UrbanEden uses multiple hardware and software tools to achieve its primary control objectives: maintaining interior comfort, providing adequate light for the home’s interior and exterior spaces, ensuring a dependable supply of hot water, minimizing annual power consumption, and maximizing annual power generation.
A Microsoft Surface ™ Tablet PC presents information and control options to UrbanEden’s occupants. Central to personal interaction with the home’s systems, the tablet allows occupants to monitor a wide array of details, such as wall temperatures, capillary tube system operation, dry bulb temperatures within the home, real-time energy consumption on all of the home’s circuits, energy generation from the home’s photovoltaic array, and streaming video feeds from the home’s multiple security cameras. Control functions, such as thermostat setting, water heater mode selection, photovoltaic array rack movement, and lighting, can all be carried out directly via this handy control platform.
Programmable Automation Controllers
The major hardware and software components enabling these functional capabilities include two programmable automation controllers manufactured by Schweitzer Engineering Laboratories (SEL). These controllers operate and monitor the radiant (capillary tube) system located in the walls and the roof of the house. Sensors, including wall-embedded RTDs (Resistance Temperature Detection) and liquid-flow meters, provide feedback for the control algorithms running on the SEL units. Using the sensor feedback, the algorithms provide outputs used to automatically control various elements of the system, including a Variable Frequency Drive (VFD) for varying pump speed, as well as two modulating valves for controlling flow rates of the working fluid. The system thus autonomously regulates temperature changes in the walls of the house.
A third Programmable Controller from Automation Direct controls three AC drives which provide velocity control over three Ironhorse™ AC motors. This Do-more™ PLC controlled system provides independent control over the three motor-and-lock circuits needed to move the photovoltaic panel racks back and forth over the house. A C-more™ touch panel operator interface (also from Automation Direct) provides graphical indication - and control - of the PV rack. The C-more “Remote Access” App allows visualization and control of the system from any iOS device.
Also integral to UrbanEden’s monitoring and management capabilities are the Nexia™ Home Intelligence package and the Powerhouse Dynamics eMonitor™. Both systems were generously donated to the project by Ingersoll-Rand Corporation.
The Nexia™ package enables the home’s occupants to do many actions remotely: turn on or off devices plugged into wall outlets, lock and un-lock doors, adjust the thermostat set point, monitor the opening and closing of exterior doors and windows, and monitor streaming video from wireless cameras. These capabilities are made possible using a network of Nexia peripherals –actuators and sensors – which communicate wirelessly over Z-Wave protocol to a central Nexia Bridge™ located in the home. Control commands and data monitoring are done via a Nexia hosted, web-based portal, accessible on the tablet PC.
Also appearing on this portal are data read-outs indicating the home’s overall energy consumption and generation statistics. This information is collected via individual sensors mounted to a circuit within the home’s main service panel. Data collected from the current sensors is sent back, over the web, to Powerhouse Dynamic servers, where it’s analyzed, tabularized, and graphed into an intelligible format. The tables and graphs are accessible to the homeowner on Nexia’s web portal. In addition, Powerhouse Dynamics’ analytics software can provide tips for energy conservation to the home’s occupants.
Multiple studies have shown that people who receive direct feedback on their power consumption reduce their electricity use by 5% to 15%. For a report from the Electric Power Research Institute, please see the attached pdf.