Smart PowerMay 25, 2007 By: Melanie Martella, Sensors
As a general rule, humans aren't terribly good at planning ahead or dealing with distant threats. We do immediate threats well, however: give us a nice, meaty challenge with a looming deadline and people can become really, really inventive. The majority of people didn't have global warming on their threat radar until rising energy prices and extreme weather started hitting us in the pocketbooks. Now several movements are afoot to boost energy efficiency.
Since power generation is a major producer of carbon dioxide and since we are surrounded by electrical and electronic devices on a daily basis (ever wandered around during a power outage and tried to find something to do that didn't involve flowing electrons?), one way to lessen carbon dioxide production is to just use less energy, obviating (or at least lessening) the need to construct yet more power plants.
An article titled "Coalition to Make Building Energy-Efficient" ran in the May 17, 2007 New York Times. I'll quote the introductory part of the article:
A coalition of 16 of the world's biggest cities, five banks, one former president and companies and groups that modernize aging buildings on Wednesday pledged investments of billions of dollars to cut urban energy use and releases of heat-trapping gases linked to global warming.
Under a plan developed through the William J. Clinton Foundation, participating banks would provide up to $1 billion each in loans that cities or private landlords would use to upgrade energy-hungry heating, cooling, and lighting systems in older buildings.
The loans and interest would be paid back with savings accrued through reduced energy costs, organizers of the initiative said at a news conference in Manhattan. Typically, such upgrades can cut energy use and costs by 20 percent to 50 percent, they said.
People in charge of industrial facilities, commercial buildings, and homeowners are increasingly choosing more intelligent and sophisticated systems for HVAC, lighting, and other building automation applications to improve comfort while also keeping a watchful eye on energy usage. And the utility companies aren't dragging their feet, either. They've been busily investigating demand response networks.
Electricity is a real-time game. If a utility finds that it isn't generating enough energy to supply the demand it has two options: it can add generation (get power from elsewhere to make up the shortfall) or it can shed load (cut off parts of the grid). For years, utilities relied on one-way load control; the utility could signal load controllers installed on energy-hungry appliances, such as air conditioners, and the appliance would power down. Unfortunately, this approach didn't give a quick enough response, annoyed customers, and didn't provide feedback to the utility that their attempt to control demand was working.
Enter the world of demand response—two way communications between the utility and the consumer. Rather than turning off the air conditioner to lessen demand, the utility could bump the thermostat down by a couple of degrees; if the demand/response system is implemented for all the customers of the utility, such a minor change (to the consumer) has a large effect for the utility (lessened load).
Here's an article from Transmission and Distribution World, discussing Florida's adoption of load management and demand-side management to give you some more background.
ZigBee Branches Out
ZigBee, the low-power wireless networking protocol that's been increasingly adopted for building automation uses is moving into the energy utility space. Many of the ten top metering companies have, in fact, joined the ZigBee Alliance and several utilities have joined as well. Why? Because ZigBee lends itself very well to intelligent electricity metering and in-building load control. Because it's wireless, it's easy to install. Because it's mesh-based, it's robust. Because it's standards-based, it offers interoperability between devices from different manufacturers. It's designed to use battery power and to be very frugal with its power use. More importantly, the technology is ready for use today—a recent demo had a Cellnet intelligent meter talking to a local utility's own network and the ZigBee Alliance is setting up other demo facilities to showcase its in-building load control capabilities. It's Advanced Metering Infrastructure (AMI) Profile links existing in-building or home area networks (HANs) to smart energy grids.
If our global hunger for electricity continues at the same pace, we'll need 1900 new power plants by 2030. It's time to get more bang for our buck and smart metering and smart energy grids are showing the way.
Most Read Articles