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Sharp Announces Sales of DC Powered Air Conditioner, Other Products To Follow
AmiMoJo writes: Sharp has announced that sales of DC powered air conditioners will begin by the end of the year. Most appliances use the standard AC electricity supply in homes, but as solar panels become more common switching to DC can save on conversion losses. Solar panels produce DC, which is then typically converted to AC before being fed into the house's wiring, and then converted back to DC again by appliances. Sharp has announced that it intends to produce a range of DC powered appliances for home use.
Did he have anything against DC period, or just take the position that it wasn't so hot for transmission systems, especially since high efficiency DC-DC converters weren't exactly off the shelf items at the time?
AC has far lower transmission losses over long distances
Does it? I was always under the impression that AC was used for long-distance transmission because it could be easily stepped up to very high voltages with transformers while efficient DC-to-DC conversion was not possible until relatively recently. For the same power transmitted, resistive losses are lower at higher voltages as power lost to heat goes as I^2*R and lower currents could be used.
However, modern solid-state DC-to-DC converters are extremely efficient, can step DC voltages up to very high voltages and thus benefit from lower resistive losses in transmission. HVDC also benefits from not having to deal with inductive or capacitive losses in the cable.
In short, as far I know the key to minimizing losses in transmission lines is to use high voltages, not because of any inherent advantage of AC.
Stop being a dick, he made an assumption that was incorrect, when proven otherwise he adjusted his stance.
If everyone who made assumptions acted like him most of the world problems would be solved.