Association Report: NEMA: What Language Does your Appliance Speak?
August 30, 2008
The era of simple home appliances has come to an end. New appliances with intelligence are taking their place. The next step is appliances that talk. They will not necessarily speak English, but they will communicate with one another. And that conversation may eventually include the electric utility. This trend is all part of the evolving Smart Grid.
Smart Grid is the term used to describe the nation’s electrical grid enhanced with monitoring, analysis, control, and communication capabilities. Smart Grid includes the entire electrical grid, all the way from the power plant to the appliances inside the home.
The National Electrical Manufacturers Association (NEMA), representing over 400 electrical manufacturers, is at the forefront of the Smart Grid evolution. The Energy Independence & Security Act of 2007 (EISA) calls for NEMA to work with the National Institute of Standards and Technology (NIST) and other stakeholders to coordinate the development of interoperability standards. These standards will define how the various components of the Smart Grid communicate with one another.
At this point, there are several layers of communications anticipated for the Smart Grid. Transmission equipment and utility system operators may speak one language. Electrical equipment inside utility substations may speak another language. Utilities may use another language to provide two-way communication to residential and commercial electric meters. And finally, appliances inside the home may speak another language.
Several utilities around the country are already installing smart meters. These meters are part of a system called Advanced Metering Infrastructure (AMI). This system offers a variety of capabilities including demand response, outage reporting, remote turn-on/turn-off, real-time pricing, two-way utility/consumer communication, and Internet-based energy and bill monitoring. A major feature of the AMI system is to provide real-time price signals to the home or business. These signals can be as simple as turning on a red light indicating that electricity is more expensive than a typical day. Or, the signals can be as complex as a database of hourly electricity rates for the next 24-hour period. In either case, the homeowner or business will have the opportunity to modify its use of electricity in response to the price signals. This is where the appliance designers and manufacturers come in.
Smart Grid will allow homeowners and businesses to utilize electricity as economically as possible. For example, one may want to keep the thermostat set at 75 DegF in the summer when prices are low, but be willing to increase the thermostat to 78 DegF if prices are high. Similarly, one may want to delay drying laundered clothes until 9:00 p.m. if it can be done for 5 cents per kilowatt-hour (kWh) as opposed to 15 cents/kWh in the afternoon. People will have the choice and flexibility to manage their electrical use while minimizing their costs.
However, this means that the appliances will need some way to communicate with one another and will ultimately need a way to respond to price signals from the utility. In some cases, the home or business will have an energy management system that receives the utility’s price signal and commands the appliances what to do. In other cases, the homeowner may want the utility to automatically turn off the water heater or increase the setting on the air conditioner by 2 degrees when the cost of electricity exceeds 20 cents/kWh. In either case, there will need to be a communication standard so that all of this works seamlessly. As of today, there are several standards being discussed to govern these communications, including ANSI C12.22, ASHRAE BACnet, ZigBee, and others. No one knows how these standards will play out. However, appliances designers should monitor the situation to keep abreast of which approaches are gaining the most attention. To learn more, visit the websites of DOE, NIST, NEMA, ASHRAE, IEEE, and others.
In the end, all of these different systems will hopefully work together to create a smart electric grid that is more efficient, more reliable, more secure, more economical, and safer than today’s electric grid. In addition, the new Smart Grid will take advantage of renewable resources and distributed generation, will reduce greenhouse gas emissions, and will provide more opportunities for consumers to control their use of electricity and ultimately control their electric bills.