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Power Hardware

Smart Power Grid Could Wreak Havoc On Itself 331

Posted by Unknown Lamer
from the off-is-the-new-on dept.
MrSeb writes "Smart power grid monitoring that lets you pick the exact cheapest time to run the dishwasher or recharge your electric car may put too much power (so to speak) in the hands of the consumer, according to a new study by MIT. Researchers say that users receiving minute-by-minute pricing information might cycle off-peak power use more rapidly than utilities can spool up their power plants. In other words, it's OK if you're the only person charging your Chevy Volt at 2am in the morning, but if a whole town does it exactly the same time... there will be issues."
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Smart Power Grid Could Wreak Havoc On Itself

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  • by Osgeld (1900440) on Thursday August 04, 2011 @11:35AM (#36987198)

    they will quickly become peak hours, I have the upmost faith in our utilities to gouge us for whatever they can

    • by Abstrackt (609015)

      ... I have the upmost faith in our utilities to gouge us for whatever they can

      That reminds me of a joke about solar power. It will be widely available as soon as power companies figure out how to run a sunbeam through a meter.

    • by Stellian (673475)

      That sounds like a grid that is not smart enough; if everybody charges his Chevy at 2AM, then 2AM will be the new peak hour and it will cost an arm and a leg to charge at that time. If the price information is delayed versus the instantaneous power consumption, then yes, a spike should be expected when the the price drops, but this could be countered by distributing the price information with random delays and only in some areas.

      • by mcgrew (92797) *

        The effect of that would be the same as not having smart grids at all.

        • by h4rr4r (612664)

          No it would not be. The time an appliance started using power would just be staggered. Which is the ideal.

          • True. You'd have power use being very consistent throughout the day, eliminating the existence of peak and off-peak hours, and the potential savings of using off-peak hours. But it would save the power company some money and let law enforcement see exactly what you're running in your house (on the upside, at least they won't raid you for farming Bitcoins or whatever...but can you disguise grow op lights as a server? Hmm...).

            • by mcgrew (92797) *

              but can you disguise grow op lights as a server?

              Some friends of mine solved that problem over ten years ago. A bank of CFLs will put off as much light as a high pressure sodium lamp at 1/5 the wattage, and without having to use the extra electricity to cool the grow room. The weed grew just as fast and was just as tasty and potent as the HPS lamps produced.

        • by GooberToo (74388)

          Not at all. The effect is distributing the load throughout the period which is traditionally considered off-peak.

    • I don't think it necessarily works that way in this case. How many businesses do you know that can just stop using power during peak hours? Office building ACs, for example, during the middle of the day?

      Sure, for actual flexible usage - like people at home doing laundry - you may have a point. But I always thought that the point was to shift home usage from business hours to closer to non-business hours, and especially non-AC hours during the summer.

      Not that "our utilities" aren't trying to make money...

      • Re: (Score:3, Interesting)

        by Osgeld (1900440)

        well I can assure you most places do not shut off their AC when they leave, do you know how much time it takes to get the office back down to 60? (no seriously thats a fad here AC must be 60 so you get a chest cold when you walk in from 103 degree temps, cause little Susie secretary has not spent a day outside since school)

        • by operagost (62405)
          Susie Secretary likes to set the thermostat to 60, then turn on the 1850W space heater under her desk and flip the breaker.
          • by Osgeld (1900440)

            while wearing a sweater (a light sweater but none the less) in fucking August

          • by hawguy (1600213)

            Susie Secretary likes to set the thermostat to 60, then turn on the 1850W space heater under her desk and flip the breaker.

            In my office, Susie Secretary can't control the thermostat (only Facilities can), and since there's limited cooling zones, they have a hard time making everyone comfortable. When Joe Boss with the corner office starts getting afternoon sun through the windows, Susie Secretary outside of his office suffers because the air handlers are sending so much cooling to that zone that it's 67 degrees in her office and 73 degrees in his.

            Sure, it's possible to fix it with a system redesign and maybe some more walls to

        • by jank1887 (815982)

          True, but the systems themselves will (should) run less at night. As the outdoor temperature drops, so does the rate at which the building warms up. Plus you won't have the personnel thermal load, the lighting thermal load, maybe computer equipment thermal load if IT lets them shut down at night, etc.

