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Giving Up Alternating Current

Posted by Soulskill on from the you-shocked-me-all-night-long dept.

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?

19 of 466 comments (clear)

  1. Outdoor by Anonymous Coward · · Score: 5, Informative

    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.

    1. Re:Outdoor by Technician · · Score: 5, Interesting

      Due to the very poor selection of DC appliances and often their RV bloated price tags, I have opted to keep AC, but generate it locally. Instead of buying a DC to DC supply for a laptop to get 19V for about $100, I bought a 1KW inverter instead for about the same price. If I don't want all my lights to be Fluorescent Cool White in color, I can use the 9W 3K bulbs instead in a warm white with high Color Rendering Index >94%. Try it. Try to find 12V RV bulbs that are not Amber, Red, or Cool White 6K. Most of the outlets in my RV are running off the inverter. Only the kitchen and bath loop are still on traditional shore power or generator along with the AC. This limits the generator runtime where shore power is not handy.

      I have not trimmed my home use enough yet to cut loose from the grid. Heat pumps and long wet winters on solar just is not a match yet. They haven't fixed the solar when the sun doesn't shine problem yet.

      I don't have to mess around with trying to adapt everything to 12 or 24V. With a good size deep cycle battery, even normal microwave oven, blow dryer, other short duration high amperage loads are possible that is simply not an option on DC.

      --
      The truth shall set you free!
    2. Re:Outdoor by Jarik+C-Bol · · Score: 5, Interesting

      I lived in a house that was totally off grid. It actually was never on grid, because the owners already had a wind turbine back in the day when the utility companies where doing the rural electrification project, and declined to be added to the grid. This house had coal heat, gas and wood stoves, gas refrigeration, and no AC at all. Located in central Montana, it was equipped with a bank of around 12 CAT bulldozer batteries, (which replaced about twenty 1 gallon square glass jars with lead plates) over 200 square feet of solar panels, a small wind turbine (about a 2 foot blade) and a backup propane generator, that was set up to automatically start up and top up the system if it dropped below a certain charge level. So basically, all the system had for load was incandessent bulbs, and occasionally a television. In the winter, that generator ran intermittently during the day, and after dark, it ran until you went to bed, and shut all the lights off. Obviously, using LED's and more power efficient TV's is possible now, but it takes a hell of a setup to go all off grid. (you could not run a modern computer or a microwave on that system, the computers where to sensitive to the square sin of the inverters, and would randomly restart. Microwaves would pop breakers if not plugged in directly to the generator.)

      --
      I've decided to Diversify my Holdings. I've divided my cash between my left and right pockets, instead of all in one.
    3. Re:Outdoor by cptdondo · · Score: 5, Informative

      As someone who works in the RV industry, you're right to some extent. But also, appliances in houses do not get shaken, bumped, subjected to temps from well below freezing to 120*F, so the testing and quality is far more stringent.

      Lastly, we use a lot of appliances common to boats, and durability and repairability are also important. You can't go to Walmart when you're on a boat; you fix, patch, or do without.

      Our customers who installed dorm fridges because RV fridges are too expensive have found that the dorm fridges don't last too long.

  2. Its made from People! by chriskovo · · Score: 5, Funny

    Shouldn't it be powered by his sense of self importance? Or at least by PEOPLE!!

  3. Nonsense by Anonymous Coward · · Score: 5, Interesting

    He's still living on the electrical grid, he's just not using it at home.

    Also, WTF? "I enjoy doing laundry about as much as doing dishes. I get my clothing custom made in China for prices you would not believe and have new ones regularly shipped to me."

    1. Re: Nonsense by Anonymous Coward · · Score: 5, Interesting

      Wow I didn't even make it that far. This guy is clearly an idiot. He didn't get rid of his dirty fuel burning ways, he just outsourced them to others. Ordering new clothes is way worse than washing some. And as far as this soylent stuff is concerned wasn't it proven that supplements aren't very good and you need actual food to be healthy? Absorption rates of supplements aren't good from what I read and they should be used to supplement an actual healthy diet.

    2. Re: Nonsense by tlhIngan · · Score: 5, Insightful

      Wow I didn't even make it that far. This guy is clearly an idiot. He didn't get rid of his dirty fuel burning ways, he just outsourced them to others. Ordering new clothes is way worse than washing some. And as far as this soylent stuff is concerned wasn't it proven that supplements aren't very good and you need actual food to be healthy? Absorption rates of supplements aren't good from what I read and they should be used to supplement an actual healthy diet.

      Exactly. He "cut his consumption" down by externalizing it all. Basically pushing it off somewhere else and hiding it.

      That's like every other company out there - they pollute because the cost of pollution is basically free - the cost is externalized (well, it was until Obama introduced those regulations). When people complain about the "cost of complyihg" it means they're no longer externalizing the cost (free) and now having to pay for it.

      Basically this idiot is making himself feel better by making society worse. He doesn't do laundry - but the charity he donates clothes is forced to do it. He's basically pushed the environmental impact, energy and cost of laundry onto some other 3rd party. Or if they deem it too dirty, they'll just toss it in the garbage. To him, he's "in the clear" still because he didn't throw it away directly.

      Basically, the stuff this guy did was offload onto someone else - you can conceptualize this by asking - what happens if EVERYOHE did it? If it's truly for the environment, then if everyone did it, we'd be better off. If not, then no, it's not as good.

