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Reducing Electricity Bills For Buildings With XML
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.]"
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, the American Society of Heating, Refrigeration, and Air-conditioning Engineers.
We (at my company) are a dealer for a particular brand 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.
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.
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.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
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.
do these systems control the lights
Yes. Speaking strictly about ALC 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.
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."
"...."
"It's the button right under the ESC button plus shift"