      • by b0r1s (170449) on Thursday August 04, 2011 @11:52AM (#36987418) Homepage
        You're exactly right ... the power used by businesses far exceeds the amount used by even busy households. Corporate ACs in 20 story buildings use far more electricity than people running appliances at night in their homes. Peak will remain peak, and even in the worst case, 'smart' enough grids should be able to distribute the load across the 'down' cycle, instead of everything running at 2am on the dot.
      • by DarkOx (621550)

        That really depends I would expect lots business DO have some ability to control or at least scale their usage.

        They could say cool the building down to a cooler than normal, but still liveable temperature while power is cheap so they won't need to run cooling as soon or as long during peak later for example. Say crank the place down to 67F between 7 and 8a and then let the place creep up to 74 before you start the AC again during office hours.

        If the cost per kwh is much lower at night, perhaps you do more

    • by iluvcapra (782887)

      Most uses of power during different times of day is obligatory -- you can't schedule all your air conditioning at night, and you can't schedule your lighting for the day.

      In principle, everyone can charge their Volt at 2AM as long as the power company knows ahead of time its going to happen -- the problem TFA posits is that people would be sufficently unpredictable about when they would use their power, or would allocate their power usage in a perfectly rational way in order to minimize their cost per unit,

      • by foobsr (693224)

        people think it will let them pay spot prices for electricity, no no no, ...

        Hard to believe that people can be so naive if confronted with a P_O_W_E_R_ _C_O_M_P_A_N_Y.

        CC.

      • by mcrbids (148650)

        That's what a Smart Grid does -- people think it will let them pay spot prices for electricity, no no no, it's about the power company collecting Google-style metrics of power consumption on an appliance-by-appliance, outlet-by-outlet basis, and then giving you 10% off your bill if you consent to having a remote power cutoff installed on your washing machine, air conditioner, and car charger.

        I'm not aware of there being a definition for what is a "smart grid". It's still evolving, and many people have different ideas about what "smart" grid should be. [betterplace.com]

        All TFA says is that it's easily possible to build a dynamic system that's unstable. Duh. In aviation, the attribute that you are looking for is called "positive dynamic stability" - which simply means that when things get interrupted or jarred, that the system actively works to mitigate the change and stabilize over time.

        This is also something I a

    • Upmost is a b-grade peripherals manufacturer [upmost.com.tw] in Taiwan. I think you meant utmost instead. ;-)

    • Exxactly. I call this the Three Stooges effect (after their gag where they all rush to go through a door at the same time and get stuck). I'm sure you have the same issue with torrents at night in college dorms.

  • by elrous0 (869638) * on Thursday August 04, 2011 @11:36AM (#36987200)

    The big question that seemed/seems lost in all this "The electric car is gonna save the world!" hype is how an energy grid that can barely handle our energy needs AS IT IS is supposed to function when a significant portion of the population replaces their evil petroleum cars with electricity-draining electrics. When I've asked that question in the past to my usual suspect lineup of hippie friends (who also think that organic food and wind turbines are going to save us all too), the only answer I ever got was a vague "Well, most of that'll be happening at night, when the power demand is down anyway." But we're talking HUGE power usage spikes with those cars. Think of how much our system is already taxed when HVAC units have to cool a 10-degree-higher heat wave. Now imagine half the population plugging cars into the gird every night that draw WAY more power than any consumer HVAC unit.

    • by rubycodez (864176)
      oh, we'll have to beef up generation and the grid all right, but that still can be more efficient and cleaner than millions of little fossil fuel burners and the distribution system to feed them
      • by Yaur (1069446)
        Instead of millions of little ones we are just going to have thousands of big ones. Its a step towards a solution but not a solution in and of its self.
    • by RelliK (4466)

      Existing grid can *already* support converting 70% of all the cars to electric, provided that they all charge at night. You really do not appreciate the difference in power usage difference between day and night. Build more power plants & transmission lines and you can get that number even higher. The article is a troll, btw.

    • The big question that seemed/seems lost in all this "The electric car is gonna save the world!" hype is how an energy grid that can barely handle our energy needs AS IT IS is supposed to function when a significant portion of the population replaces their evil petroleum cars with electricity-draining electrics.

      There's plenty of off-peak capacity. The problem arrises when everyone who drove their electric cars to work needs to charge them before they can make the drive home.

