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LiveWire Harley electric motocrycle
Wealth bestows power, and that's one of the big reasons why the events in Iraq matter so much. In that beleaguered nation, the wealth bubbling up out of the ground is literally power by the barrel, labeled O-I-L, and it often spells death. It's long past time to excise ruthless dictators, religious fanatics, unstable regimes and dangerous industries out of our collective, critical energy loop:
Billionaire, Tesla founder, and private space entrepreneur Elon Musk announced yesterday that Solar City, the solar installation company where he is chairman, plans to acquire a startup called Silevo for $200 million (plus up to $150 million more if the company meets certain goals). And with typical bravado, he also said that the company plans to build a huge factory to produce Silevo’s high-efficiency solar panels, a strategy he claims will make solar power “way cheaper” than power from fossil fuels.
  • The motorcycle in the image above? That's an electric Harley!
  • Both ghoulish and fascinating: an electro-chemical process takes the fat out of pickled brains and leaves behind the delicate, intact neural structures for study.
  • Is the Earth's turbulent magnetic field weakening, moving, or about to flip?
  • Solar energy looks like a solid growth industry to me. One where the technology is finally far enough along to help us break away from the glaring shortcomings of a 20th century energy policy cobbled together to power a 19th century industrial revolution. I'm interested in looking at some articles/interviews on the state of that science and technology if anyone in the biz is up for it.
  • Enough of that electro-magnetic energy stuff! Here's some bloody wet science to help tide Game of Thrones fans over the summer dry spell:
    Europe's most well-known extinct humans, the Neanderthals, probably evolved their distinctive facial features in a chaotic "Game of Thrones" manner, as their ancestors clashed and competed in a harsh Ice Age environment, researchers say.

Originally posted to Daily Kos on Sat Jun 21, 2014 at 06:00 AM PDT.

Also republished by SciTech.

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Comment Preferences

  •  Thanks DarkSyde (19+ / 0-)

    I voted Tuesday, May 6, 2014 because it is my right, my responsibility and because my parents moved from Alabama to Ohio to vote. Unfortunately, the republicons want to turn Ohio into Alabama.

    by a2nite on Sat Jun 21, 2014 at 06:17:54 AM PDT

  •  Electric Harley: A Tesla strategy (18+ / 0-)

    Not to say a production LiveWire would necessarily be very expensive, just that it is very very cool and, I think, a desirable bike.

    They spent a lot of time and effort to trim weight and to get the sound right. It looks good, and, with 75 hp on a 460 lb bike, goes pretty damned well, too.

    The prototypes will help them to get the details right (more range? Different sound? More performance?)

    This, ultimately, is the surest way to move into a sustainable economy: people go green because the coolest and/or most desirable things -- and ways of operating -- are green.

    LG: You know what? You got spunk. MR: Well, Yes... LG: I hate spunk!

    by dinotrac on Sat Jun 21, 2014 at 06:22:57 AM PDT

    •  Dude....your Harley is so.........quiet. (10+ / 0-)

      Legal means "good".
      [41984 | Feb 4, 2005]

      by xxdr zombiexx on Sat Jun 21, 2014 at 06:25:21 AM PDT

      [ Parent ]

    •  Dude....your Harley is so......quiet (4+ / 0-)

      Legal means "good".
      [41984 | Feb 4, 2005]

      by xxdr zombiexx on Sat Jun 21, 2014 at 06:26:21 AM PDT

      [ Parent ]

    •  i suspect it's a brand test (4+ / 0-)
      Recommended by:
      dinotrac, ditsylilg, BlackSheep1, Wee Mama

      i suspect Harley is trying to get a vehicle they can
      sell to millenials.

    •  Sound is important for more than just (3+ / 0-)
      Recommended by:
      dinotrac, gchaucer2, tb mare

      esthetic reasons, but also safety ones. People need an auditory indication that a vehicle is approaching to they don't get in its way. This is especially true for visually impaired pedestrians, but also drivers of other vehicles. NYC recently banned electric bikes for just that reason.

      "Reagan's dead, and he was a lousy president" -- Keith Olbermann 4/22/09

      by kovie on Sat Jun 21, 2014 at 06:38:31 AM PDT

      [ Parent ]

      •  That's an easy fix (10+ / 0-)

        A menu of sounds will be the equivalent of ringtones for all electric vehicles. Wanna sound like a Classic Harley? A Vespa? Maybe you're feeling "playing card on bicycle spoke" this morning....

        Change does not roll in on the wheels of inevitability, but comes through continuous struggle. --Martin Luther King Jr.

        by Egalitare on Sat Jun 21, 2014 at 06:46:41 AM PDT

        [ Parent ]

      •  The ban is about speeding, not electrics (5+ / 0-)

        It's unfortunate that hooligans can now easily drive 30 mph on [electric] bicycles, and then hit people. And then electric bikes get banned…

        This is a speed enforcement issue in a high density urban environment. Electric motorcycles on the open road are not the same. In either case, safety is the responsibility of the bike operator, and those who step in to the street, whether deaf or not.

