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Power Transportation Technology

Inductive Charging For EVs To Be Tested In Berlin 123

cylonlover writes "The increasing availability of more practical electric vehicles has seen inductive charging technology attract the attention of those looking for for a cable-free way to charge EV batteries. German automakers are taking the opportunity to put inductive charging of EVs to a real-world test as part of the 'Effizienzhaus-Plus mit Elektromobilität' project. The project is a German government-backed initiative to build an energy-efficient house that generates more electricity than it consumes, with the surplus being fed back into the grid or used to charge the occupants' electric vehicles."
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Inductive Charging For EVs To Be Tested In Berlin

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  • Low efficiency? (Score:5, Insightful)

    by eparker05 ( 1738842 ) on Wednesday December 21, 2011 @06:43PM (#38454248)

    I suppose when you only need a few watts of energy for a cellphone or something, I can understand the use of inductive charging. But if you lower your efficiency by a significant amount in a single step while charging a car (a few dozen kWh), and this is multiplied across a population of EV owning people, this is potentially adding a lot of unnecessary strain to the electric grid.

    Is it so hard just to plug the dang thing in? We don't have tubeless fuel transfer do we?

    • If you spill a little gasoline when filling your tank, it's not a big deal. If you spill a little electricity when charging your battery, it's more of a deal. Think of your grandma trying to plug a giant 300A cable into her car, or someone trying to do it while on his phone and drinking a cup of coffee.
      • Re:Low efficiency? (Score:5, Insightful)

        by eparker05 ( 1738842 ) on Wednesday December 21, 2011 @07:17PM (#38454542)

        Actually, spilt gasoline is a big deal. Aside from it's detrimental effects on the environment, it's also has mildly toxic fumes and it is highly flammable. Every year many people are burned while pumping gas, we just don't hear about it much because, like car accidents, it is one of those risks that we just accept.

        As for 'grandma' using a 300 amp plug. I think a clever engineer could come up with a relatively safe plug that doesn't sacrifice as much efficiency as inductive charging does.

        • Re: (Score:3, Insightful)

          by Endlisnis ( 208453 )
          If you spill a *little* gasoline, it's not a big deal, to the person pumping the gas. Yes, I'm sure that many people are horribly burned from pumping gasoline while trying to light a cigarette every year, and you are never going to have a perfect system. But I could pretty easily (if I wanted to), go to a gas station, accidentally pump gas all over my pants and walk away uninjured, assuming I didn't do something stupid afterwards like try to dry myself off by a campfire. But if I tried the same thing wit
          • Re:Low efficiency? (Score:5, Insightful)

            by Draconmythica ( 1057150 ) on Wednesday December 21, 2011 @07:41PM (#38454772)
            You simply need to include a low voltage "handshake" type setup in the charging circuit and then only start the high power transfer once the plug is fully engaged. This shouldn't be too hard to implement for even a mildly clever engineer totally removes that risk.
            • Re:Low efficiency? (Score:4, Informative)

              by sexconker ( 1179573 ) on Wednesday December 21, 2011 @08:17PM (#38455058)

              You simply need to include a low voltage "handshake" type setup in the charging circuit and then only start the high power transfer once the plug is fully engaged. This shouldn't be too hard to implement for even a mildly clever engineer totally removes that risk.

              That "handshake" is called a ground connection.
              Many plugs have conductors of different lengths. The longer connectors are the ones you want to engage first.

              Typically, the ground connectors engage first as you plug the cord in, so the device has a place to shunt current to in case of an OH SHIT moment.
              Then your other, shorter connectors make contact as you continue pushing the plug in. If something's wrong with the device or those connectors, you already have a path to ground.

              I think the SATA power connectors play this game with the +3.3V and +5V lines too. Not sure.
              Look at the connectors on an SD card. Same principle.

              • by swalve ( 1980968 )
                If it is inductive, there is no ground.
                • If it is inductive, there is no ground.

                  If it's a parked vehicle on a designated "Inductive Charging Spot!(TM)", then the charging installation obviously has a path to ground, and the vehicle can easily have one too. The weight of the vehicle can trigger a small conductor to rise from the charging station and touch the vehicle. The vehicle can have a tail.

