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The Internet Software Science

Reducing Electricity Bills For Buildings With XML 201 201

Roland Piquepaille writes "Even if new buildings are connected to Internet, they usually don't communicate between themselves. And when it comes to electricity, these buildings are selfish and consume what they want without any coordination. Now, an XML-based system developed at Lawrence Berkeley National Laboratory is using Web services to collectively adjust power usage to variations in price. In 'Internet ups power grid IQ,' Technology Research News reports that the system was successfully tested for two weeks on five commercial buildings. 'Beyond price, systems could be programmed to respond to changes in air quality or to tap into sustainable energy sources.' You'll find more details, pictures and references in this overview. [Additional note: The system described here is completely different to the one mentioned in Slashdot last March in Building the Energy Internet.]"
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Reducing Electricity Bills For Buildings With XML

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  • BACnet (Score:5, Informative)

    by Mattintosh (758112) on Tuesday June 29, 2004 @01:04PM (#9561703)
    I work for a building automation contractor, and I can tell you, this stuff has been around for years. There's even a standard for stuff like this, and it's nothing nearly as lame as a new XML-DTD-that-will-save-the-world.

    The standard is called BACnet (Building Automation and Control Network), and it was (and is) developed by ASHRAE [ashrae.org], the American Society of Heating, Refrigeration, and Air-conditioning Engineers.

    We (at my company) are a dealer for a particular brand [automatedlogic.com] of native BACnet controllers and software. It's all web-based. Everyone in the industry has web-based software now. Ours happens to be multi-site, too. And ours can interface easily with several hundred different manufacturers' products, including UPS and generator managers. We also frequently take direct control of chillers, which are huge power hogs. All of this can be programmed to maintain a steady climate, light areas appropriately, and keep equipment from failing prematurely, all while monitoring and controlling power usage.

    This is hardly news, and certainly not standards-compliant.
  • Re:What's the point (Score:3, Informative)

    by StateOfTheUnion (762194) on Tuesday June 29, 2004 @01:08PM (#9561765) Homepage
    Because that's not how you run all your industrial electrical systems . . . Why not turn off the grocery store freezer for 20 minutes during the peak electrical demand period of the day? It won't hurt the products and over the course of a month it might save signicant money . . . or why not let the ambient temperature in the building go up about 3-5 degrees F during peak electrical demand hours . . . it won't cause any real problems and it might save some money.

    Or even better, run the freezer and air conditioner at full blast before peak hours and "store" the energy as a cooler than normal building or freezer. Then you can shut them off during peak hours and not worry that the temperature will become too hot.

    If you have a real time system that is updated with pricing, it can use more energy during non peak times and/or use less during peak times . . . This has the advantage not just of saving the consumer money but of also helping to balance the load on the power grid.

  • Re:What's the point (Score:4, Informative)

    by drinkypoo (153816) <martin.espinoza@gmail.com> on Tuesday June 29, 2004 @01:09PM (#9561769) Homepage Journal
    You might run the AC at full and pre-cool parts of the building that aren't being used, then you could blow that cool air around the building by feeding medium-temperature air into the system later.

    You might also decide that people just have to live with a warmer office when power costs peak. Nudging the temperature up a couple of degrees might make a big difference at peak rates.

  • Re:What's the point (Score:5, Informative)

    by Mr. Underhill (119443) on Tuesday June 29, 2004 @01:26PM (#9561975)
    Demand limiting is big bucks. It is common to have a contract with a power company that says that during peak times you will not exceed a given kWH in a 15 or 30 min interval. Often the penalty for doing so is severe, such as a upward change in rate structure for the rest of the contract.

    Even less harsh contracts usually involve a peak kW demand charge that is in addition to the normal kWH charge.

    Running the AC at half power all the time is often not realistic. Big ACs have control systems that automatically change their output level according to demand anyway. The functionaly described here is actually nothing at all new to those control systems. Just the XML part is new and even that is over a year old for my company.