        As the operator of a very quiet 500+ pound BMW motorcycle I know my closing speed coming up on folks at overlooks on the Blue Ridge Parkway, for instance, doesn't give them reaction time to the quiet whistling of my approach, if they don't LOOK because they have decided to step in the road. Never step in the road without looking, but if you do, don't blame the vehicle that hits you.

        As a trained and experienced rider, I cover the brake and slow, and I look out for stupid, and kids, who don't yet know that stepping into traffic can have dire consequences.

        Trying to make Prius's roar sand electric bikes loud is stupid. Quiet please. And ticket these Harley's with the cut off pipes. We're going deaf, and these loud pipes aren't saving any lives---they are just being obnoxious and seeking cheap unfavorable attention. Gives motorcycles a bad name.

        My bike, typical in that it tops at (electronically) at 125 mph (it's a dual sport), is as quiet as any car, has a catalytic converter, and can carry a quarter of a ton. I can't wait for the electric model. Silly some legislative bodies want to impede progress in that direction, because of operator behavior. Don't blame the technology. Most of us ride responsibly.

        •  I can exceed 30mph on my road bike (2+ / 0-)
          Recommended by:
          PeterHug, dinotrac

          As in (motorless, other than me and my legs ) bicycle, on the flats, and it's very quiet. By the time pedestrians can hear me, if they didn't see me coming, it's too late for either of us to avoid a collision. Which is why I ride as you do, very carefully and defensively, taking upon myself nearly all the burden of avoiding collisions, with people and vehicles. I assume nearly nothing other than that others don't and won't see me so I have to anticipate possible collisions and avoid them, by slowing down, moving to one side or another, indicating my approach, etc. To date I have a perfect record with well over 10k ridden.

          Most people who cycle can't get to anywhere near such a speed, nor do they try. Those who can, and do, I'm guessing tend to be similarly responsible. The sort of person who can afford a road bike that can go that fast, and rides often enough to be able to get up to such a speed, is likely to be smart, mature and responsible enough to not do anything stupid.

          However, I'm not convinced that people who own and ride electric bikes are likely to be as responsible, which is why I think that mandating some sort of sound, either continuous or proximity-activated, is necessary.

          These are the same idiots who hog an entire bike path or do sudden u-turns without looking. Nearly all of the near-misses I've had were with these Darwin Award winners. Laws and rules exist mostly to deal with them.

          "Reagan's dead, and he was a lousy president" -- Keith Olbermann 4/22/09

          by kovie on Sat Jun 21, 2014 at 07:54:53 AM PDT

          [ Parent ]

          •  I think I only hit 30 mph once (except on hills) (2+ / 0-)
            Recommended by:
            PeterHug, BlackSheep1

            I was being chased by a very angry dog.

            If the pilot's good, see, I mean if he's reeeally sharp, he can barrel that baby in so low... oh you oughta see it sometime. It's a sight. A big plane like a '52... varrrooom! Its jet exhaust... frying chickens in the barnyard!

            by Major Kong on Sat Jun 21, 2014 at 08:08:43 AM PDT

            [ Parent ]

            •  It's a major high (1+ / 0-)
              Recommended by:
              dinotrac

              Downhill I've exceeded 40mph. I can go much faster, but don't have enough confidence in myself to try. In certain things, cowardice is honorable.

              Unless a bear is chasing me. I hear they can do 40mph.

              "Reagan's dead, and he was a lousy president" -- Keith Olbermann 4/22/09

              by kovie on Sat Jun 21, 2014 at 09:41:12 AM PDT

              [ Parent ]

          •  Ah, to be young again. 30 years ago I could top (1+ / 0-)
            Recommended by:
            kovie

            30 on the flat (and, on occasion, had drivers told me I did exactly that at stop signs).

            You're right -- fear of Splat makes you very wary on a bicycle, which loses to nearly anything it collides with.

            LG: You know what? You got spunk. MR: Well, Yes... LG: I hate spunk!

            by dinotrac on Sat Jun 21, 2014 at 07:39:27 PM PDT

            [ Parent ]

            •  I'm not that young anymore (1+ / 0-)
              Recommended by:
              dinotrac

              Yet I'm riding better than I ever have. I can now break the speed limit on all but major roads here. But I'm very unlikely to ever hit my age again. That last happened 10 years ago and I'd like to keep my face and skeleton intact.

              "Reagan's dead, and he was a lousy president" -- Keith Olbermann 4/22/09

              by kovie on Sat Jun 21, 2014 at 09:49:39 PM PDT

              [ Parent ]

      •  Stick a horn on it (3+ / 0-)
        Recommended by:
        PeterHug, Laurel in CA, BlackSheep1

        Give it one with a friendly little "Hey I'm here" sound

        and another with the "Get the hell outta my way!!!" sound

        If the pilot's good, see, I mean if he's reeeally sharp, he can barrel that baby in so low... oh you oughta see it sometime. It's a sight. A big plane like a '52... varrrooom! Its jet exhaust... frying chickens in the barnyard!

        by Major Kong on Sat Jun 21, 2014 at 08:15:44 AM PDT

        [ Parent ]

        •  Damn, now I can't remember -- Major, (0+ / 0-)

          is there anything on a BUFF to serve as a collision warning?