      • by geekoid (135745)

        If by 'everyone' you mean people who live more then 50 miles away.
        Companies could have covered parking and use solar to help offesst the peak. Assuming slow charge, you would need about 15 Sqr Meters of panel per car being charge to completely offset it. I am assuming 200watts per sqr meter. And yes, I do realize it won't apply to night shifts.

        That assume they would completely charge the battery, from 0 charge to full. They wouldn't do that. It would be reasonable to assume they would plan on 1/4 charge on

        • by tepples (727027)

          If by 'everyone' you mean people who live more then 50 miles away.

          And that's a lot of people until real estate near decent-paying jobs becomes more affordable.

      • by jank1887 (815982)

        that's a good point. Chevy volt is rated at ~35miles electric. that would get me to work, but not back home again. so I'd need to recharge or plan on using the gas assist engine on the way home. recharge is 10hours at 120V or 4 hours at 240V if temperatures are moderate. (forget winters). If I _needed_ a full charge at work, I'd have to do it at 240V, which is at ~twice average power. Maybe I could handle getting only a partial fillup during the day to spread it out with a 110 line, but still, I'd need to

        • by CastrTroy (595695)
          The sad point is that this is all too common. People live way too far from work. I live 7 km (4.3 miles) from work and I love it. I don't really know how people deal with living so far away from work. Travelling hours each day. The furthest I've ever lived from work was 25 KM (15 miles). Didn't like it at all. I suppose if traffic didn't exist it wouldn't have been so bad, but that doesn't happen for most people either. It was only marginally slower to ride my bike. (1 hour 15 minutes by bike vs. 1 h
      • by AJWM (19027)

        A couple of blocks from where I work, there's a parking lot roofed over (carport-style) with solar panels. (Part of a government demo project, the power is fed to the grid.) I could easily see these becoming charging stations as e-cars become more prevalent. Has the nice side effect of keeping the cars shaded and cool, so less need for car A/C in summer, at least for short commutes.

        (Guesstimating the numbers -- 2m by 6m of panel per vehicle, panel efficiency <10%, so maybe 1.5 kW per vehicle? 12

      • How many people have a commute longer than 20 miles (Chevy volt) or 50 miles (Nissan Leaf) one way so charging at work is . If you are like me neither one would be a good option all the time (the Leaf would work most of the time) but I doubt many people consistently drive more than 100 miles a day.
        • I doubt many people consistently drive more than 100 miles a day.

          Then you doubt that many people work in parcel delivery or other forms of on-site service. I doubt clients will let service technicians steal [wikipedia.org] their electricity.

    • we have more then what is needed on the generation side but what is lacking is the power transmission that needs to have alot more wires / links.

    • Easy. You have to build more NUCLEAR POWER stations to power all those green cars.
      • Yes, nuclear. Plus of course more wind and tidal generation. All 3 of which are green sources.

    • by geekoid (135745)

      Yes, the hippie friend is a great source~

      Here is what we will do:
      we will build more power plants.

      Wow, that was hard, wasn't it?

      preferably 4th gen nuclear power plants, and industrial solar power.

      Full charge most packs at 6.6Kw would take 4 hours, or so.

      That's a full charge, something that wouldn't happen most nights on a modern electric car.

      So NO it won't be "WAY more power" then home HVAC units. Less, in most cases. That said, HVAC is a poor comparison because it encompasses so many different technology, a

    • by Skapare (16644)

      Now imagine half the population plugging cars into the gird every night that draw WAY more power than any consumer HVAC unit.

      Huh? My A/C system uses a 40 amp 240 volt dedicated circuit. They are showing these cars as having a 15 amp 120 volt plug. How much do these cars really need during recharge?

      • Huh? My A/C system uses a 40 amp 240 volt dedicated circuit. They are showing these cars as having a 15 amp 120 volt plug. How much do these cars really need during recharge?

        More than that if you want to charge it faster than overnight. Once you get into the fine print the recommended way is a 240V charging station. The Volt, for example, takes 10-12 hours to charge on a 120V 15A outlet. But it will charge in 3-4 hours with 240V. This 240V charging station [spx.com] wants a 40A circuit. Same as your A/C system.

    • We've got infrastructure issues. That's nothing new. We need to upgrade/replace huge chunks of our nation's infrastructure. But that isn't really the fault of electric cars.

