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4. Calculate Size of Solar Panel

CALCULATE SIZE OF SOLAR PANEL

Calculate Size of Solar Panel, No of Solar Panel and Size of Inverter for following Electrical Load

Electrical Load Detail:

  • 1 No’s of 100W Computer use for 8 Hours/Day * 2 No’s of 60W Fan use for 8 Hours/Day * 1 No’s of 100W CFL Light use for 8 Hours/Day

Solar System Detail:

  • Solar System Voltage (As per Battery Bank) = 48V DC * Loose Wiring Connection Factor = 20% * Daily Sunshine Hour in Summer = 6 Hours/Day * Daily Sunshine Hour in Winter = 4.5 Hours/Day * Daily Sunshine Hour in Monsoon = 4 Hours/Day

Inverter Detail:

  • Future Load Expansion Factor = 10% * Inverter Efficiency = 80% * Inverter Power Factor =0.8

CALCULATION:

Step-1: Calculate Electrical Usages per Day

  • Power Consumption for Computer = No x Watt x Use Hours/Day * Power Consumption for Computer = 1x100x8 =800 Watt Hr/Day * Power Consumption for Fan = No x Watt x Use Hours/Day * Power Consumption for Fan = 2x60x8 = 960 Watt Hr/Day * Power Consumption for CFL Light = No x Watt x Use Hours/Day * Power Consumption for CFL Light = 1x100x8 = 800 Watt Hr/Day * Total Electrical Load = 800+960+800 =2560 Watt Hr/Day

Step-2: Calculate Solar Panel Size

  • Average Sunshine Hours = Daily Sunshine Hour in Summer+ Winter+ Monsoon /3 * Average Sunshine Hours = 6+4.5+4 / 3 =8 Hours * Total Electrical Load =2560 Watt Hr/Day * Required Size of Solar Panel = (Electrical Load / Avg. Sunshine) X Correction Factor * Required Size of Solar Panel =(2560 / 4.8) x 1.2 = 635.6 Watt * Required Size of Solar Panel = 635.6 Watt

Step-3: Calculate No of Solar Panel / Array of Solar Panel

If we Use 250 Watt, 24V Solar Panel in Series-Parallel Type Connection

  • In Series-Parallel Connection Both Capacity (watt) and Volt are increases * No of String of Solar Panel (Watt) = Size of Solar Panel / Capacity of Each Panel * No of String of Solar Panel ( Watt) = 635.6 / 250 = 2.5 No’s Say 3 No’s * No of Solar Panel in Each String= Solar System Volt / Each Solar Panel Volt * No of Solar Panel in Each String= 48/24 =2 No’s * Total No of Solar Panel = No of String of Solar Panel x No of Solar Panel in Each String * Total No of Solar Panel = 3×2 =6 No’s * Total No of Solar Panel =6 No’s

Step-4: Calculate Electrical Load:

  • Load for Computer = No x Watt * Load for Computer = 1×100 =100 Watt * Load for Fan = No x Watt * Load for Fan = 2×60 = 120 Watt * Load for CFL Light = No x Watt * Load for CFL Light = 1×100 = 100 Watt * Total Electrical Load = 100+120+100 =320 Watt

Step-5: Calculate Size of Inverter:

  • Total Electrical Load in Watt = 320 Watt * Total Electrical Load in VA= Watt /P.F * Total Electrical Load in VA =320/0.8 = 400VA * Size of Inverter =Total Load x Correction Factor / Efficiency * Size of Inverter = 320 x 1.2 / 80% =440 Watt * Size of Inverter =400 x 1.2 / 80% =600 VA * Size of Inverter = 440 Watt or 600 VA

SUMMARY:

  • Required Size of Solar Panel = 635.6 Watt * Size of Each Solar Panel = 250 Watt. 12 V * No of String of Solar Panel = 3 No’s * No of Solar Panel in Each String = 2 No’s * Total No of Solar Panel =6 No’s * Total Size of Solar Panel = 750 Watt * Size of Inverter = 440 watt or 600 VA