                  It's not rocket science - we have electric vehicles that are grounded and charge while we let children drive them. Bumper cars.
                  We also have automated car washes where people slowly drive thei

          • But I could pretty easily (if I wanted to), go to a gas station, accidentally pump gas all over my pants and walk away uninjured,

            This is not actually true.

            Gasoline is only really "safe" to spill on yourself because it generally evaporates quickly - far faster then it can be absorbed by the skin (hence the "cool" feeling if you do happen to do this). This only holds true if the quantity remains small though, and it's not absorbed into something - like your pants.

            It would be a supremely bad idea to continue wearing pants that have absorbed a significant quantity of gasoline and then just waiting for them to dry out. Yes you're "uninjur

        • I think the EV1 actually used a plug that was a paddle that slipped into a slot on the hood. But I believe it actually charged via induction, so it wasn't actually a plug in the traditional sense, and I'm not sure how efficient it was.
      • Re:Low efficiency? (Score:5, Interesting)

        by uncqual ( 836337 ) on Wednesday December 21, 2011 @07:54PM (#38454894)
        I don't follow charging plug technology/standards. However if "spilling electricity" is a problem, it seems that something very wrong has happened in the standards process for these plugs. (The size/weight of a 300A cable for a very weak person might be more of a problem, although it seems like even that could be addressed by fairly simple mechanical systems to counterbalance the weight.)

        Presumably (I certainly hope!) the charging stations have GFCI protection to prevent injury/damage from some of the common screwups/failures (fault to ground through human being a particularly interesting one).

        A firm verified locking engagement of the cable and car presumably (again, I certainly hope) is required before power is enabled and breaking that locked engagement presumably shuts off the power.

        For extra credit, if the charging unit and the vehicle being charged ever disagree substantially on the amount of energy being transferred (due, for example, to a breakdown somewhere in the cable causing a short across positive/negative which would not be detected by GFCI but could lead to fire problems et al), the charger should presumably shut down (this might not be a very precise safety mechanism due to having to allow for varying resistances of cables/cars).

        For super extra credit, provide a standard mechanism to allow a car to identify itself though the plug via a cryptographically secure mechanism (similar to smart card). This would facilitate employers, for example, allowing employees to recharge their registered cars for free with a minimum of hassle without opening the recharging up to everyone in the parking lot. It would also allow cardless recharging at commercial recharging stations -- just plug into a charging station that is on the ShellCharge network and your car is instantly recognized and you're billed as appropriate. It would also allow a multifamily dwelling complex to provide chargers in a very transparent fashion to their residents.
        • Re: (Score:2, Insightful)

          by sexconker ( 1179573 )

          For super extra credit, provide a standard mechanism to allow a car to identify itself though the plug via a cryptographically secure mechanism (similar to smart card). This would facilitate employers, for example, allowing employees to recharge their registered cars for free with a minimum of hassle without opening the recharging up to everyone in the parking lot. It would also allow cardless recharging at commercial recharging stations -- just plug into a charging station that is on the ShellCharge network and your car is instantly recognized and you're billed as appropriate. It would also allow a multifamily dwelling complex to provide chargers in a very transparent fashion to their residents.

          Holy shit a good idea on Slashdot.
          Apartment complexes (and the shitty housing market making them necessary for more and more people) are one of the big things holding back plug-in cars.
          If people can't plug their car in they're not gonna buy a plug-in car.

          • by Anonymous Coward

            Yes, that really appealed to the engineer in me. Then the cynic in me tapped my shoulder and said that the real use for that system would be vendor lock-in.

            Think printer cartridges, except in this case they will say they are doing it for public safety.

          • by whois ( 27479 )

            There's no reason your car can't send signaling through the inductive system and do the same identification. I'm mainly concerned about efficiency concerns, but if they find a way to make it work then it opens up a bunch of other practical uses (the drawbacks being living and working forever in giant EM fields, but again they have problems to solve..)

      • For God's sake, how hard can it be to install a RCD in the things, as soon as the current goes somewhere it shouldn't, it's shutdown and the dumb user the standing there until the garage guy comes out to help after seeing an error on his panel.
    • by pjwhite ( 18503 )

      The answer to this question is, "convenience."
      Imagine the scenario where you recharge your commuter car overnight. With a plug system, you will have to remember to 1) plug in the system when you get home and 2) unplug it again when you leave for work the next day. If you forget either of these steps, you end up with either an uncharged car in the morning, or the plug gets ripped out of the side of the car when you drive off.
      If you can drive over an inductive loop when you park, your car will charge automa

      • by Anonymous Coward

        It would be trivial to put in an interlock that prevented the car from moving when it was physically plugged in.

