy produced.
In low voltage (i.e., less than 50 volts) systems, germanium or Schottky blocking diodes are preferred
over silicon diodes.
Fuses, fuse holders, switches, and other components should be selected to satisfy both voltage and
current requirements.
All battery series branches should contain fuses.
Fused disconnects are strongly recommended to isolate the battery bank from the rest of the system.
Inverter