          The GPUs at Barksdale made enough noise, and then once the crew lit off the GE engines on the wings of course nobody could miss the proximity on the ground / approach / departure.

          What about later?   (I left in '80...)

          LBJ, Van Cliburn, Ike, Wendy Davis, Lady Bird, Ann Richards, Barbara Jordan, Molly Ivins, Sully Sullenburger, Drew Brees: Texas is NO Bush League!

          by BlackSheep1 on Sat Jun 21, 2014 at 09:29:13 AM PDT

          [ Parent ]

          •  They probably now have TCAS (1+ / 0-)
            Recommended by:
            BlackSheep1

            The KC-135s were retrofitted with it back in the 1990s.

            I believe it was done so that we could operate in RVSM (Revised Vertical Separation Minimums) airspace.

            TCAS stands for Terminal Collision Avoidance System. The transponders in the aircraft monitor each other and will give instructions "Climb!" or "Descend!" if two planes are on a collision course.

            If the pilot's good, see, I mean if he's reeeally sharp, he can barrel that baby in so low... oh you oughta see it sometime. It's a sight. A big plane like a '52... varrrooom! Its jet exhaust... frying chickens in the barnyard!

            by Major Kong on Sat Jun 21, 2014 at 09:48:36 AM PDT

            [ Parent ]

            •  That's what I was hoping to hear (0+ / 0-)

              Those of us not in the air just have to depend on the ground-shaking. :)

              LBJ, Van Cliburn, Ike, Wendy Davis, Lady Bird, Ann Richards, Barbara Jordan, Molly Ivins, Sully Sullenburger, Drew Brees: Texas is NO Bush League!

              by BlackSheep1 on Sat Jun 21, 2014 at 09:49:55 AM PDT

              [ Parent ]

        •  People are conditioned to expect engine noises (1+ / 0-)
          Recommended by:
          dinotrac

          in approaching vehicles, and are often startled with unexpected results by last-minute horns. I can't tell you how many morons I have to shout at as I approach them on my road bike because they're hogging the entire path, who often jump in panic as if they'd never been passed by a bike in their lives.

          When safety is involved, you engineer to the dumbest common denominator.

          "Reagan's dead, and he was a lousy president" -- Keith Olbermann 4/22/09

          by kovie on Sat Jun 21, 2014 at 10:01:12 AM PDT

          [ Parent ]

      •  this doesn't make sense. A peddled bike is just (1+ / 0-)
        Recommended by:
        dinotrac

        as quiet as an electric bike. There must be something else afoot here.

        •  Most cyclists can't go much faster than 20-25mph (1+ / 0-)
          Recommended by:
          dinotrac

          EVs can go much faster, and have a lot more mass. My road bike weighs 18.5lbs and that's considered to be on the heavy side these days. The combination of both makes them a lot more dangerous.

          "Reagan's dead, and he was a lousy president" -- Keith Olbermann 4/22/09

          by kovie on Sat Jun 21, 2014 at 03:07:37 PM PDT

          [ Parent ]

    •  What a beautiful machine. (8+ / 0-)

      Engineering is important (and environmental engineering is becoming mandatory), but design is everything.  

      "All that is necessary for evil to triumph is for good men to do nothing" - Edmund Burke

      by SueDe on Sat Jun 21, 2014 at 06:40:58 AM PDT

      [ Parent ]

    •  Brammo is already making electric bikes (5+ / 0-)

      Check them out at Brammo.com.

      Are Chris Christie and NJ are probably blocking them from sales, just as Tesla is blocked in some states for not having middleman distributors adding costs to the supply chain with no value?

      The century old iconic motorcycle race event, the Isle of Man TT, has an electric bike race category. An excellent documentary about the earlier efforts to campaign an electric bike, and to crack the 100 mph average lap speed on this difficult and windy 36 open mile road course is Mark Neale's Charge. reviewed at http://motorcycles.about.com/...

      BMW has developed an electric bike, too. Coming soon, for real:
      http://motorcycles.about.com/...

    •  "A Tesla strategy" (3+ / 0-)
      Recommended by:
      PeterHug, offgrid, BlackSheep1

      http://www.wired.com/...

      three-phase AC induction motor reverberates
      Alternating Current electric motors for identical size have more torque and Horse power that direct current motors for the same physical dimensions electric motor. Which is what gives the Teslas their kick.

      http://en.wikipedia.org/...

      The Tesla Roadster uses an AC motor descended directly from Tesla's original 1882 design.[
      The down side is you lose about 20% of your battery charge in the conversion using devices known as Voltage inverters. Inverters are at the heart of any home Solar power setup.

       

      I want 1 less Tiny Coffin, Why Don't You? Support The President's Gun Violence Plan.

      by JML9999 on Sat Jun 21, 2014 at 07:33:20 AM PDT

      [ Parent ]

  •  If Neanderthals had just invented guns (4+ / 0-)
    Recommended by:
    Aunt Pat, orlbucfan, ditsylilg, Hannibal

    there's be no global warming now......