    Take a look at Johnson Controls, Siemens, Automatated Logic, and Honeywell. All of us have controls systems that do in fact talk between buildings using TCP/IP if not XML in particular. (Bacnet is the big standard protocol in our world actually.) All of us have control systems that does everything that article talks about and much, much more.
  • Re:Price changes? (Score:1, Informative)

    by Anonymous Coward on Tuesday June 29, 2004 @02:00PM (#9562412)
    My local power company has a variety of usage contracts for industrial users.
    The typical time-of-day contract is negotiated for a low rate that goes up during peak load times (summer days), and the increment is based on the spot price that the electric company pays for outside electricity. One industrial customer may pay a flat 3 cents a kWH year-round. Another time-of-day industrial may be paying 2 cents a kWH for the non-peak usage low rate - a fraction of a penny above the cost to generate -but sugnificantly nore during peak times. (I'm intentionally NOT using exact numbers) Home users may be paying 7 cents a KWH at the same time.
    It gets interesting in the summer. Spot electricity during peak summer hours often go above 5 DOLLARS a kWH and has been above $35/kWH. You're still paying 7 cents at home, but the time-of-day usage industrials are taking a beating.
    An intelligent industrial user that may have a Megawatt usage would shut down for a while rather than pay a 5 million dollar electric bill. To sweeten the pot, the utility will under some contracts refund to the customer some amount that the utility saved due to the reduced consumption, and that has been at times a significant amount of money. The business decides what they want to do, but the numbers are already in front of them as the load costing programs have been around forever. A few shutdown the plant and turn on their waste-product electric generation to sell electricity back to the utility at those market prices at those sweet prices.

    And, brownouts are avoided so people at home don't die from the heat and people's motors aren't damaged by the brown-out.
    That way the utility doesn't have to spend another half billion dollars on new generation that would
    only be used for a few hours a day in the summer.
    It works out better for everyone

    Now the local company is offering a discount to home-owners that allow a remote cut-off to be placed on their air conditioning unit. This gets operated during peak times (I think for a max of 1/2 hour off), and they can rotate through the customer base so no one person gets screwed.
    Because the problem is a threshold phenomenon, the utility can save the customer base millions of dollars by just shaving consumption by a few percent. And, the beauty of it is that it's all based on market pricing and customer choice.

    What's cool about the XML plan, is that it provides the end user with the information needed to make the choices in a format that doesn't tie the user to some proprietary software package/scheme. My local company has provided this info for some time, but I'm sure many companies do not share real-time pricing, particularly smaller ones that don't do variable pricing contracts.

    My local rates are among the lowest in the country and without government subsidies unlike some places.
    BTW, I have never been a electric company employee.

  • Re:Followup Q (Score:3, Informative)

    by Mattintosh (758112) on Tuesday June 29, 2004 @02:18PM (#9562595)
    do these systems control the lights

    Yes. Speaking strictly about ALC [automatedlogic.com] products, you can either turn the lights on and off with control programs in the general purpose "HVAC" controllers (which have various configurations of inputs, along with a fully programmable microprocessor from the PPC family), or you can buy a Triatek (made by ALC) lighting system, which undoubtedly has more features for lighting, but isn't quite as general purpose.

    Basically, the system is a set of networked control modules, each able to turn things on or off (Form C contact, 3A max), ramp up and down with a variable output signal (0-10VDC or 0-20mA), and sense inputs of several types (thermistor, dry contact, 0-10VDC, 0-5VDC, 0-20mA). The controller itself can handle timed schedules and network-viewable points (inputs or outputs on other modules, broadcast over the network). A central server hosts the software and user interface, but each module has its program flashed into EEPROM. Reprogramming is a matter of a few seconds, but loss of power doesn't necessarily cause catastrophic failure.

    To sum up: you can control damned near anything with a system like this.
  • Re:XML Hype (Score:2, Informative)

    by NineNine (235196) on Tuesday June 29, 2004 @02:43PM (#9562919)
    Embarassment is one thing, but ever see a file with a tilde separator? Imagine trying to explain to every DBA wtf a "tilde" is...

    "Yeah, I used tilde as a separator because there isn't a single one in all of the data, and there probably will never be."


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