      • by jafac ( 1449 )

        Yeah; but the "convenience" issue for electric cars is:
        typical non-workday use-case: I would like to drive up to Yakima to visit my Sister's family this weekend @ 500 miles.
        EV car has 250 mile range on freeway + 8hr recharge between 250 mile sprint. . . therefore, 500 miles will take (50mph freeway avg. . . 5hr + 8hr charge + 5hr =) 18 hrs, each way. . .
        Gas car has - we'll say 250 mile range on freeway + 10 minute refuel stop: (my diesel car has a 450 mile range on freeway, so suck-it). ETA 10 hr each way.

        • Your "typical non-workday use-case" is ridiculously UN-typical for most people.

          Plus, why can't you have 2 cars (you probably already do?).. one for daily usage, electric, and a gas (or better, hybrid) one for weekends?

        • by swalve ( 1980968 )
          Electric vehicles aren't for everyone, the same way a garbage truck or a motorbike isn't for everyone.
        • Is it so hard to buy a generator trailer with the car? They could even make it a turbine of some kind, or some super efficient gas engine. Some of the cars have this option, so I couldn't be the only one to think of it.

      • by Jmc23 ( 2353706 )
        Canadians have done it for decades without any problem, are USians just lazy or what? Lot's of cars here come with plugs and lots of parking spaces have outlets to plug into to heat up the engine block.
      • 1) The Leaf can text you if it hasn't been plugged in by a certain time. I've never used the feature as I have to walk past the charger to get into the house. Not plugging it in requires a conscious decision not to do so. Otherwise it's "put it in park, flip the plug door, get out and plug it in as I walk toward the door to the house". It's literally an extra five seconds out of my day.

        2) The Leaf won't "start" if it's still plugged in. Or so I've been told. *cough*.

        I'm sure there are some use cases I'm mis

  • by Urza9814 ( 883915 ) on Wednesday December 21, 2011 @06:50PM (#38454312)

    Who's the idiot who decided to put 'inductive charging' and 'energy-efficient' in the same paragraph? If you're trying to be efficient, inductive charging is the LAST thing you want to do. If you really are that opposed to having to plug in, come up with some innovative solution using contacts embedded in the garage like cordless phone cradles. Or do something like bumper cars. Though I bet people wouldn't like the thought of having exposed high voltage contacts...but I'm sure they could figure out a way to make it safe. Hell, even a plug on the front of the car that drives into a receptacle. Inductive is just stupid.

    • OK, ill bite.

      Inductive charging is not energy-efficient.

      Who is the idiot now?

    • by swalve ( 1980968 )
      There is no doubt a transformer somewhere in the EV car charging path. Just make that the inductive connection.
      • Still not going to be as efficient as a direct connection. A normal transformer is going to be far more efficient than an inductive charger. It's not going to use air between the coils, it's going to be insulated, etc. All those improve efficiency. A power transformer will likely be more than 98% efficient, while an induction transformer is likely around 86%. And I would imagine this inductive charge system will be less efficient than those currently on the market -- if you're inductive charging a cell phon

  • Inefficient (Score:4, Informative)

    by Redbaran ( 918344 ) on Wednesday December 21, 2011 @06:51PM (#38454330)
    Wikipedia cites an 86% efficiency for inductive charging. I would bet that efficiency is hurt as this scales up from a cell phone to a car. Other than helping to improve EV adoption by making it more convenient, why would we want such a system?

    Given the current costs of an EV, plus the length of time it already takes to charge, it seems there are other areas of research that would be better focused on. This technology only makes an EV more expensive to own and would probably take longer to charge with. People seem to do just fine connecting a short, thick, clunky hose to their cars now.

    (http://en.wikipedia.org/wiki/Inductive_charging#Disadvantages)
    • Re:Inefficient (Score:4, Insightful)

      by Anonymous Coward on Wednesday December 21, 2011 @06:58PM (#38454404)

      You would be incorrect on your assumption. Inductive energy transmission efficiency involves many factors, but as voltage and current raise, recapture losses begin to drop off. Again MANY factors are involved here, but the base assumption that scaling inductive energy transmission up decreases efficiency is false.