      Electric cars are supposed to be an improvement over regular gasoline cars largely by centralizing the power generation. So you can (hopefully) get better efficiencies and less pollution and all that.

      Obviously that electricity needs to be distributed out to wherever the cars are charging. And right now, if everybody suddenly switche

    • I haven't seen any "The electric car is gonna save the world!" hype from any greens. Only time you hear that is from trolls constructing straw men.

      As to "hugh power spikes" - An typical overnight charge of an electric car would be done at 1.5kw*. A kettle is typically 3kw*. So making a cup of your favourite hot beverage is more of a spike than charging an electric car overnight.

      On a fast charge from a beefier outlet, it might be 6kw*. 2 kettles worth.

      (*This may vary from country to country given different

    • The big question that seemed/seems lost in all this "The electric car is gonna save the world!" hype is how an energy grid that can barely handle our energy needs AS IT IS is supposed to function when a significant portion of the population replaces their evil petroleum cars with electricity-draining electrics. When I've asked that question in the past to my usual suspect lineup of hippie friends (who also think that organic food and wind turbines are going to save us all too), the only answer I ever got was a vague "Well, most of that'll be happening at night, when the power demand is down anyway." But we're talking HUGE power usage spikes with those cars. Think of how much our system is already taxed when HVAC units have to cool a 10-degree-higher heat wave. Now imagine half the population plugging cars into the gird every night that draw WAY more power than any consumer HVAC unit.

      The issue is not capacity but peaking - as you say "spikes." Adding a huge load, beyond spinning reserves, taxes the system since you cannot handle the load so you have to load shed. So who do you shed? It's not like daytime where big industrial users can be dropped quickly (and are often paid for the ability to do this); it's a bunch of home users who more than likely are the culprit. Plus, it's only temporary since you probably have the capacity just not "right now!"- if you have a nuke with available ca

    • by Fned (43219)

      " Think of how much our system is already taxed when HVAC units have to cool a 10-degree-higher heat wave."

      If there was ever an obvious case for solar, this is it.

      Why new AC is allowed to be installed without at least some kind of photovoltaic offset continues to be a mystery...

  • Could be worse (Score:5, Insightful)

    by DrData99 (916924) on Thursday August 04, 2011 @11:38AM (#36987240)

    You could be charging your car at 2AM in the afternoon!

  • by Attila Dimedici (1036002) on Thursday August 04, 2011 @11:39AM (#36987242)
    These researchers clearly misunderstood the idea of a "smart" power grid. It is not intended to let you control when you consume your electricity so as to save money. It is intended to let the government/corporations control when you consume electricity.
    • Less the government more the grid operators. That data from the various smart devices will be fed into the network apps and market apps to better use limited resources.
    • You sound more than a little paranoid.

      The purpose is of course to smooth out the demand, such that less power stations have to be built to cope with peaks. And to make most use of greener sources of power.

      If you see that as sinister, then you have a mental problem.

      • by Hatta (162192)

        The problem isn't the smart meters. They're a good idea. The question is, who pays and who realizes the benefits? Are they going to lower prices now that their costs are lower due to the smart meters?

      • by Darinbob (1142669)

        Well, there is a bit of cause for paranoia at times. Power companies are absolutely about making a profit. If it weren't for government regulation there would be no cause at all to conserve electricity because more usage means more profits. Power companies used to actually encourage the use of more power. The hands-off free market approach wasn't working. The trick is how to make that greed motive actually work to cut usage. The California model was to decouple utility profits from sales; a fixed cost

  • I doubt that the few people with the intelligence to do this will even get close to being involved with the "smart grid." Be prepared for a decade of power more unreliable than we have now (almost every company I work with has a backup generator).
    • Presumably new fridges etc will come equipped to interact with the smart grid as a feature. Participation will not require intelligence - it'll just happen as appliances get replaced.

  • The rest of the world already has peak and off peak tariffs. This is really no different.

    Given not everyone will get a smart meeter at once, it should be easy for them to map how usage changes along with price and time of day. The suppliers can know before customers what price changes are about to happen, and should be able to adjust their supply accordingly.

  • by loftwyr (36717) on Thursday August 04, 2011 @11:44AM (#36987334)

    He's right! And if everyone in town flushes their toilet at the same time, all the pipes will burst and we'll all die!

