Because they finance the upfront cost of the solar system, they have an constant need for capital to reach scale.

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That's because meeting global energy needs requires constant investment on a scale unmatchable by economically uncompetitive sources like solar, wind and biofuels.

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While the ship will not travel at warp speed, with an ion propulsion engine powered by a 1.5GW nuclear reactor, it can travel at a constant acceleration so that the ship can easily get to key points of interest in our solar system.

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