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Giving Up Alternating Current
An anonymous reader writes: Yesterday we discussed Soylent, the artificial food substitute created by Rob Rhinehart and his team. As it turns out, this isn't Rhinehart's only unusual sustainability project. In a new post, he explains how he gave up on alternating current — a tough proposition for anyone living in the U.S. and still interested in using all sorts of modern technology. Rhinehart says, "Most power in the US is generated by burning coal, immediately squandering 67% of its energy, then run through a steam turbine, losing another 50%, then sent across transmission lines, losing another 5%, then to charge a DC device like a cell phone another 50% is lost in conversion. This means for 100 watts of coal or oil burned my phone gets a mere 16."
The biggest hindrance was the kitchen. As you might expect for the creator of Soylent, he doesn't cook, and was able to get rid of almost all kitchen appliances because of that. He uses a butane stove for hot beverages. He powers a small computer off batteries, which get their energy from solar panels. For intensive tasks, he remotes to more powerful machines. He re-wired his apartment's LED lighting to run off direct current. Have any of you made similar changes? How much of an effect does this really have?
The biggest hindrance was the kitchen. As you might expect for the creator of Soylent, he doesn't cook, and was able to get rid of almost all kitchen appliances because of that. He uses a butane stove for hot beverages. He powers a small computer off batteries, which get their energy from solar panels. For intensive tasks, he remotes to more powerful machines. He re-wired his apartment's LED lighting to run off direct current. Have any of you made similar changes? How much of an effect does this really have?
It's the new outdoor trend anyway. All the lighting is obviously LED, so no problem there, the gadgets all transform their AC to DC anyway, so no problem there as well, you just need a decent lab trafo.
Washers and dryers that use solar heated water are no problem either, they mix warm and cold as they need it.
Even the small 12 Volt Camping washing machines work very well nowadays.
You cook by gas and use a gas refrigeration unit as well.
There's a German project the 'direct current house' (in German obviously)
http://www.dasgleichstromhaus....
They have solved many problems.
"For intensive tasks, he remotes to more powerful machines".
So he can't survive without it....
Yeah, your right. The low efficiency of a DC power supply is in the 80% range. http://www.xppower.com/pdfs/TA...
DC arcs are strongly self-sustaining once ignited, as there's nothing to halt the continuous generation of ions which provide an easy conductive path. In contrast, AC arcs tend to self-extinguish twice a cycle when the voltage drops to zero, and so the AC arc has to re-ignite each cycle once the voltage rises high enough. Even if it does manage to re-ignite, the arc is not usually conducting the full cycle.
This reduced arcing makes AC a significantly lower fire hazard than DC, and the same effect happens to make AC switch contacts last much longer since breaking a circuit rarely arcs for more than a half cycle so contacts don't usually heat up and little metal is carried away from their surfaces.