    Legal means "good".
    [41984 | Feb 4, 2005]

    by xxdr zombiexx on Sat Jun 21, 2014 at 06:24:39 AM PDT

  •  The Electric Harley Doesn't (5+ / 0-)

    spew oil and unburned gasoline, make god-awful amounts of deafening noise, break down frequently,  and rattle your spine to the point where your need back surgery . . . . . . so it may take a while to catch on with bikers who hate rice-burning crotch rockets.

  •  the CLARITY method for clearing brains is yet (5+ / 0-)

    again another revolutionary development from the Deisseroth lab. He may very well win 2 nobel prizes - one for optogenetics and one for this. thanks to the link to the new article.

    "None of us got where we are solely by pulling ourselves up by our bootstraps" Thurgood Marshall

    by UTvoter on Sat Jun 21, 2014 at 06:26:36 AM PDT

  •  A question for solar experts (5+ / 0-)
    Recommended by:
    judyms9, orlbucfan, nzanne, PeterHug, offgrid

    How much energy loss typically takes place when converting the relatively low voltage DC output of solar panels to the high-voltage AC needed to transmit it long distances and power most appliances and devices, especially compared to dynamo-based electricity production, be it wind, hydro or fossil fuel-powered, which I believe puts out AC directly (no pun intended)?

    We're talking potentially 2 levels of energy loss here. One is in converting low voltage solar DC to low voltage AC, and the other is in then stepping up that low voltage to a higher voltage comparable to what's put out by dynamos, both of which then get stepped up to much higher voltages for long-distance transmission. What's the energy loss in each step?

    I'm guessing that this adds enough to solar's costs to make it a factor in determining whether it's cost-efficient for end users to replace or supplement conventional electricity generation with solar, putting aside externalities and government incentives both positive and negative.

    "Reagan's dead, and he was a lousy president" -- Keith Olbermann 4/22/09

    by kovie on Sat Jun 21, 2014 at 06:28:53 AM PDT

    •  that's a good question (5+ / 0-)
      Recommended by:
      kovie, orlbucfan, nzanne, ditsylilg, PeterHug

      Given the rise of large utility scale solar farms, i'm
      not sure it's a big problem

      but  most of the inverters i've been looking at are above
      90%  and most Transformers have been at 99% for
      a long time,  i'd say you lose between 4-11%

      taking 28VDC off of panels and making it into HV-AC

      now bear in mind most conventional coal fired
      electrical plants are only 30% thermally efficient,
      so,  don't feel like solar is horrendous

      •  I'm glad to hear that the loss is so low (3+ / 0-)
        Recommended by:
        orlbucfan, PeterHug, BlackSheep1

        Which combined with the low efficiency of fossil fuel-powered electricity and its obviously high externality costs makes it competitive with the latter.

        I've been tinkering with basic electronics recently as a hobby and was thinking of building a simple solar cell inverter, for the hell of it.

        Of course, this only applies to PV cell-based panels, not thermal panels that power what I assume are polyphase AC generators that put out MV AC.

        "Reagan's dead, and he was a lousy president" -- Keith Olbermann 4/22/09

        by kovie on Sat Jun 21, 2014 at 06:48:44 AM PDT

        [ Parent ]

        •  not sure how Solar Thermal works (1+ / 0-)
          Recommended by:
          PeterHug

          if it's DC rectified or spinning AC synchronous.

          DC would be easier to work with but less efficient.

          •  Not sure I used the correct term (0+ / 0-)

            But I meant solar energy captured as heat, not electricity, to power steam engine turbines, which in turn drive generators. I assume that the latter are generally polyphase alternators because they're most efficient for long-term transmission, but obviously it can be any sort of generator, AC or DC.

            "Reagan's dead, and he was a lousy president" -- Keith Olbermann 4/22/09

            by kovie on Sat Jun 21, 2014 at 09:44:40 AM PDT

            [ Parent ]

    •  Learn about the micro inverter... (6+ / 0-)

      Start with Enphase, as one market maker brand, but many others have come along. Each panel gets a small inverter mounted with it on the roof putting out 240 VAC on the spot. Arrays and strings of collectors aren't all or nothing producing or not, connected to one big inverter in the basement or garage.

      These digital inverters also talk to your PC with ethernet over power wire protocol, so you can monitor each panel separately and total system outputs.

      That this technology allows one to buy a few panels at a time, adding capacity and dropping load away from your monopoly utility makes this a disruptive technology. This, and the falling prices of solar are some reasons utilities are having state governments and PSCs erect barriers to solar and silly fees for solar -supplemtned customers.

      Search guerrilla solar…and hang a fe panels out back, plugged in.

      •  Thanks, this sounds interesting! (1+ / 0-)
        Recommended by:
        PeterHug

        Do these panels give you the option of bypassing the inverters to use their DC output directly, use your own inverters, or connect panels in series or parallel before putting their output through an inverter?

