Low-Cost Wireless Monitoring and Control Infrastructure for Small Commercial Buildings
PNNL researchers are working with a team led by NorthWrite Inc. to create an innovative wireless technology platform for performance monitoring, diagnostics, and control of equipment and systems in small commercial buildings. The platform will provide cost-effective energy management and maintenance services by making them available via an Internet browser on the server of an application service provider (ASP). The proposed infrastructure will integrate wireless mesh networking technology with wireless telemetry, automated fault detection, diagnostics, control, and the ASP delivery model. The system will be tested by applying it to rooftop HVAC units and lighting systems. The development team also includes Sensor IQ, Trane, and Texas A&M Energy Systems Laboratory.
An overall schematic of the system structure concept is shown below.
Data are collected from sensors distributed throughout the building and transmitted by wireless nodes to a central “wireless master control module (WMCM)” using short-range wireless mesh networking technology. The sensors monitor various energy-using systems in the building: HVAC units, lighting, and other equipment. Data are received at the WMCM, where they are processed by diagnostic and control algorithms. Supervisory control actions are communicated from the WMCM using the same wireless network to nodes connected to control actuators, which implement the supervisory control actions.
Diagnostic conclusions and important monitored information are communicated from the WMCM using long-distance wireless telemetry to a network operations center (NOC), where data are archived, further processed, and made available to users through web interfaces. Building owners, operations staff, and service providers then securely view the status of equipment and systems in their buildings simply using a web browser on a computer with an Internet connection. No software need be installed on each user’s software. With the right security permissions, authorized users can access the information for their buildings from anywhere.
This infrastructure, targeted at small and medium-size commercial buildings, enables continuous monitoring of the status of building systems. There is no longer a need to wait for semi-annual inspection and servicing. The system alerts operators and service providers when problems occur. Damage can be pre-empted by condition-based servicing. Systems run more efficiently, using less energy, having lower peak electric demands, saving bill payers money, and prolonging the useful life of capital investments.
Time spent by service providers is minimized by informing them of the condition of all equipment prior to arriving on site. Before arriving, the service provider knows the type of servicing needed by each piece of equipment. Service actions can be targeted, spending more time on units that require the attention. Technicians can plan ahead, arriving on site with the parts and equipment to meet the unique needs of each situation.
Building owners and operators save time and money. Service providers can offer a level of service a step above the competition at the same cost. Together they provide a level of performance and efficiency not possible currently for small-to-medium commercial buildings.
This infrastructure and a system of prototype applications is under development and will begin field testing in early 2006.