Do solar panels in space produce way more power? Here's the math behind the claim

Solar power in orbit generates far more energy than panels on the ground. How big that gap actually is decides whether space computing is viable

NASA via Getty Images

The case for building AI data centers in space rests on a single claim: that solar panels in orbit generate dramatically more power than panels on the ground. Google $GOOGL's Project Suncatcher team has put the multiplier at up to eight times. Startups pitching investors on space-based computing have used the same number.

The claim compares a panel in near-continuous sunlight against one that contends with night, clouds, heat and seasonal variation across a full year. A solar farm that looks productive on a clear afternoon delivers far less when averaged across 12 months.

In the best-case orbital scenario, the eightfold multiplier holds. In a more typical comparison, it lands closer to five. The true cost of getting those panels into orbit has to be justified against a more modest power advantage.

The sun delivers a fixed amount of energy to anything in its path at Earth's distance. NASA's Goddard Space Flight Center and the NOAA Total Solar Irradiance Climate Data Record put the number at 1,361 watts per square meter,........

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