California Smart Grid Center Completes Successful Demonstration Test of Wireless Pneumatic Thermostat Retrofit Solution From Cypress Envirosystems

The test confirmed the WPT’s significant reduction in cost, time and disruption to retrofit legacy buildings and thereby enable them for Smart Grid Auto-Demand Response connectivity. The patent-pending hybrid pneumatic and digital technology employed by the WPT opens up the potential for millions of legacy buildings to participate in peak load reduction and energy efficiency strategies that were previously impractical due to long investment payback and disruption to building occupants.

Approximately 6,000 sq-ft of office space at Sacramento State University was selected for the demonstration test. Prior to the retrofit, the offices used non-communicating pneumatic thermostats for control of heating and cooling. These legacy thermostats were not capable of remote temperature setpoint control and could not interface with the Smart Grid for Auto-Demand Response. Retrofitting them to modern communicating digital thermostats using conventional technology would have been extremely costly, with a payback period of five years or longer. It would also require opening up walls and ceilings, with significant disruption to building occupants.

For the demonstration test, the CSGC used the innovative Wireless Pneumatic Thermostat system, which costs approximately 80% less than conventional technology. The installation at Sacramento State University was completed in about two hours during working hours, with virtually no disruption to occupants. If conventional technology were used, it would have taken several days and required clean-up of asbestos and other hazardous materials exposed during the work.

Once installed, the thermostats enabled remote control and monitoring of zone setpoint, temperature, and branch pressure (heating or cooling demand) via an operator station. The system can also interface with existing automation systems using BACnet, and has a built-in interface compliant with the OpenADR protocol developed by the U.S. Department of Energy’s Lawrence Berkeley Laboratory, which allows communication with utilities for Auto-Demand Response. This interface allows buildings to automatically curtail electricity use during periods of high demand (by increasing the setpoint temperature for thermostats, for example).

“For the Smart Grid to reach its full potential, we will need smart buildings to talk to it. Developing low cost and non-disruptive ways to make existing buildings ‘smart’ is a very important problem to address,” said Emir Jose Macari, Dean of the College of Engineering and founding Director of the California Smart Grid Center at Sacramento State. “The Cypress Envirosystems’ WPT system was installed in record time and has performed flawlessly for the three months of the demonstration test. I am impressed with the system’s performance but above all because of the non-invasive nature of the devices and the installation.”

Similar large-scale retrofits using the WPT, involving over one-million sq-ft, have confirmed each WPT can shed up to 1kW of peak load, and reduce 15-30% of HVAC energy use. The low installed cost enables very attractive payback periods of 18 months or less. To further reduce the upfront cost, the WPT also qualifies for utility incentives in many states, including PG&E, Southern California Edison, and San Diego Gas and Electric in California.

“Most commercial buildings built before 1995 uses pneumatic control systems. This equates to about 70% of the existing commercial building space, or over 60 billion sq-ft, which cannot be easily connected to the Smart Grid. We designed the WPT specifically to address this problem and also to deliver energy savings.” said Harry Sim, CEO of Cypress Envirosystems. “The validation and endorsement from the California Smart Grid Center is a major milestone for the WPT, and will significantly enhance our ability to bid and win Smart Grid projects, especially involving stimulus funding participants. We sincerely thank the CSGC for the valuable service they provide to the community.”