For most people, the amount of energy that each electrical appliance in a household uses is a mystery. From the television to the coffee maker to the computer to the refrigerator, each device consumes electricity and represents an opportunity to reduce household power consumption.

The Yello Strom Sparzähler ("savings meter") is designed to change the way consumers use electricity. Made of a communications module integrated with an electrical meter, the Sparzähler not only measures electrical usage, it also provides consumers with actionable intelligence on the real-time power consumption of household devices.

With the development of Sparzähler, Yello Strom redefines the level of service that utility providers can provide their customers. In addition to reliable sources of energy and accurate, on-time account statements, Yello Strom will soon deliver its customers a new service that provides consumers with the information they need to help reduce power consumption, lower energy costs, and minimize their impact on the environment.

A Way to See Energy Use

From the hot water heater to the washing machine to the television, most consumers now have dozens of devices using electricity. One challenge with household energy conservation is that it is hard for consumers to understand the impact of each device. If consumers could easily visualize the amount of energy used by each device, then they would be more likely to change their behavior to reduce the amount of energy consumed in the household.

The problem is that energy usage is largely invisible, and few consumers use appliances with any thought to the amount of energy being consumed. Each flip of the switch, however, results in some amount of energy use that is reported to the power provider and then billed at the end of each month. In most cases, this is the only engagement the user has with their power provider.

The product of collaboration between German-based energy provider Yello Strom and Microsoft Deutschland GmbH (a subsidiary of Microsoft Corporation), the Sparzähler enables the user to understand exactly how much energy is used or saved each time they turn on or off a device.

Real-time Data Increases Awareness

"With Sparzähler, household power consumption is no longer obscure and mysterious. For the first time, consumers can view real-time data on the power used during a particular time frame directly on their personal computer," says Andreas Berthold-van der Molen, senior account manager for Microsoft Deutschland GmbH.

"For example, a consumer might want to understand how big an impact turning off a coffee machine would have versus setting it to standby," says Berthold-van der Molen. "With Sparzähler, they will instantly see the reduction in electrical usage, expressed in kilowatts, as well as the subsequent savings in energy cost, expressed in dollars or euros, the moment they switch off the machine."

Sparzähler enables Yello Strom to improve account statement interaction for customers. Rather than waiting for the bill to arrive, customers can track energy consumption throughout the billing cycle, which encourages regular engagement with energy usage and leads to better consumer awareness.

Household Energy Managers

"The Sparzähler transforms energy consumers into household energy managers. With a clear understanding of where their energy consumption goes, customers can make immediate adjustments in their energy usage," says Berthold-van der Molen. "Small adjustments in how appliances are used could result in up to 10 percent savings in energy use without any reduction in personal comfort."

This is especially true of "always on appliances" (sometimes called "vampire appliances"), devices such as televisions, VCRs, and amplifiers that sometimes consume surprising amounts of electricity even when they're not considered to be operating.

In the United States, the average home has about 20 "always on appliances"¹—a number similar to European homes. These quiet energy consumers cumulatively cost their owners millions of dollars or euros per year in energy costs. The problem is that it is hard for people to understand how devices they are not using can still have such a significant impact on their energy consumption. With the Sparzähler, consumers can see the "always on" effect for themselves.

An End-to-End Solution for Energy Providers and Customers

The Sparzähler represents an end-to-end solution that provides great value to both consumers and utility providers.

The core of the Sparzähler is the meter, which is the integration of a communications module and a traditional electrical meter. The communications module makes the meter "smart," enabling the meter to communicate directly with the consumer and the utility provider.

• The meter is integrated directly into customer home computer networks via power line adapters. This enables consumers, through their personal computer, to communicate directly with the meter and gain access to real-time readings of electrical consumption.
• The meter communicates directly with the utility provider over a TCP/IP network. Every 15 minutes, the Yello meter sends consumption information to Yello Strom servers. This information is available to the consumers via a personalized portal on the Yello Strom Web site, where they can view energy usage trends and data that is updated every 15 minutes. Through software downloaded to personal computers, consumers can now track electrical consumption during an appliance's usage cycle, such as that of a hot water heater while someone is taking a shower, or over a specific period of time, such as in the evening, when meals are prepared and the television is in use.

Enabled by Microsoft Technology

Microsoft software is used throughout Yello Strom's smart meter solution. Yello Strom selected Microsoft products because they:

• Are cost-effective, flexible and adaptable.
• Offer easy management and excellent security.
• Provide end-to-end-integration.
• Have full life-cycle supportability.

Yello Strom also successfully took advantage of Microsoft's in-house consulting services to assist with the development of the Sparzähler. Yello Strom is a fairly small company with about 140 employees, so Microsoft software and services enabled rapid product development. With Microsoft's help, Yello Strom delivered prototypes to selected customers after only nine months of development.

The communication module is built around Microsoft Windows CE, which allowed the creation of a secure and reliable interface that was easily integrated with the Sparzähler's software architecture. Windows CE also ensured affordability—both for Yello Strom and the consumer. Windows CE reduced the cost of the meter's development.

Within Yello Strom's data center, Microsoft Windows Server 2003, Microsoft IIS 6.0, and Microsoft SQL Server 2005 ensure the accurate, reliable, and secure storage of information sent by the Windows CE-based smart meter communications module.

The use of Microsoft technology:

• Increased the speed of software development.
• Enabled Yello Strom to take advantage of information assets.
• Is designed to meet current and future needs.
• Is supported through a fixed life cycle by Microsoft.

Given Yello Strom's goal of putting 1.5 million Yello Strom Sparzählers on the market, Microsoft's flexible technology and support is a key attribute that differentiates Microsoft software from its competition.

In the development of the consumer-oriented application, Microsoft Silverlight provided exceptional value to Yello Strom. With Silverlight, Yello Strom was able to rapidly develop a multi-browser, multi-platform, graphically rich and pleasing user interface for graphic energy visualization by using the data collected from the Sparzähler.

The Future

The Sparzähler was unveiled in March 2008 at CeBIT, the annual technology trade show in Hanover. Its release to the public is not yet scheduled.

Yello Strom CEO Martin Vesper says, "We have developed a cost-efficient solution for consumers with the Yello Strom Sparzähler, enabling them to efficiently and intelligently use energy. Our Sparzähler makes the consumption of energy transparent and simplifies the saving of energy. That is the best form of environmental protection available on the energy market today."

Microsoft technology enables Yello Strom to constantly improve the Sparzähler. Yello Strom and Microsoft currently are investigating the integration of the Microsoft BizTalk server into the Yello Strom server system.

With BizTalk, Yello Strom might be able to integrate many heterogeneous backend systems in an efficient and consistent way. BizTalk is also used to regulate the incoming traffic from Sparzählers that have been distributed to consumers.

The Sparzähler offers an excellent example of how technology can help make consumers active decision-makers. People today want to use less energy, help the environment, and be more responsible consumers. But they often lack meaningful information they can act upon.

With the Sparzähler, Yello Strom customers will have information they can use. It's a model that could be emulated by utilities worldwide to help consumers save money and reduce energy use. And that's something everyone can appreciate.