Feasibility study of energy harvesting based wireless sensor network for building environment monitoring and management.

다국어 초록 (Multilingual Abstract)

Nowadays, the design of energy-efficient green buildings has been gaining increased attention in building construction and management. Among various emerging technologies, wireless senor network (WSN) provides more convenience and flexibility in the implementation of intelligent building operation control and management. In a case study where WSN was implemented in buildings at the University of California, San Diego, in 2012 (San Diego case study, 2012), it has been demonstrated that the deployment of WSN-based building management systems results in about 27% savings in energy usage and hence plays a crucial role in energy-efficient green buildings. Unfortunately, these existing WSN systems present a significant maintenance challenge. From a building operation and maintenance perspective, WSN systems are often expected to run for at least several years (and even indefinitely) without needing maintenance. However, these existing WSN systems are powered by batteries. As batteries have limited energy capacity due to their stringent size constraint (only a few cm2) in the sensor node, batteries are usually drained off in several months and hence require frequent replacement. Due to the prohibitive labor expense and user inconvenience resulting from frequent battery replacement, conventional battery-powered WSN systems pose a sizeable limitation on wide deployment in practice.
The purpose of this study was to investigate the feasibility of a new WSN technology that can be powered through harvesting indoor ambient light as an energy source. As long as ambient light radiates, the proposed WSN system will never run out of energy. Therefore, it has great potential to overcome the maintenance challenge in the conventional WSN systems. First, this new technology was implemented in KNOY Hall at Purdue University. Experiments were carried out to validate the functionality and reliability of this technology. Second, cost estimation and payback analysis were conducted to illustrate energy savings and economic benefits of this new technology. Third, interviews were utilized to collect comments, concerns, and opinions from the Purdue Physical Facilities Department about the practical deployment of this new technology at the Purdue campus.
The interview participants in this study perceived the use of this new WSN technology to be as good as or better than conventional wired/wireless sensor network technology. These interview participants considered the new technology very attractive as an alternative technology candidate in future building renovation projects at the Purdue campus. In addition, several critical design factors and parameters were identified through interview data analysis, along with suggestions for future research and implementations.