Session: 02-01: Building Energy Efficiency Technologies

Paper Number: 142718

142718 - Introducing the Heat Index Thermostat: A Programable, Energy Efficient and Thermal Comfort Driven Thermostat 

Abstract: 

A smart thermostat is a device that allows you to control the temperature of your home or office remotely. It can be programmed to adjust the temperature automatically based on your schedule, or you can manually adjust the temperature from anywhere with an internet connection. Smart thermostats can also learn your preferences over time and adjust the temperature, accordingly, minimizing energy AC energy consumption in the process and reducing the associated energy bills.

In this talk, I will introduce our innovative Heat Index Thermostat. A patented programmable, energy efficient and thermal comfort driven thermostat which regulates the home's thermal comfort based on the space temperature and the indoor relative humidity. The novelty lies in the regulation model using relative humidity measurements to enable multiple modes of operation. The thermostat manages the Air Conditioning (AC) setpoint temperature so that the space effective (human-perceived or feels-like) temperature matches the occupant's original set point temperature. When the end-user chooses a temperature setpoint, the thermostat employs embedded logic to determine the temperature that achieves an effective temperature matching the original end-user setpoint. Interestingly, the Heat Index Thermostat operation results in energy savings when the indoor relative humidity is below 60%. The amount of energy savings increases with decreasing indoor relative humidity. The thermostat consists of dry-bulb temperature sensor, a relative humidity sensor, a microcontroller, a memory card, input power terminal, output voltage terminal and the required electronics components. The thermostat logic receives the instantaneous temperature and RH data from the device sensors and calculates the effective temperature. The device compares the effective temperature to the end-user setpoint temperature and determines whether the two values are within range or outside the acceptable range. If the temperature differential is outside the acceptable range the thermostat controller will use the available calculators (or a tabulated values) to determine the equivalent set point temperature that will provide an effective temperature equal to that of the end-user setpoint temperature. The thermostat controller then sends a command to the AC to adjust the setpoint temperature to the new value. The numerical and experimental results indicated energy savings of about 6% and up to 9% when RH is at or below 40%. For a 5 Ton central AC unit with an annual 2000-4000 hours of operation, this translates to an annual savings of approximately 2100-6400 kWh.

 

Reference

Beitelmal, A.H., “Heat Index Thermostat,” United States Patent no 10,724,758.

https://patents.google.com/patent/US10724758B2/en

 

Presenting Author: Monem Beitelmal Qatar Environment and Energy Research Institute - Environment and Sustainability Center

Presenting Author Biography: Dr. Beitelmal is a Principal Scientist leading research efforts on energy efficiency, indoor environment management systems, and operational sustainability at the Qatar Environment and Research Institute (QEERI). He previously served as an associate professor of mechanical engineering with the Mechanical Engineering Department at Santa Clara University (2009-2013). Before joining SCU, Dr. Beitelmal spent eight years as a Research Scientist at Hewlett-Packard Laboratories in Palo Alto California. His research work at HP Labs covered various areas in energy, thermal management, and sustainability from smart thermal control in handheld devices and systems to data centers. He currently holds over 60 US-granted patents. Dr. Beitelmal is actively involved in developing and implementing energy-efficiency strategies and indoor air quality management programs for buildings. His work focuses on reducing the building operations' environmental impact while improving the comfort and well-being of occupants. He is a senior member of the US National Academy of Inventors and an Associate Editor with the ASME Journal of Engineering for Sustainable Buildings and Cities.

Authors:

Monem Beitelmal Qatar Environment and Energy Research Institute - Environment and Sustainability Center