    • Re: (Score:2, Insightful)

      by Anonymous Coward

      This is why my whole town flushes at 2AM when toilet usage is at its lowest.

  • by datapharmer (1099455) on Thursday August 04, 2011 @11:45AM (#36987342) Homepage
    The solutions here are a case of "No shit Sherlock." Put in a random offset in the update cycling - They do the same thing for automatic software updates already. If you schedule for an update every half hour it might actually update anywhere from 15 minutes to 45 minutes (adjust delay as needed for application). The random staggering keeps everyone from grabbing an update (and thus cycling their power hungry appliances on) at the same time.
    • "Smart" devices, particularly automotive chargers can also ramp and/or limit their power draw to allow time for supplies to increase/decrease. Randomization of start times combined with ramped power draw and communication with the grid make it a non-issue.
  • I was at a talk last year about how to solve this issues. The proposed solution was to take the decision to use/not use power out of the hands of the consumer by having smart appliances that could be regulated from an outside source. Basically you would nominate "desires" and the "system" would attempt to optimize power usage to meet those desires over the entire local neighborhood (IE delay running the dryer now to put a quick charge in the car so you can go out to dinner, as dinner is more important to
    • by Idarubicin (579475) <allsquiet@hotm a i l .com> on Thursday August 04, 2011 @01:11PM (#36988498) Journal

      The question I raised was basically "Yep the technology works, but how are you going to change the mindset of people away from ME ME ME to US US US?".

      The same way - and the only way - you usually get large numbers of people to engage in apparently cooperative or altruistic behaviour: bribery. Offer people a small reduction in electricity rates (or a cash rebate, or some other real-money incentive) in exchange for allowing the utility to remotely adjust/control their consumption.

      Many utilities (in the United States and elsewhere) are already doing this with air conditioner thermostats. They offer a rebate or rate break in exchange for giving the utility the ability to remotely shut off your air conditioner for a set period of time (generally no more than one hour per day, and often less) during high demand periods. Some have gone to even 'smarter' systems, which allow the end-user a small number of 'overrides'. (Usually you can go without the A/C for a few minutes, but if you're hosting a party and need the cooling, then you can have it on a handful of occasions each year. This little bit of added flex)

      I see no serious technological, political, or social barrier to implementing a similar system to regulate charging systems for electric vehicles. If anything, there's even more flexibility here--the car (and its owner) don't care whether it does its six hours of charging between 9pm and 3am, or between midnight and 6am, or as a dozen 30-minute blocks spread over the whole night.

  • In order to successfully mitigate congestion in a network requires the sender having detected packet loss to cut transmission rates exponentially and then linearly increase transmission rates until congestion is detected (exponential back off). I suspect that power congestion response in a smart grid would be similar, perhaps by doubling the current price if demand is exceeding production but only linearly decreasing the price as production exceeds demand.

  • Which is why, absent mega-watt-hour storage for electric power, wind and PV solar are not useful sources of grid electricity. Once they get above a few percent of the capacity of the grid, their instability currently(*) requires another source of energy that can react quickly when they go up or down in contribution to the grid.

    (*) Sorry...

    • by geekoid (135745)

      There not good source of base power.

      Solar panels can drastically offset the energy drain from electric cars.

    • by jovius (974690)

      Couldn't that be solved by creating intelligent micro-grids, which contribute the extra energy back to the greater grid? Instead of continuing along mega-powerplant route it might be useful to create many smaller and local power plants.

  • In mulitcast network code it is common to randomize scheduling by a factor of +/- 50% in order to reduced synchronization effects.

    Similarly, power use scheduling could be randomized across some range.

  • by hypergreatthing (254983) on Thursday August 04, 2011 @12:00PM (#36987534)

    Perfect solution. Charge capacitor whenever you want at the lowest cost hours. Use said stored charge to power any devices you want at home including your car.

    Yeah i know doesn't exist now/yet. But i don't see why it couldn't, you're moving capacity from the grid to the end point.

  • Systems can be built to deal with this problem, calling it the end of the idea is simply short sighted.
  • ....what?
  • by AJWM (19027)

    My local power company pays me (or rather, discounts my bill slightly) to let them mount a remote switch on my house A/C unit. This lets them shut it off for short periods during peak demand.

    Installing a similar circuit on e-vehicle charging systems would take care of oddly-timed peaks if everyone in the neighborhood is charging their car at the same time.

    tl;dr - just make the grid smarter.

