Elon Musk said Tesla and SpaceX are each working on building 100 GW of solar manufacturing capacity in the US.

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Tesla has revealed a $10.1 billion proposal for a solar factory in Texas, offering the clearest look yet at how CEO Elon Musk could pursue his ambitions to ramp up solar manufacturing in the US, documents show.In a tax-incentive application filed in Texas, Tesla proposed a solar factory, code-named Project Crystal Sun, that would be built in Fort Bend County, southwest of Houston. The application said the facility would be expected to begin commercial operations in the first quarter of 2029 and employ more than 9,700 people full time.The application doesn't detail the factory's gigawatt output capacity, but cites a statement Musk made at the World Economic Forum in January about his two companies' solar ambitions."The SpaceX and Tesla team, both separately, are working to build to 100 GW a year of solar power in the US — of manufactured solar power," he said. "That'll probably take us three years or something. These are pretty big numbers, and I'd encourage others to do the same."For comparison, the Solar Energy Industries Association reported in August that the US currently has 74.1 GW of operational module manufacturing capacity, which is enough to supply about 170% of expected US demand in 2026.The Texas filing provided clues into how deep Tesla wants to go with its solar manufacturing capabilities. The company said it would manufacture "photovoltaic solar cells and/or assembled solar modules," while listing equipment related to key stages further up the solar supply chain.A Tesla spokesperson and representatives for Project Crystal Sun did not respond to a request for comment.