Assignment 2: Sensor Tech for HVAC - Draft 2 (Summary & Readers Response)

In the article "The Expanding Role of Sensor in "Smart' HVAC Systems", Manz (2018) expresses the need for sensors in buildings as it will "reap significant energy savings". He explained that by connecting all the various systems in the building, especially the heating, ventilation, and air-conditioning (HVAC) system, will create an integrated and innovative monitoring software that observes the energy consumption of the building. Manz mentioned that over the years building owners neglected energy savings until the 1970s and 2000s when there was an increase in oil prices, making "power conservation is essential". Another aspect of the need for sensors is the advancement of technology. He mentioned that replacing the analogue sensors with a small-scale digital unit reduces installation time and "eliminate the need for recalibration". According to the article, sensors have changed the ways of energy management in a building. However, the author could have elaborated on the benefits of sensors in a smart building: determining the occupancy load in the room, monitoring the indoor air quality, and integrating with other systems in the building. 

 

With an aid of a sensor, the HVAC system can operate based on the occupancy level or load in a room. In a normal building, the HVAC system will operate at full capacity throughout the day according to a fixed timing. For example, it will operate from 7.30 am to 6 pm and about an hour of the day, the occupants in the building will be lesser. Since most of the rooms will be empty, it causing an unnecessary waste of energy to cool down the building. Using an occupancy-based HVAC control system, it regulates the thermal comfort in the room based on peak and non-peak hours in the day. The sensor will sense the occupancy in the room and "cool" down the room accordingly. If the room has been unoccupied after some time, the HVAC system will return to its preconditioned temperature setting maintaining the comfort level in the room. With an occupancy-based control sensor, it reduces the energy consumption in a building and ensures the coolness of the room is maintained.  

 

Secondly, we spend at least 90% of the time indoors compared to outdoors and we continuously breathe in "indoor air" which has been recycled multiple times throughout the HVAC system. Through this process, the number of pollutants in the air inside the system will start to build up and may irritate the eyes and nose. If the building has insufficient vent outlets and inadequate ventilation, it will contribute to short and long-term health issues such as asthma, pneumonia, and systematic hypertension. Through monitoring the level of carbon dioxide in the building, building managers can determine if the indoor air quality (IAQ) is well ventilated and able to circulate with the outdoor air, replenishing the oxygen in the building and clearing the pollutants within the building. IAQ is an essential part of the HVAC system as it manages the comfort level and increases the productivity of the occupants as well. 

 

Lastly, the current HVAC system uses a single propriety monitoring management but it does not monitor overall systems in the building such as lighting, fire system, security management. As technology advances, the possibility of integrating all the various building systems into a single management system. Such an example is an additional sensor that can be installed to monitor the sunlight intensity within the room and lower light settings accordingly, thus increasing energy efficiency. Future innovations of sensors are limitless and it will help to construct the building's design and function.

In conclusion, sensors within the HVAC system has been an asset in energy management and maintaining the overall occupancy comfort in the building. Without sensors, the building operations would be vastly different and it has eased our living conditions without realizing it.

 

References: 

 

1) Dong, Jin & Winstead, Christopher & Nutaro, James & Kuruganti, Teja. (2018). Occupancy-Based HVAC Control with Short-Term Occupancy Prediction Algorithms for Energy-Efficient Buildings. Energies. 11. 2427. 10.3390/en11092427. 

 

2) Aeroqual (2018, Sept 25) Why monitor indoor air quality? aeroqual.com/why-monitor-indoor-air-quality

 

3) Eric Germain (2011, Feb 2) The Benefits of Air Quality in Building Management https://www.envirotech-online.com/article/health-and-safety/10/sgx-sensortech/the-benefits-of-air-quality-sensors-in-building-management-eric-germain/864

 

4) Nick Searle (2018, April 4) Top five benefits of HVAC and lighting control integration https://www.csemag.com/articles/top-five-benefits-of-hvac-and-lighting-control-integration/

 

5) Coolautomation (2016, May 1) HVAC System – The Past, The Present and The Future https://coolautomation.com/blog/how-do-we-make-hvac-integration/ 

(Revised on 9 Oct 2020, Friday)