  • I got my smartmeter here in Texas more than a year ago. So far the best data I can get is delayed by 2 days and at 15 minute intervals.

    There are some mythical devices called HAN that you are supposed to buy somewhere to use for instant monitoring inside your house but I have yet to find anybody selling them.

  • What we need to do is stop being superstitious about nuclear power and build safe nuclear power plants, and actually operate them with the emphasis on safety, rather than the emphasis on cost-cutting (read as: profitability). "Alternative" energy solutions are fine and dandy, but they'll either never catch up with demand, or will catch up too slowly. We may yet have fusion power, but it's still far enough away that we can't make that part of the equation. Nuclear fission may not be the best long-term soluti
  • by BitZtream (692029) on Thursday August 04, 2011 @12:43PM (#36988092)

    Wouldn't allow everyone to receive the power at one time. If the plants were overloaded, two things could happen, A) pricing jumps up automatically, causing some devices to not consume power due to their price rate limiting.

    Second, all the smart equipment in the grid could simply not pass full amperage through to the receiver while the plant is spooling up. The smart meters can provide rolling blackouts as needed to keep the grid under control. These smart devices in the home would be aware of they reduced power availability and simply wait until the grid told them there was sufficient power to activate.

    Smart devices that want to turn on at certain times would not turn on exactly at that time, there would be a random number generator which adds some sort of randomized delay so that you set it to run when the price drops to $0.05/hour, and when that occurs, it waits some random amount of time between 0 and 30 minutes. All smart devices do the same thing, effectively giving the grid time to compensate and allow plants to spool up as needed. The smart devices can also be told the grid is overloaded so please wait.

    We're talking about a SMART GRID ... you simply program the devices to avoid the problem. If you don't, its not a SMART grid, its just a grid with some silly controllers on it.

    Second, once the power company realizes that everyone charges their electric cars at 2am during the price drop ... they simply spool the plants up in advance so they are ready for the load. It'll be rather predictable, kind of like the early morning when everyone gets up and starts using hair dryers and electric ranges, microwaves, electric hot water heaters and all that. They just spool the plants up in advance as the load is rather predictable.

    Someone at MIT is missing the tree because they keep looking at the forest.

    The grid and these devices are communicating with each other, the grid can simply tell the devices to wait a minute, its not ready, and if they try now they are going to get denied. This isn't a difficult problem to solve, I'm fairly certain it would be trivial to implement the software required on the cheapest of microcontrollers. An Arduino for instance would have no problem dealing with this from both the grid side or the home device side.

  • by drolli (522659) on Thursday August 04, 2011 @03:09PM (#36990088) Journal

    off peak power usage is a technology of the 60s-80s, e.g. for heating to use electricity used in industry during the daytime.

    i always imagined a smart grid would mean that not everybody turns on at 2am but that you get even a little bit a better rate but letting the company decide when your car will be charged (e.g. sometimes between 1am and 8am).

  • by WaffleMonster (969671) on Thursday August 04, 2011 @03:24PM (#36990274)

    Just randomly bias each smart meter or print different peak/off peak times on everyones bills.

    Realtime minute by minute rates could actually use feedback from the grid to improve reliability or respond to emergencies where n-1 could otherwise not be achived. You just include grid stability in the cost calculation.

  • by Paul Fernhout (109597) on Thursday August 04, 2011 @03:52PM (#36990638) Homepage

    Basically, as part of her graduate work in Ecology and Evolution at SUNY Stony Brook (about 1990), my wife (Cynthia Kurtz) did computer simulations of digital organisms, and discovered that sometimes being "dumb" is really being smart, because you don't stick with the smart crowd who ends up competing over the same resource. People did not want to believe her results because they went against all the "foraging theory" of the time. She only got an MA out of that, not a PhD. She presented her results at an early ALife conference. Now people rediscover that effect in smart power grids...

  • by angel'o'sphere (80593) on Thursday August 04, 2011 @03:53PM (#36990654) Homepage Journal

    Smart grids don't work like the summary is suggesting!
    a) there is no power plant spooled up ... it is surplus power that is sold cheap
    b) it is not that you just "activate your dishwasher". It is a market operation: I buy power for the actual price, is the buy order processed, the dishwasher activates.
    It is impossible in a smart grid that to many dish waters activate.

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