When the fridge speaks to the computer ...

Intelligent systems will help save energy in the home in the future

With his mobile phone as a display and control device, the resident can control the energy consumption of his devices. © Fraunhofer FIT
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A cell phone that detects and reports on power guzzlers, a refrigerator that pre-cools before electricity gets more expensive - new technologies and software solutions will make it possible to control household power consumption much more accurately and thus save costs. These systems are based on networked systems and mobile applications, both focal points of this year's CeBIT.

The supply of electricity and also the consumption are not continuous: At night, when everything sleeps, there is an abundance, in the morning and in the evening, the energy providers hardly come after. An anti-cyclical power consumption could mitigate this mountain-and-valley journey and thus save costs. One way to achieve this approximation is price incentives: if the supply is high, the price falls and vice versa. What is needed are devices that can intelligently adapt to the prevailing price situation. Washing machines that start alone at night or refrigerators that pre-cool before the evening primetime.

Software reacts to price development

Professor Frank Bomarius, deputy director of the Fraunhofer Institute for Experimental Software Engineering IESE in Kaiserslautern, and his team are currently developing a software that sits behind the electricity meter and ensures that energy consumption is adjusted accordingly. "Information about the expected price development in the next few minutes and hours come from the outside, ie from the utility company, short RU, " says the computer scientist. These must be combined with the needs and preferences of the consumer. "Our system ensures that household appliances are optimally controlled according to these specifications."

Refrigerator as energy storage

It is not simply about switching off the air conditioning or washing machine at short notice, when the price of electricity rises. It is much more intelligent, for example, to use refrigerators or freezers as energy storage devices. "If the energy provider reports that electricity is becoming scarce and expensive in two hours, these devices can already pre-cool their contents and ensure that they do not need any power for a long period of time, " explains Bomarius. The same applies to the hot water or heating.

Computer determines maximum value

The system can be controlled by a PC, where the consumer enters his wishes: he determines the temperature for cooling or heating, calls a maximum price that he wants to pay for the kilowatt hour, or limits the maximum consumption. Then the software calculates when which devices are switched on and off in the household. The direct access of the computer to washing machine or heating is via electrical lines or via radio. In practice, the intelligent energy management will run on the same computer that controls other functions of the house: lighting and heating, shutters, lockers or assisting household helpers. display

First practical tests later this year

In 2010, the system in Kaiserslautern will be practically tested in some apartments. Of course, it is also suitable for large residential complexes, public buildings or business buildings. There is often already a central building services available, based on the energy management. The researchers in the Kaiserslautern project are negotiating with the local energy provider what the communication with the utility companies will look like. "We want to keep the interface very small, " says Bomarius. "It is unclear why my utility should know and influence when to cool, heat, watch TV or cook."

Mobile loses power guzzlers

The researchers also have another source of support for saving energy and costs: Researchers at the Fraunhofer Institute for Applied Information Technology FIT in Sankt Augustin have developed an application that monitors the energy consumption of individual household appliances shows. This helps to identify the energy guzzlers in your own home and gives consumers a feeling of which devices consume energy and where much can be saved. The basis for this is the wareHydra middleware developed by the institute, which has been extended by a special energy protocol.

With his mobile phone as a display and control device, the resident can control the energy consumption of his devices, explains Markus Eisenhauer, who develops the system. Thus, he can, for example, display the consumption per room, switch devices on and off or dim lamps. And there is another special feature: the camera image of the mobile phone can be called a "magic lens" be used. To do this, the camera is aimed at the corresponding device and receives the appropriate current power consumption as if by magic.

(Fraunhofer Gesellschaft, 03.03.2010 - DLO)