      For an example - say check your tire pressure - most people will probably be on the slightly low side. But if everyone then pumped their tires to the right pressure, society benefits from the reduced fuel consumption, cleaner air (less fuel, less pollutants, etc). That's a real net plus.

      Using less energy - that's a good thing too - or more renewables. But if you're claiming your coal-powered server in a datacenter isn't your concern if you remote into it, well...

      What this guy did would be like RMS asking someone to open Microsoft Word for him because he needs to do something, while claiming to be only using free software. (Yes, I know RMS doesn't do this, but it's an example).

      Plus, I'm sure he's got the income to support this kind of lifestyle - enough to make a point, but really, I think I'd give it to the climate change deniers. For they can poke enough holes in his "living arrangements" to basically say "if we agree to cut back, look at how we'll live - and look ,he's not even green if he needs all that stuff!".

      I'd say he's among the worst kind of "environmentalist" around - a green-washer.

    3. Re:Nonsense by jandrese · · Score: 5, Funny

      It's a real shame this guy hasn't found a generator that can run off of his sense of self satisfaction. It would end his energy problems forever.

      --

      I read the internet for the articles.
  4. He wasn't able to give it up. by FictionPimp · · Score: 5, Informative

    "For intensive tasks, he remotes to more powerful machines".

    So he can't survive without it....

    1. Re:He wasn't able to give it up. by bobbied · · Score: 5, Interesting

      AC by virtue of alternating, passes though zero current flow and zero voltage 120 times a second in this country. When you have an arc, you are passing an electric current though a plasma and that requires that you keep it hot and ionized. It is the current that keeps the plasma hot and ionized.

      As a switch contact opens, initially the distance between the contacts is under the flash over voltage and an arc of plasma is formed. This arc requires current to keep flowing though it to be maintained and as the contacts separate further the resistance of the plasma path increases, lowering the current. Eventually in AC circuits, the voltage needed to maintain the plasma path starts to cycle under this minimum value for longer and longer times and current starts to fall off on average. This falling current, makes the arc plasma start to fade and will eventually extinguish the arc during the times when the current and voltage cross the zero level.

      DC has no regular fall off in the plasma because it is always there, full on, full current. This means that switching similar voltages and currents in DC requires additional distance over AC. DC starts the arc and builds the plasma without stopping and only the resistance of the plasma as the distance increases is what will cause the current to get lower and lower until the arc extinguishes. There are no "off" times like there is in AC so the arc exists over a larger distance.

      ALSO, on very high voltage AC circuits, it is possible to disconnect the circuit during a zero crossing. In that case, assuming you can get the contacts far enough apart to avoid flashing over, there never will be an arc to start with. Even though it's mechanically difficult to move things that fast, they sometimes do this kind of thing to suppress the arc in AC. This doesn't work in DC because there is never a zero crossing.

      --
      "File to fit, pound to insert, paint to match" - Aircraft Maintenance 101
  5. DC is more dangerous by circletimessquare · · Score: 5, Insightful

    this experiment is fine if you're doing little LED lights and laptops, but if you're running something like air conditioning or a washing machine you're building a fire hazard and a mortality risk

    the decision to use AC over DC was not random nor taken lightly, there are many factors involved (heck, it was a major engineering, corporate, and PR war between Edison and Westinghouse: https://en.wikipedia.org/wiki/... ), but the right decision was made

    for our modern world where some people only care about their laptop and smartphone, it does indeed seem silly and wasteful to convert to AC then back to DC, especially if you've ever tried charging electronics in a car. but there are of course many other uses for electricity, and the navel gazing small electronics crowd is but a minor topic

    but i do see a time in the future as more people use local solar and other renewables, that a small DC subsystem is made available in the house for electronics like computers

    --
    intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
  6. Might as well be dead! No! More butter, more wine! by jabberw0k · · Score: 5, Funny

    No birthday cakes, no cherry pies, no fresh baked bread, no roast pork with caramelized potatoes, no steaks, no cauliflower broccoli cheese casserole, not even any homemade French onion soup? I shudder to think what Julia Child would say to that.

  7. These changes... by Pollux · · Score: 5, Insightful

    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?

    No. I have a wife.

  8. 50% is lost in AC to DC conversion? by vadim_t · · Score: 5, Insightful

    Sounds like he's badly confusing something. I think he's badly misunderstanding how a rectifier works. Some waste of course happens, but not nearly that much.

    1. Re:50% is lost in AC to DC conversion? by stackOVFL · · Score: 5, Informative

      Yeah, your right. The low efficiency of a DC power supply is in the 80% range. http://www.xppower.com/pdfs/TA...

  9. Think about the children! by Media+Archivist · · Score: 5, Interesting

    He has decided upon a very specific, and limiting, style of living. Bravo. Now try applying his philosophy to a household with children. Or a household frequented by guests. Try this in less sunny locales.

    I think it is admirable to try to be different, and to advocate alternative. I am completely turned off by his holier than thou attitude and his dismissiveness towards that which does not fit his chosen lifestyle.

  10. Hard to take serious. by bobmajdakjr · · Score: 5, Insightful

    Most of his personal savings just offload the burden of destruction to someone else, like taking uber (fossil fuels) and donating dirty clothes (water use, and being a scumbag donating dirty things) such that I was not entirely sure this was not satire.

  11. Why DC is a greater fire risk by Anonymous Coward · · Score: 5, Informative

    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.