Solar power needs to be converted from (DC, as it is generated from the panel) to (AC) to be injected into the power grid. Since solar panels generate peak power only for few hours each day, and DC to AC converters are expensive, the converters are usually sized to be smaller than the peak DC power of the panels. This means that for some hours each day the peaks are "" and the extra energy is lost. This has very little impact on the total e.
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