        "Reagan's dead, and he was a lousy president" -- Keith Olbermann 4/22/09

        by kovie on Sat Jun 21, 2014 at 06:42:55 AM PDT

        [ Parent ]

      •  What are the economics? (3+ / 0-)
        Recommended by:
        kovie, nzanne, PeterHug

        Are micro inverters cost effective compared to traditional inverters?

        I'm a 4 Freedoms Democrat.

        by DavidMS on Sat Jun 21, 2014 at 06:46:12 AM PDT

        [ Parent ]

        •  Depends on the scale of the project. (2+ / 0-)
          Recommended by:
          PeterHug, offgrid

          Residential and even small commercial - absolutely. 200-500 kW start moving into distributed inverters - smaller inverters per grouping of PV panels. Both the micros and DIs are nice because if one goes haywire it can easily be isolated and fixed while you're still getting production from the rest of the system.

          “I’d put my money on the sun and solar energy. What a source of power! I hope we don’t have to wait until oil and coal run out before we tackle that.” Thomas Edison, 1931

          by nzanne on Sat Jun 21, 2014 at 06:57:31 AM PDT

          [ Parent ]

        •  I just googled them (3+ / 0-)
          Recommended by:
          nzanne, PeterHug, Just Bob

          and there are certain advantages of MI's:

          Microinverters have several advantages over conventional central inverters. The main advantage is that small amounts of shading, debris or snow lines on any one solar panel, or even a complete panel failure, do not disproportionately reduce the output of the entire array. Each microinverter harvests optimum power by performing maximum power point tracking for its connected panel.
          ...
          The main problem with the "string inverter" approach is the string of panels acts as if it were a single larger panel with a max current rating equivalent to the poorest performer in the string. For example, if one panel in a string has 5% higher resistance due to a minor manufacturing defect, the entire string suffers a 5% performance loss. This situation is dynamic. If a panel is shaded its output drops dramatically, affecting the output of the string, even if the other panels are not shaded. Even slight changes in orientation can cause output loss in this fashion. In the industry, this is known as the "Christmas-lights effect", referring to the way an entirely string of series-strung Christmas tree lights will fail if a single bulb fails.

          Additionally, the efficiency of a panel's output is strongly affected by the load the inverter places on it. To maximize production, inverters use a technique called maximum power point tracking (MPPT) to ensure optimal energy harvest by adjusting the applied load. However, the same issues that cause output to vary from panel to panel, affect the proper load that the MPPT system should apply. If a single panel operates at a different point, a string inverter can only see the overall change, and moves the MPPT point to match. This results in not just losses from the shadowed panel, but the other panels too. Shading of as little as 9% of the surface of an array can, in some circumstances, reduce system-wide power as much as 54%.

          "Reagan's dead, and he was a lousy president" -- Keith Olbermann 4/22/09

          by kovie on Sat Jun 21, 2014 at 06:58:02 AM PDT

          [ Parent ]

    •  I have always thought that the best approach (0+ / 0-)

      to having a home PV system would be to keep the electricity DC, and convert your house to all-DC.

      And solar thermal as well - use it primarily to heat, and keep the energy thermal throughout the process as far as possible.

      •  How is one to then power typical devices (2+ / 0-)
        Recommended by:
        Just Bob, PeterHug

        like computers, microwaves, TVs, etc., which are all AC? Converting a house to all-DC would be a huge and I think pointless expense.

        "Reagan's dead, and he was a lousy president" -- Keith Olbermann 4/22/09

        by kovie on Sat Jun 21, 2014 at 09:45:47 AM PDT

        [ Parent ]

      •  From a pure efficiency point of view (1+ / 0-)
        Recommended by:
        PeterHug

        using DC directly may be more efficient, but it's not practical, at least not with household lighting and appliances that are currently available.

        DC voltages over about 50 VDC present a much higher shock and fire hazard than AC voltages over 50 VAC, so higher-voltage DC is not currently allowed in residential and commercial power systems. There are industrial uses, but only with very expensive safety features.

        Running low-voltage DC through any length of wire has higher loses, requiring larger wires, which cost a lot more and are much harder to install. DC appliances are also harder to find and typically a lot more expensive.

        The 10-15% inversion loss from a 48 VDC battery to 120/240 VAC for use in the house is more than made up by the lower cost of the wiring, switches, and appliances used.

        When I built my current off-grid house back in 1990, I dual-wired it for both AC and DC loads, primarily because PV power was so expensive at that time, and DC lighting was a lot more efficient than AC lighting. These days, PV is MUCH cheaper, and AC lighting MUCH more efficient. I long ago converted all of my DC circuits to AC to use power from my inverter.

        "If you lose your sense of humor, it's just not funny anymore" Wavy Gravy

        by offgrid on Sat Jun 21, 2014 at 11:35:04 AM PDT

        [ Parent ]

    •  more complex (0+ / 0-)

      And plant where you are burning fuel, be it coal, gas, or nuclear, has many ineffeciencies.  The fuel has to be burned, which has loss, the heat has to boil the water or whatever, and the turbines have to be turned.  Obviously in hydroelectric there is less ineffeciency.  However, a coal plant wastes the majority or potential energy of fuel, at least about 60%.