    • Re: (Score:1, Redundant)

      by CanHasDIY ( 1672858 )

      Wikipedia cites an 86% efficiency for inductive charging.

      Gasoline engine [wikipedia.org] efficiency is typically between 25-30%; Diesel engines [wikipedia.org] do a little better, at between 40-50% efficiency. That said, the 86% efficiency rate of EV's is still over 30% greater than that of the most efficient internal combustion vehicles... and that's not good enough?

      • Re:Inefficient (Score:4, Insightful)

        by Anonymous Coward on Wednesday December 21, 2011 @07:09PM (#38454486)

        Wikipedia cites an 86% efficiency for inductive charging.

        Gasoline engine [wikipedia.org] efficiency is typically between 25-30%; Diesel engines [wikipedia.org] do a little better, at between 40-50% efficiency. That said, the 86% efficiency rate of EV's is still over 30% greater than that of the most efficient internal combustion vehicles... and that's not good enough?

        This is only for the charging. The actual production of the electrical power has additional losses.

        • by Anonymous Coward

          The actual production of the electrical power

          Don't forget transmission and the conversion of electrical power into actual momentum. I wonder how efficient inductively charged electrical cars would be when you take in all those losses?

          • Modern electric motors can be almost 99% efficient at turning electrical energy into mechanical energy.

        • Wikipedia cites an 86% efficiency for inductive charging.

          Gasoline engine [wikipedia.org] efficiency is typically between 25-30%; Diesel engines [wikipedia.org] do a little better, at between 40-50% efficiency. That said, the 86% efficiency rate of EV's is still over 30% greater than that of the most efficient internal combustion vehicles... and that's not good enough?

          This is only for the charging. The actual production of the electrical power has additional losses.

          According to the government [fueleconomy.gov], "Electric motors convert 75% of the chemical energy from the batteries to power the wheels—internal combustion engines (ICEs) only convert 20% of the energy stored in gasoline."

          IANA electrical engineer, but 86% fueling efficiency + 75% fuel-usage efficiency sounds like it should blow 50% fuel-usage efficiency away any day of the week.

          Though, I expect an electrical engineer to be able to correct my admittedly pitiful math if I'm wrong...

          • Re:Inefficient (Score:5, Insightful)

            by Tanktalus ( 794810 ) on Wednesday December 21, 2011 @07:47PM (#38454826) Journal

            I took EE in school. Many years ago. Haven't done a thing with it since. However, the part you seem to be missing (and the AC you responded to) is simple logic, not EE-specific. We're not comparing inductive charging to gas vehicles. We're comparing inductive charging to non-inductive charging. That is, driving your EV to a specific area of your garage vs driving your EV to somewhere that it can reach the proper outlet and be plugged in.

            86% efficiency for inductive charging means that when you buy 1KWh from the power company, you're only getting .86KWh to your vehicle. Additional losses come into play after that (and before that as well), but they should be the same losses whether we're using inductive charging or not, so they're entirely irrelevant. Copper wire's losses are negligible over this short of a distance, so when you buy 1KWh from the power company, you're putting 1KWh of energy into your vehicle, for all intents and purposes. That 14% loss is increasing the cost of "refueling" your EV by about 16%.

            When comparing against gas vehicles, the mode of charging is relevant in that it affects the overall efficiency of the system. And you have a valid point that the overall efficiency of an EV likely far surpasses gas and diesel vehicles. However, we then open whole new cans of worms - depending on your energy source, the EV may not be a significant overall improvement when considering things like pollution. If your electricity is from a coal-fired plant vs natural gas vs nuclear/wind/solar/hydro, for example. If from coal, the EV advantage may not be nearly as significant.

            Having said all that, induction charging can make the convenience of an EV very attractive. You don't have to think about it, you have a fully-charged vehicle every morning. No worrying about making a run to the gas station for regular commutes. If someone else can solve the distance problem, we could get a long way toward a serious contender to take gas vehicles off the road. While this doesn't make the EV a must-have, it is another parallel attempt to get there.

        • To explain further: this would be like saying that when filling up at the pump, only 86% of the gasoline makes it from the pump to your gas tank, and the rest is lost in the transfer.

