Perfect balance

Greener load control with smart appliances

By Gabriela Ehrlich

At CES (Consumer Electronics Show) 6-9 January 2011 in Las Vegas, US (United States), smart appliances took centre stage. Many manufacturers displayed appliances that not only add a lot of convenience but also can be turned on and off safely and remotely. This feature may seem trivial, but until the Smart Grid is a reality everywhere, “cycling” appliances during peak hours may represent a green solution for load control. During the Smart Grid Homes conference that was held at CES, experts from manufacturers and utilities discussed the potential of appliances for load control.

Visitors at CES 2011

At CES, manufacturers from GE to Kenwood to LG Electronics and Samsung displayed smart appliances that chat, text, tweet, communicate with smartphones, stream music from the Internet, and more. In case of fault, they alert the service centre and know which part needs replacement.

Today’s smart refrigerator or oven comes with the capability to download recipes; it lets its owner keep up with the news, create task and shopping lists, upload photos and download apps. The smart fridge knows when the milk is over date and how many eggs are left.

Extra value while waiting for the smarter grid

The smart appliance market is expected to grow by 50 % over the next four years and reach a market value in the tens of billions of dollars. But manufacturers all agree that to woo consumers smart appliances need to offer a whole lot more than energy efficiency and the ability to communicate with other appliances in the home. Smart appliances need to become a mainstream product, priced accordingly. Consumers want appliances that give them a lot of extra value, even if the Smart Grid is not yet at their door step. The appliances must be very, very easy to manage; consumers shouldn’t have to configure or set up anything. A smart appliance needs to work straight out of the box.

Right now: appliances can help manage the grid

Meanwhile, appliances, and even more so smart appliances, may already represent a great tool to better manage the grid, even without a single smart meter signal around.

Rob Pratt of Pacific Northwest National Lab in Richland, Washington, US, explained that appliances can help significantly reduce the cost for managing “intermittent renewables”, such as wind energy. Rather than bringing on a power plant to balance the grid, it is possible to shut down appliances for 10 minutes or so, doubling the operating reserve to cope with peak demand. Edison Power is already taking advantage of this: it has more than 350 000 customers, with 450 000 appliances signed up, and cycles appliances for 10-minute intervals when needed. This gives it 750 MW to “play with”, roughly the generation of one nuclear power station.

Stop and start, safely

But some appliances can’t be shut off indiscriminately. Manufacturers are now adding functionalities to their appliances that allow them to be safely stopped and started. Charlie Smith from GE (General Electric), who is also active in IEC TC (Technical Committee) 59 MT (Maintenance Team) 9: Household electrical appliances – Measurement of standby power, which has just issued its new International Standard IEC 62301, Household electrical appliances - Measurement of standby power, explained: “Almost 85 % of the energy used in a household can contribute to balancing the grid. Many devices can be cycled to optimize energy consumption. GE appliances have a built-in ability to delay start, which allows dropping the load for 10 minutes or so.”

He gave the example of a dryer that draws almost 5 000W to dry a pair of jeans in 30 minutes. However, when the owner doesn’t need the jeans immediately, he can select a reduced energy mode where the consumption can be trimmed down significantly. In addition, when needed, the dryer can go into fluffing mode, where it simply continues to turn to keep the laundry from wrinkling but where energy consumption is nearly halted.

But reaching in and doing direct load control is complex for utilities. With the Smart Grid, utilities will be able to provide event or prize alerts and customers can determine, via their home area network, how they want to react to the alert. This will avoid that utilities need to reach into the home, micro-managing devices and energy consumption for them.

Not waiting for tomorrow

In the meantime, life must go on. Rather than waiting for the future, all participants agreed that partial solutions can be achieved already today. The question then remains: How can all these different appliances and other devices communicate with each other now?

While manufacturers don’t expect to have one standard that fits all any time soon, there are solutions available to overcome this problem. The idea is to create a hub approach, using a simple, low-cost device that connects to the home energy management system. This hub allows different devices and appliances to communicate in their language via Wi-Fi, Zigbee or over the electric wire. This is a first step towards a connected home.

And while the connected home is important, LG Electronics projects a future that will be based on the home-to-grid scenario where all devices will be able to communicate with each other, taking into account all distributed energy resources around the home (solar, wind, storage) and all devices that consume energy. LG is working on a solution that will allow running individual devices and appliances so as to optimize household energy use throughout the day.

CES 2011 Visitors at CES 2011