      With solar cells the efficiency only effect the number of cells one needs.  The output effeciency is about the same as coal, 40%, but there is no waste product.

      The transmission losses are comparable in the short. In the long term, were houses might have solar cells combined with fuel cells to store the power, the losses will be less.  After all, how much of your electricity need to be AC? I would guess only the air conditioning or fans and the refrigerator.  Everything else is DC.

      She was a fool, and so am I, and so is anyone who thinks he sees what God is doing. -Kurt Vonnegut Life is serious but we don't have to be - me

      by lowt on Sat Jun 21, 2014 at 08:58:29 AM PDT

      [ Parent ]

      •  Pretty much anything that plugs into a wall outlet (0+ / 0-)

        is AC, either inherently or in the input stage. Even a TV, which I assume runs on DC internally (but I may be wrong), has to connect to an AC outlet. You'd have to convert all your devices to DC to go all-DC, which sounds like a major, expensive and unnecessary hassle.

        "Reagan's dead, and he was a lousy president" -- Keith Olbermann 4/22/09

        by kovie on Sat Jun 21, 2014 at 09:47:58 AM PDT

        [ Parent ]

        •  most devices now (0+ / 0-)

          Some wall outlets have a USB charging port.  If we ever have local power supply, it would be simple enough to spec an outlet with AC plug, a USB plug, and DC plug.  As long as the ports are different there is no issue.  All that a standard DC plug, say 12VDC, would require is a different wall wart.

          She was a fool, and so am I, and so is anyone who thinks he sees what God is doing. -Kurt Vonnegut Life is serious but we don't have to be - me

          by lowt on Sat Jun 21, 2014 at 02:34:54 PM PDT

          [ Parent ]

          •  What uses DC directly, though? (0+ / 0-)

            I suppose devices that use an external adapter but not USB, like laptops, external HDs, wireless phones, etc. But even then there are different voltages and currents, so I don't see a universal DC jack for quite some time.

            "Reagan's dead, and he was a lousy president" -- Keith Olbermann 4/22/09

            by kovie on Sat Jun 21, 2014 at 03:03:27 PM PDT

            [ Parent ]

      •  Oh, also (0+ / 0-)

        I realize that traditional power generation has lots of waste and inefficiency, plus all that crap being dumped into the air, water and land. But it does produce AC inherently, without conversion. One really has to look at the entire generation process and factor in all sorts of internal and external variables to know which method makes most sense for a given application. Hopefully someday soon that will almost always mean green energy.

        "Reagan's dead, and he was a lousy president" -- Keith Olbermann 4/22/09

        by kovie on Sat Jun 21, 2014 at 09:54:47 AM PDT

        [ Parent ]

    •  Losses (1+ / 0-)
      Recommended by:
      kovie

      Of course anytime you convert one form of electrical energy to another form there are some losses. No process like this is 100% efficient.

      PV modules are rated for power (Watts) using a standardized test (Standard Test Conditions or STC) at the factory. While this does allow us to compare apples to apples when evaluating different PV modules, under most normal operating conditions in the real world, they rarely reach that amount of power production. Exceptions are conditions that allow for higher output, such as cold weather (PV module voltage rises at lower temps), higher altitude (higher solar insolation due to lower air mass), and reflectance from clouds, water surfaces or snow (increasing the amount of light reaching the surface of the module).

      Typically, a PV module will average about 90% of its STC rating in most places in the US averaged over the course of the year. So a module rated at 250W STC will show an actual average power output of about 225W.

      While a typical full sized 60-cell module in the 230-280W range (the most common used these days) has a rated STC operating peak-power voltage of about 30 VDC (called its "Vmp" or voltage at maximum power), they are typically installed in "strings" of modules connected in series. Connecting modules in series is additive in DC voltage, so if you connect 12 of them in series you end up with about 360 VDC (Vmp at STC; in very hot weather that might drop to as low as 300 VDC). Inverting 300+ VDC to 240 VAC does not require much voltage conversion (with a transformer in the inverter), so losses at that stage are minimal.

      Most battery-less utility intertie inverters ("Grid-tie", and the most commonly installed in most PV installations) are in the 96-98% efficiency range these days, so they are very efficient.

      Other systemic losses do add up though: typically 3-5% might be lost in the wiring and connections, dirt on the modules reduces the amount of light reaching the cells, manufacturing variations between modules (called module "mismatch"), seasonal sun-angle changes, operating temperature (hot on a roof in the sun) and other factors reduce the total output of the system.

      Additionally, as the modules age they lose some efficiency. This is sometimes stated to be typically as much as 0.5% per year, although some studies show loses to be as little as 0.1%/year. Here's a good study:

        http://www.pv-magazine.com/...

      When designing PV grid-intertie systems (without battery storage), we typical use a 0.77 to 0.80 multiplier of the STC PV array wattage rating, so we are figuring on a 20-23% systemic loss from the array STC rating over the 25-year expected life of the system.