          Of course, direct contact also has losses during charging, so I'd like to see a direct comparison with measurable numbers. If this is on TOP of the losses already accrued due to charging... well....

        • How much energy does it take to refine gasoline? You are comparing apples to oranges, stop it.

      • I don't really care that much, and I'm sure most other people feel the same, about how energy efficient or not a particular source of fuel is. I care more about how much $ per mile, how far I can go, and how fast to refuel. I don't even know the first thing about inductive charging, but if means I can travel to work and back for a few dollars or cross country for a few hundred bucks, refuel in minutes not hours, then it sounds good. Oh, and if I'm stuck in a winter storm in Chicago for 12 hours in my car as
        • I don't really care that much, and I'm sure most other people feel the same, about how energy efficient or not a particular source of fuel is. I care more about how much $ per mile, how far I can go, and how fast to refuel. I don't even know the first thing about inductive charging, but if means I can travel to work and back for a few dollars or cross country for a few hundred bucks, refuel in minutes not hours, then it sounds good. Oh, and if I'm stuck in a winter storm in Chicago for 12 hours in my car as many were last winter, will it keep me warm?

          Ultimately, those concerns will be the deciding factors in whether EV's manage to surpass ICEV's any time in the foreseeable future.

          They (EV's) lost that battle in the 1920's, and even though batteries have become orders of magnitude more efficient than those of yesteryear, I personally don't see the EV replacing the good-ol'-fashioned inefficient, heat producing internal combustion engine anytime soon.

          • Replacing... mm perhaps not. But I think that relegating it to backup-status for now will be common. Sort of like sails on ships. When they switched from sails to steam power, they kept them for backup for a long time. If it is only needed to provide electricity, you can tune it much better than when it needs to provide power to the wheels.

            • Replacing... mm perhaps not. But I think that relegating it to backup-status for now will be common... If it is only needed to provide electricity, you can tune it much better than when it needs to provide power to the wheels.

              Very true.

              Now, if only someone could figure out a way to build such a system inexpensively... oh wait, someone did - 32 years ago. [motherearthnews.com]

        • Well, considering the inductive charging station is a permanent installation at your home, work, or other building. It will not affect an EV's ability to keep you warm at all. That is an electric heat / battery problem which is a different thing entirely from how the battery gets charged.

          /. is notorious for dismissing the benefits of convenience and ease of use if the specs are not as good. "No wireless. Less space than a nomad. Lame."
      • by Anonymous Coward

        Those numbers refer to the efficiency of turning the energy in the fuel into mechanical energy needed to operate the engine, not to recharge it. I'm pretty sure recharging a liquid fuel engine is around 99% efficient (a little bit always spills out).

    • by Jeremi ( 14640 )

      Other than helping to improve EV adoption by making it more convenient, why would we want such a system?

      Convenience is the only reason. You have to admit, having your car automatically charge itself without you ever having even to think about it would be pretty cool.

      The downside is the inefficiency, of course. Maybe someone clever will come up with a way to boost the efficiency to the point where it's no longer an issue -- or maybe they won't, and frugal-minded people will plug their car in, instead. Either way is okay with me.

    • 86% is your typical switch-mode efficiency. Some reach in to the low 90's with synchronous rectification but the main thing is that all chargers have to translate voltages, ie: Plug-in versions do the inductive voltage translation internally.

      Using superconductors for the inductor windings would improve it.

  • As a RealGeek(tm), I'm fascinated by this report and its possibilities. But I wonder why fluffs like Facebook are valued billions more valuable than something useful like this. Not that there's anything wrong with Geeking to make said billions -- this is a criticism of the customer base.
  • Problem? (Score:5, Funny)

    by elsurexiste ( 1758620 ) on Wednesday December 21, 2011 @07:01PM (#38454420) Journal

    The project is a German government-backed initiative to build an energy-efficient house that generates more electricity than it consumes

    Problem, thermodynamics?

    • The project is a German government-backed initiative to build an energy-efficient house that generates more electricity than it consumes

      Problem, thermodynamics?

      Problem, comprehension? If the house has solar panels, wind turbines, etc, as well as being energy efficient in usage, then yeah, it could easily generate more electricity than it produces. You know, like a power plant.

