Lesson 2
Theoretical part
There are four modern types of solar panels: monocrystalline, polycrystalline, thin-film and concentrated. Monocrystalline solar panels are made from monocrystalline silicon. Their characteristic appearance includes a dark colour and rounded edges. They are very efficient thanks to the purity of the silicon. This is why their efficiency can exceed 20%. Monocrystalline silicon increases their durability, even when it comes to high temperatures. They also have a high power output. However, this makes them more expensive.
Polycrystalline solar panels also have a distinctive appearance: they are square panels with uncut corners, mostly blue. They are somewhat faster and cheaper to produce because they are made by melting raw silicon. They are cheaper, but have a slightly lower efficiency factor, which is around 15%. They are not as durable when exposed to high temperatures for long periods of time. However, the difference between them and monocrystalline panels is not as significant. Monocrystalline panels have slightly higher spatial efficiency, but when it comes to power output they are quite similar. Thin-film solar panels have thin-film solar cells and are mainly used for small solar power systems.
These panels are based on materials such as silicon, cadmium or copper. They are easy to manufacture, making them a cheaper option than other types of solar panels, given the fact that they require far less material to produce. In addition to being more affordable, such panels are also flexible. This makes them much easier to use and reduces their sensitivity to high temperatures. To create amorphous silicon solar panels, a three-layer technology is used, the best among thin-film materials. Given that they are easy to manufacture and low cost, their lifespan and warranty are shorter. Concentrated photovoltaic cell panels are multi-transition with an efficiency of 41%. They are very efficient 20 due to their curved mirror surfaces, lenses and cooling systems.
Experimental Week
This week, students will have to calculate the efficiency of the Titan 8 solar tracker
Step 1. The device was located in South Kazakhstan perpendicular to the sun, first of all I measured the current and voltage of the two-axis solar tracker, after which I did the same from a fixed panel, I took all the readings using an electrical measuring device, a multimeter. The result of the testimony was tabulated
The direction of the solar panel should initially be the same perpendicular to the rays of the sun.
| Tracker | Panel | Tracker | Panel | ||
| Time | I,А | I,А | U,В | P, Вт | P, Вт |
| 12:00 | 0,76 | 0,64 | 5,6 | 4,256 | 3,584 |
| 13:00 | 0,8 | 0,55 | 5,7 | 4,56 | 3,135 |
| 14:00 | 0,74 | 0,72 | 5,7 | 4,218 | 4,104 |
| 15:00 | 0,9 | 0,75 | 5,7 | 5,13 | 4,275 |
| 16:00 | 0,68 | 0,59 | 5,7 | 3,876 | 3,363 |
| 17:00 | 0,7 | 0,66 | 5,7 | 3,99 | 3,762 |
| 18:00 | 0,56 | 0,55 | 5,7 | 3,192 | 3,135 |
| 19:00 | 0,5 | 0,47 | 5,7 | 2,85 | 2,679 |
| 20:00 | 0,33 | 0,15 | 5,7 | 1,881 | 0,855 |
Step 2. In order to calculate the efficiency of the solar panel, you need to compare the power of radiation incident on the panel from the light source (power consumed) and the output power of the solar panel (useful power), and also determine the area of the solar panel. To determine the amount of solar insolation (the amount of irradiation of the surface by a beam of sunlight), I used the data
on the South Kazakhstan Region, which are shown in Table 2.
| Time | Solar insolationkWt*h /m2 | Optimal slope angle,С |
| January | 1,76 | 69 |
| February | 2,78 | 61 |
| March | 4,15 | 49 |
| April | 5,04 | 33 |
| May | 5,95 | 19 |
| June | 6,26 | 13 |
| July | 6,11 | 16 |
| August | 5,13 | 28 |
| September | 3,90 | 43 |
| October | 2,66 | 56 |
| November | 1,85 | 66 |
| December | 1,58 | 72 |
| Average value for 1 year | 3,93 | 43,75 |
Step 3. Now you need to calculate the area of the solar panel in order to determine the power consumed. The area is determined by the formula 1.
𝑆 = 𝑎 × 𝑏
These panels are Titan 8 (the whole group has one solar panel, for example, and therefore the panel area of the whole group should be the same)
a=1.791m
b=1.052m
Step 4. The power consumed is calculated according to formula 2.
P(p.con)=P(s) × S
P(s) = 1000 Wt*h/m2 – solar power
S, m2 – solar panel area
Step 5. The useful power is determined by the formula 3 data for U and I, we take from 1 table
here U [V] is the voltage from the boost module
I [A] – solar panel current
P(full.pow) = U × I
Step 6. The efficiency of the solar panel is found by formula 4.
η= P(full.pow)/P(p.con) * 100‰
P(full.pow) – full power
P(p.con) – power consumption
At the end of the experimental part, each group should exchange and check their calculations