# Environmental Science: Numerical Questions – Solar Cell: Calculate Efficiency and Area

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## Type I – Calculate Efficiency

1. A single solar cell (10 cm × 10 cm) produces a voltage of 0.5 V and a current up to 2.5 A. If the solar insolation is 800 W/m^{2}, the efficiency of the solar cell is:

- ⁓15.6 %
- ⁓24.6 %
- ⁓12.3 %
- ⁓10.2 %

Answer: (A) ⁓ 15.6 %

Explanation:

Given Values.

S. I = 800 w/m^{2}

Voltage (V) = 0.5 V

Current (I) = 2.5 A

η = ?

Area = 10 cm × 10 cm = 10^{-2} m^{2 [}1 cm = 0.01m]

**η =** x 100 … (i)

Solar Insulation (S. I) **=** … (ii)

P_{out} = Voltage (V) x Current (I) … (iii)

Using (i) , (ii) and (iii) we can deduce.

*η* **=**

*η*

*η* **=**

*η* **=** 0.1562 = 15.62 %

The efficiency of the solar cell is 15.62 % .

## Type II – Calculate Area

2. A single solar cell on illumination by insolation of about 800 Wm ^{− 2} produces a voltage of 0.5 V and a current up to 2.0 A. The efficiency of the solar cell is 12.5 % . The area of the cell is:

- 2 × 10
^{− 2}m^{2} - 5 × 10
^{− 3}m^{2} - 4 × 10
^{− 4}m^{2} - (4) 10
^{− 2}m^{2}

Answer: (D) 10^{-2} m^{2}

Explanation:

Given data՚s.

SI = 800 w/m^{2}

Voltage (V) = 0.5 V

Current (I) = 2.0 A

N = 12.5 %

Area = ?

**η =** x 100 … (i)

Solar Insulation (S. I) **=** … (ii)

P_{out} = Voltage (V) x Current (I) … (iii)

Using (i) , (ii) and (iii) we can deduce.

**η =**

A =

A = 10^{-2} m^{2}

The Area of the cell is 10^{-2} m^{2} Hence option (D) 10^{-2} m^{2} is the correct answer.

## Type III – Calculate Power

3. Solar insolation on a rectangular module (1.5 m x 2.0 m) of photovoltaic cells is 550 W/m^{2}. If the efficiency of the cells is 12 % What is the power output of the module?

- 396 W
- 240 W
- 99 W
- 198 W

Answer: (D) 198 W

Explanation:

Given Values.

S. I = 550 W/m^{2}

η = 12 %= 0.12

Area = 1.5 m x 2.0 m = 3 m^{2}

Power = ?

**η =** x 100 … (i)

Solar Insulation (S. I) **=**

P_{in} = Area ⚹ S. I … (ii)

Using (i) and (ii) we can deduce.

*η* **=**

0.12 =

P = 0.12 ⚹ 550 ⚹ 3

P = 198 W

The power of the solar cell is 198 W

-Mayank