LowEnergyBuildingServices - Highly efficient presence detectors and end user technologies
End user technologies are used in plus-energy office buildings and office buildings in great numbers to control lightning, ventilation systems etc. Highly energy efficient presence detectors, control systems for sun shades etc. are defacto not available on the market. The Standby power consumption for currently available products, for example motion detectors, lies around 1 to 3 W. For plus-energy office buildings the minimization of the power consumption of these components are a central criterion to produce more energy on the site of the building than to consume.
Contents and Objectives
The superior goal of this project was to show that end user technologies such as presence detectors have great energy saving potentials (up to 90 %) and to document this by sketching a highly efficient presence detector which should have a standby consumption under 0,05 W after optimization. Further goals were to document the state of the art for motion detectors now available and a study how to transfer the gained knowledge to other end user technologies.
For documenting the state of the art a market and energy consumption analysis was made. The energy consumption of motion detectors and three typical control components were measured. In a saving potential analysis the most important factors for the energy consumption of these components were determined. A highly energy efficient presence detector prototype was built on basis of these results by optimizing the construction of the sensor, the power supply and the output circuit. The prototype was measured constantly and optimized to reach a standby consumption of under 0,05 W. The transfer of the gained knowledge from the development of the highly energy efficient presence detector was examined and implemented in three typical control components.
A highly energy efficient presence detector was successfully sketched in this project, which undercuts the intended standby consumption of 0,05 W. The results of the energy measurement show a standby consumption of 0,0076 W (24 V version) and a standby consumption of 0,038 W (230 V version). The standby consumption in comparison to conventional motion detectors was reduced by 95 %. In addition three components were modified and optimized.
Prospects / Suggestions for future research
The actual technology of presence detectors is exhausted concerning the minimization of standby consumption. The next generation of presence detectors have the ability to detect motionless persons. Motion detectors available now compensate the detection of motionless persons by long follow-up times, which leads to a high energy consumption for the controlled building service components (for example lighting). The core component of these next generation detectors is the Panasonic Grid-Eye with 64 temperature points. The detection of motionless persons will be possible by the continuous analysis of the 64 temperature points. The change of presence can be detected within one second.
Bmst. DI Helmut Schöberl, Schöberl & Pöll GmbH
DI Richard Hofer, Schöberl & Pöll GmbH