      • Re: (Score:3, Interesting)

        Problem, comprehension? If the house has solar panels, wind turbines, etc, as well as being energy efficient in usage, then yeah, it could easily generate more electricity than it produces. You know, like a power plant.

        Problem, engineering? Even if the house has solar panels (optimistically 20W/sqft cite [yahoo.com]), wind turbines (in a heavily suburban area with trees, neighbors, kids who like throwing things into other things... cite [energybulletin.net] = maybe 200kwH per year), etc., as well as being energy efficient in usage...

        Okay, let's just stop there. Your fridge alone needs 600kwh. Hate to break it to you, but unless you live in a temperate climate that requires no heating, cooling, and the only major appliance in your house is a fridge, forg

        • I had assumed (very dangerous, I know) that the EV would be charged at night at low rates, then fed into the system during the day at high rates, thus taking care of the dollar value of the remaining electricity the house needs. Or sell it and the generated electricity back into the grid at peak times. Not a net plus in energy usage, but in dollars spent on energy usage. I haven't checked their numbers, so I could be wrong.

          I would also expect that they're going to be using very efficient appliances in this

        • This may be of interest: http://hypertextbook.com/facts/2003/BoiLu.shtml [hypertextbook.com]

          If it is possible to design a house that only consumes http://www.hollowtop.com/cls_html/solar_power.htm - gives them 2500 kWh/year. Uses a bit of real estate but we can get more efficient cells and then the price goes up but you can certainly get more power than this. And it is more than enough if you designed your house the right way. Even without a lot of measures, the average energy use for a Dutch household (2.1 persons) is around

        • The US DOE estimates a fridge uses 725W source [energysavers.gov]. Lets say they have 1000 ft^2 of roof space that is all solar panels. That would provide ~20,000W with your number of 20W/ft^2 (this is highly variable though). Looks to me like that house could have 27.5 fridges running off of those solar panels. That's definitely better than you suggest.
        • Re:Problem? (Score:5, Insightful)

          by aXis100 ( 690904 ) on Wednesday December 21, 2011 @09:12PM (#38455414)

          Problem, bad info??

          My pissy little 2.2kW solar system, consuming maybe 1/10 of my roof space, has generated over 1400kWh since August. I've cut my daily import consumption by more than half - from 20kWh to 9kWh - and that's still using airconditioning, two fridges, multiple PC's running all day and an electric tumble drier.

          A bigger solar system or better engineered house with specific attention to energy efficiency would blow my efforts out of the water and easily have a nett export back to the grid.

          • How much did yours cost, and what do you think the "payback time" will be?

            (Disclaimer: I actually think payback time is often not a great question to ask.. one can want to be green even if it's more expensive... just like driving a ridiculous expensive BMW instead of a Civic.)

        • Re: (Score:2, Insightful)

          by Khyber ( 864651 )

          Problem, oh non-worker in the field?

          I don't know what outdated fridge you have, but mine consumes on average 300kWh per annum thanks to extremely efficient heat exchangers (the same kind being used in cars, which have typical efficiency of 400% - 1w energy consumed, 4w heat removed from the system.) I also have plenty of low-power and high-power gadgetry in this *HUGE* condo, and I'm still feeding surplus energy into CA's grid from solar and wind. I have a NEGATIVE bill.

          Just because *YOU* use a ton of ineff

          • Do you have a negative bill over the course of a year?

          • by swalve ( 1980968 )
            How do you install solar and wind in a condo?
            • by aix tom ( 902140 )

              By making the suggestion at the owners meeting.

              We have plans to put up thermal collectors when the central heating has to be replaced anyway in 2-3 years.

            • by Khyber ( 864651 )

              Easy - I talk to the owners, show them the facts, show them my technology to go with it to make it really work out, and they go "Nice! Let's do that, we'll drop your rent!"

        • by lorinc ( 2470890 )
          Maybe you didn't know this, but not every country in the world is as energy hungry as the US. Just sayin'...
        • Someone who cares about these things isn't going to get an 600kWh / year fridge. He is going to get a A+++ 161 kWh / year fridge freezer combo [liebherr.com] Maybe a second fridge to plug in in case of a party.
        • Do yourself a favour and get rid of your shitty fridge. Even an average modern one (kike Bauknecht KG335) needs only around 240 kWh per year, better ones (like Siemens KG39EAW40) are satisfied with 160 kWh or less.