      Battery based systems (used in off-grid or emergency backup systems) have greater losses, due to battery efficiency losses in the charge/discharge cycle, and the fact that battery-based inverters also have to invert the lower voltage of the battery (typically 48 VDC in residential systems) into higher voltage AC, and battery self-discharge losses. Battery-based inverter are a lot more complex and therefore have greater losses.

      Now, as far as power distribution losses are concerned, there are a lot of variables. Energy produced by your rooftop PV array will first be consumed by any electrical loads that are running in the building they are on. Electricity will always take the path of least resistance, so loads in the building will draw that power before pushing any excess onto the grid. Loses in the house wiring, and the efficiency of appliances, will be common whether you use solar of grid power, so shouldn't be considered here. Losses through the grid are also incurred no matter how or where the energy is produced, although since daytime loads are essentially powered by the PV on-site, those losses are not applicable to daytime loads at or below the amount of power produced by the PV system.

      All of this is really just academic though. Assuming there is enough physical sunny space available, a PV system can be designed and installed to provide 100% of the required energy consumption at the site, no matter what the systemic losses are. It takes about 2-3 years of operation for a PV system (batteryless) to make back the energy it took to manufacture, ship, and install the components, and they will last at least 20 years, so there is certainly an energy gain. Inverters and wiring will fail and require replacement long before the PV modules are no longer effectively useful, and in fact most long-term economic analysis figures on inverter replacement in 15-20 years. I have a set of 32 year-old PV modules that are still going strong.

      "If you lose your sense of humor, it's just not funny anymore" Wavy Gravy

      by offgrid on Sat Jun 21, 2014 at 11:16:56 AM PDT

      [ Parent ]

      •  Thanks for the detailed response! (0+ / 0-)

        What technology is used to convert DC to AC (as opposed to the step up part which a transformer takes care of)? Solid state or mechanical switches?

        "Reagan's dead, and he was a lousy president" -- Keith Olbermann 4/22/09

        by kovie on Sat Jun 21, 2014 at 03:10:08 PM PDT

        [ Parent ]

        •  All solid state (1+ / 0-)
          Recommended by:
          kovie

          at least these days.

          Most smaller inverters for residential and small commercial applications use FETs (field-effect transistors), usually in what's called an "H-Bridge" configuration. Combinations of FETs switching on and off in variable patterns create a digital approximation of a sine-wave AC voltage.

          Larger, more complex and more costly inverters use IGBT (Insulated Gate Bipolar Transistors) because they can handle higher power outputs efficiently.

          When I started playing with solid-state inverters back in the 80's, they had lousy power quality and were not very reliable. That's one reason why most off-grid houses (there was no such thing as grid-connected solar back then) used DC directly as much as possible. If the inverter broke down, at least you had lights and a fridge, even if you couldn't watch TV, vacuum the house or run the blender. Inverter technology, quality, and reliability have greatly advanced in the past 20 years. In fact I have designed and sold inverter systems for use in music recording studios because of their quality power output. The output power quality of modern inverters make typical grid power look sick.

          I did once have and use a mechanical inverter made by Honeywell in the 70's. It used a brush-type 12V DC motor to spin a 120V AC alternator. Only 400W, and horribly inefficient (about 40% efficient), but it did have very nice true sine-wave power, although the frequency (hertz) varied based on battery voltage. They were used in ambulances and other energency vehicles at the time.

          "If you lose your sense of humor, it's just not funny anymore" Wavy Gravy

          by offgrid on Sat Jun 21, 2014 at 09:48:21 PM PDT

          [ Parent ]

          •  Do mechanicals use what's known as a breakwheel? (0+ / 0-)

            I was reading about those in a bio of Tesla recently. I've been tinkering with electronics lately, nothing fancy, just the basics, but designing and building a low-power inverter seemed like a fun project, and I figured that transistors and some sort of RCL circuit was one way to do it. I could probably even put together a very crude one with a 555 and some BJT's and caps.

            This started out as a way to show my young nephews some basic electronics, but I've gotten hooked. I did some very basic tinkering in my youth and took a few classes in analog and digital electronics in college, so it's also a way of reconnecting with long gone times. And given that our world utterly depends on electronics (and I have an engineering background), I thought it would be nice to have some idea of how it all works.

            Thanks again for the detailed and useful responses.

            "Reagan's dead, and he was a lousy president" -- Keith Olbermann 4/22/09

            by kovie on Sat Jun 21, 2014 at 10:00:39 PM PDT

            [ Parent ]

  •  Could someone give a short explanation of (1+ / 0-)
    Recommended by:
    nzanne

    what all of those possibilities

    Is the Earth's turbulent magnetic field weakening, moving, or about to flip?
    could mean for all of us and our lovely little besieged planet.

