Hi All, I'm new to the forum and I have a question on the relationship between efficiency and area required per kW. I know when efficiency increases, the area required per kW reduces (proportionally?). So theoretically, multiplying efficiency and area required per kW would give a constant. But this is not the case, after I checked a few products on the market, even if they are the same type of PV panel.

For example, for monocrystallaine PV from Sunpower x-series, available at https://us.sunpower.com/sites/sunpow...lar-panels.pdf. There are two types of monocrystalline PV in this product sheet: SPR-X21-335-BLK and SPR-X21-345, with efficiency 21% and 21.5% respectively. The area required by each individual panel for these two types are the same (1558mm *1046 mm). The former has 335 W, while the latter has 345 W. But 345W divided by 335W does not equal to 21.5%/21%.

Is this expected, and why they are different? Could anyone help to explain the technical reasons behind? Thank you!

For example, for monocrystallaine PV from Sunpower x-series, available at https://us.sunpower.com/sites/sunpow...lar-panels.pdf. There are two types of monocrystalline PV in this product sheet: SPR-X21-335-BLK and SPR-X21-345, with efficiency 21% and 21.5% respectively. The area required by each individual panel for these two types are the same (1558mm *1046 mm). The former has 335 W, while the latter has 345 W. But 345W divided by 335W does not equal to 21.5%/21%.

Is this expected, and why they are different? Could anyone help to explain the technical reasons behind? Thank you!

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