Their job is to convert high-voltage alternating current from the mains into low-voltage direct current for mobile phones, laptops, iPods and other electronic gadgets.

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Traditional inverters gather power from all or most of the panels in an installation and use transformers, capacitors and switches to change it from direct current to alternating current.

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They can carry five to 20 times more current in the same unit area while reducing the amount of energy lost as heat by 75-97% (depending on whether the current is alternating or direct), even after accounting for all the nitrogen-cooling paraphernalia.

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