    I think "flipping" would probably be the worst, but "moving" sounds bad too. And "weakening," not sure of the consequences. The original article and visualization are cool, but I don't understand what any of the results would be.

    this is something from NASA's IMAGE, but not much

    If the magnetic field of the Earth suddenly changed, and this DOES happen naturally every 250,000 years or so, the consequences would be fascinating. For life, we can see from the fossil record that the past field changes had no significant effect on living organisms. This is most curious because the field reversal ( North magnetic pole shifting to antarctica and the South magnetic pole shifting to the arctic region in the Northern Hemisphere) one might expect the field to go to zero strength for a century or so. This would let cosmic rays freely penetrate to the Earth's surface and cause mutations. This seems not to have had much effect in the past, so we probably don't really know what is going on during these field reversals. There have been a dozen of them over the last few million years, documented in the rock which has emerged and solidified along the mid-Atlantic Ridge where continental plates are slowly separating. These epochs form parallel bands all long the ridge where the rock has stored a fossilized image of the local orientation of the Earth's magnetic field for the last few million years.
    more for K-12 teachers here.
    •  Don't worry, it takes a long time for the magnetic (1+ / 0-)
      Recommended by:
      Just Bob

      pole to reverse. "Suddenly" is only in geological time, say thousands of years.

      It's actually more like every 500,000 years that it reverses.

      The last time it happened was about 750,000 years ago. So, we are over due.

      "If you don't sin, then Jesus died for nothing!" (on a sign at a Mardi Gras parade in New Orleans)

      by ranger995 on Sat Jun 21, 2014 at 07:14:07 AM PDT

      [ Parent ]

    •  I can already hear climate denialists using (0+ / 0-)

      this as an excuse. I'm sure climate scientists have investigated this possibility for climate change..does anyone have a link to such research?

  •  I shot this image 2 weeks ago, in Monaco (6+ / 0-)

    Self explanatory

    P1040826

    I just want to live somewhere warm. Is that so wrong?

    by lotac on Sat Jun 21, 2014 at 06:59:35 AM PDT

    •  Europe and Asia have electric bikes now (3+ / 0-)
      Recommended by:
      lotac, ranger995, BlackSheep1

      Don't look to Harley for an electric bike. They don't even develop products--the corporation makes more money licensing their "brand" than making motorcycles. They are the last to adopt technology as it comes into production. My bike has ABS, fuel injection, catalytic converter, tubeless radials (on spoked wheels), etc, and it's nearly twenty years old. Not a Harley.

      •  Asia and Europe have a couple scooters (2+ / 0-)
        Recommended by:
        ranger995, lotac

        Currently, and for the forseeable future, only the US produces electric motorcycles. Brammo, Zero, Mission, BRD and Lightning are all American companies. Yamaha may be coming out with something in a year or two, probably around the same time Harley does.

        BMW and a few others have electric scooters, but nothing remarkable really. Right now, batteries are too expensive for e-bikes to gain as much traction as an electric car. Look at the Zero, if it were an ICE with those specs and components, it would cost maybe $5,000, but those things are well north of $15,000, solely because of the batteries. For most, it's just not worth it.

        First they came for the farm workers, and I said nothing.

        by Hannibal on Sat Jun 21, 2014 at 07:45:34 AM PDT

        [ Parent ]

  •  Electric Motorcycle (1+ / 0-)
    Recommended by:
    offgrid

    The only bummer is that there will be no more changing gears. That's a big part of the experience for me that I will have to get over. For no emissions, I guess I can do it.

    "If you don't sin, then Jesus died for nothing!" (on a sign at a Mardi Gras parade in New Orleans)

    by ranger995 on Sat Jun 21, 2014 at 07:11:29 AM PDT

  •  I *like* that Harley (1+ / 0-)
    Recommended by:
    BlackSheep1

    90 miles round trip to an from work each day for less than a dollar speaks to me.

    Every day, I get up and pray to Jah . . take the skinheads bowling . . take them bowling . .

    by thenekkidtruth on Sat Jun 21, 2014 at 07:39:51 AM PDT

  •  the Internal Combustion Engine is dying (1+ / 0-)
    Recommended by:
    offgrid

    the Rise of the EV is inexorable now.

  •  Maybe not... (0+ / 0-)

    Most of the bikers who live around my apartment here in SF like their bikes REALLY loud and obnoxious.  I'm sure Electric won't do for them... Not Obnoxious enough.

  •  let 'em go for pinks against a nice (0+ / 0-)

    quiet CBX (yeah, 30-odd-year-old Honda tech).

    (It does sound like an F-4 Phantom when you wind it out. I like my obnoxious noises fast).

    LBJ, Van Cliburn, Ike, Wendy Davis, Lady Bird, Ann Richards, Barbara Jordan, Molly Ivins, Sully Sullenburger, Drew Brees: Texas is NO Bush League!

    by BlackSheep1 on Sat Jun 21, 2014 at 09:48:33 AM PDT

  •  GoT, GoT (1+ / 0-)
    Recommended by:
    rduran

    I am so bloody sick of Game of Thrones.  

    And the evolution of Neanderthal facial features has nothing to do with Game of Thrones.  Comparing their polyphyletic ancestry to the dynastic history of fictional Westeros doesn't shed light on anything; that's just dropping names to get media attention.

    Pop-culture media suck-ups.

    I've lost my faith in nihilism

    by grumpynerd on Sat Jun 21, 2014 at 10:29:07 AM PDT

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