Consider a small module based on interconnected tandem cells of hydrogenated amorphous and microcrystalline silicon as depicted in the figure below. The Voc of a single tandem cell is 1.35V and the short-circuit density Jsc is 12mA/cm2.
b) Voc,module=16.2V, Isc,module=120mA
B is the answer
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To find the number of tandem cells in the module, we can use the following equations:
Voc,module = N × Voc,cell
Isc,module = N × Jsc × A
Where:
Voc,module is the open-circuit voltage of the module (16.2V),
N is the number of tandem cells in the module,
Voc,cell is the open-circuit voltage of a single tandem cell (1.35V),
Isc,module is the short-circuit current of the module (120mA),
Jsc is the short-circuit current density of a single tandem cell (12mA/cm2), and
A is the area of a single tandem cell (in cm2).
Let's start by finding the number of tandem cells (N):
N = Voc,module / Voc,cell
N = 16.2V / 1.35V
N ≈ 12
So, there are approximately 12 tandem cells in the module.
To answer this question, we need to understand the concept of a tandem solar cell module and how multiple tandem cells are interconnected to form the module.
A tandem solar cell module is a type of solar panel that consists of interconnected tandem cells. These tandem cells are made up of different layers of materials, such as hydrogenated amorphous silicon and microcrystalline silicon, that work together to increase the overall efficiency of the solar panel.
The question asks for the Voc and Isc values of the tandem cell module, given the Voc and Jsc values of a single tandem cell.
The Voc, or open-circuit voltage, of a solar cell is the maximum voltage that can be obtained from the cell when there is no external load connected. In this case, the Voc of a single tandem cell is given as 1.35V.
The Isc, or short-circuit current density, of a solar cell is the current that flows through the cell when there is no external load connected and the voltage across the cell is zero. In this case, the Jsc of a single tandem cell is given as 12mA/cm2.
To find the Voc,module and Isc,module of the tandem cell module, we need to consider how the individual tandem cells are interconnected. Since we are given only the Voc and Jsc values of a single tandem cell, we can assume that the module consists of multiple identical tandem cells connected in series.
When cells are connected in series, the total voltage of the module is equal to the sum of the individual cell voltages. So the Voc,module can be calculated by multiplying the Voc of a single tandem cell by the number of cells in the module. In this case, if the module consists of N tandem cells, then:
Voc,module = Voc,single cell * N
Given that the Voc of a single tandem cell is 1.35V, and the question states that the Voc,module is 16.2V, we can calculate the number of cells in the module as follows:
N = Voc,module / Voc,single cell = 16.2V / 1.35V = 12 cells
Therefore, the module consists of 12 tandem cells.
To calculate the Isc,module of the module, we need to understand how the current behaves when cells are connected in series. When cells are connected in series, the current through each cell is the same, and the total current of the module is equal to the current of a single cell. So:
Isc,module = Isc,single cell
Given that the Jsc of a single tandem cell is 12mA/cm2, the Isc,module of the module is also 12mA/cm2.
Therefore, the answer is:
b) Voc,module = 16.2V, Isc,module = 12mA/cm2