        • Did you forget that there are many hours in a year, and multiple square feet on a roof?

      • When I read the summary, it sounded a lot like troll physics, hence the joke. But I'll get serious now.

        I friend of mine studied/worked on alternative energies, and he told me that, at a small scale (houses) the efficiency is too low to make great economic sense. There are a few designs that are cheap and useful, but nothing fancy like electricity from solar or wind. What the Germans are trying to do requires a lot of planning and design, and in any case it won't "easily generate". Just look at the car in th [bmvbs.de]

        • by Jeremi ( 14640 )

          We are still at least a decade away from economically sensible solar and wind (for individual homes, at least).

          That all depends on how you define "economically sensible", which itself depends on what the alternatives are.

          Where I live (in Pasadena, Southern California) the price of residential grid power is 15.5 cents per kWh. Our solar array (which is owned by a third party who we purchase power from), OTOH, provides us with power for 9.5 cents per kWh. So for us, solar power is already the cheaper option.

          Granted, the 9.5c/kWh price was made possible by government subsidies, but if there had been no subsidies and

  • Who's 'Inductive'?

    and

    Why are they charging for EVs to be tested in Berlin?

  • by NoobixCube ( 1133473 ) on Wednesday December 21, 2011 @07:17PM (#38454548) Journal

    People are too stupid to plug their cars in, I mean, connecting something to the car to make it go? It just baffles the mind! That's why we all fuel up by driving into a pool of petrol and letting osmosis take its course!

  • They should just build that stuff into the roads so we can drive our cars like bumper cars. Charge while you drive.
    • This occurred to me too, but the caveats are overwhelming. At first, I thought, if they just ran power lines through the road rather than up on poles, with some modifications, this would be cool. But doing it on the scale necessary, like Interstate highways or state routes, would be insanely expensive, not to mention the issues of possible radiation and what typical road wear and tear would do to the lines. Plowing snow, forget it... Sounds good "on paper" though.
  • That is the real interesting part. Simply park your car in the required spot and the house can pull back electricity if needed, or even sell it back on the market if allowed (and at a higher price).
  • They're trying this out with some electric buses in Chattanooga, Tennessee: CARTA's electric buses to charge on the go [timesfreepress.com]

  • by Anonymous Coward

    nissan leaf inductive charging pad is available as an extra here in japan.

    just roll over it in the garage and go about your buisness...

  • by Anonymous Coward

    Why don't they just embed the charging station in the ground? Electric car pulls into parking space, once turned off it lowers a contact panel to the ground and sends a few low voltage wake signals to the charging station. Charging station wakes up determines which of the small charging panels the wake signal came from and then begins to charge the battery. Heck if you wanted to get fancy you could even add more communication between the car and the charging station so the charging stations knows what the c

    • The rules here in the Netherlands would probably forbid it, since the contact is powered when the car is charging and during that time the contact can be touched, eliminating the stupid genes out of the gene pool in the best case, roasting a kid that dropped a ball under the car in the worst case.
      There are ideas about a robotic arm with a connector.
      • You could configure the under-side of the car to have a grid of potential electrical contacts, and once the panel raised up the car would negotiate which ones it was actually connected to, and only engage them. If the mating was flush (or slightly recessed) then it wouldn't be possible to touch them.

  • 1) It's convenient.

    2) It's cool.

    Reasons not to do this:

    1) 86% efficiency for a load of 10's of kW stinks. For 10kW input power, I get 8.6kW into the car. The missing 1.4kW heats the garage. Note that the efficiency could probably be improved, but this would cost more, and be bigger.

    2) It will add a lot of cost. Are you willing to pay a couple of extra $k for this?

    3) It has EMI and safety issues galore. You don't want to accidentally dump a few kilowatts into your kid's trike, or your lawn mower. T

  • Swap the batteries for goodness sake!

    - make it easier to swap the batteries!

    1) The phyisical process of changing batteries needs to be easier
    2) The possible trade of poor quality batteries for good quality needs to be addressed

    ^ these are more organisation issues than technical. If you have an EV you can already set this up yourself for a regular long journey to work. You stow your batteries along the route with people who charge them for you for a fee.

    Unfortunately, you have to own a number

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