Temperature and Humidity Monitoring in a Smart Home
Updated: Feb 27, 2019
There are two main variables that determine if a human being will feel comfortable in a specific environment: ambient temperature and the humidity content of the air. We all know that air conditioners and space heaters adjust temperature to levels than enhance human comfort, but humidity plays an equally important role – sometimes the air must be dried or humidified to achieve optimal comfort conditions.
Effects of High or Low Humidity
If there is excessive humidity, or lack thereof, human discomfort is certain. The specific type of discomfort depends on whether humidity is high or low, and how it interacts with ambient temperature.
When combined with low temperature, high humidity has a chilling effect – it increases the rate of heat dissipation from the human body.When combined with high temperature, high humidity has a suffocating effect – it does not allow sweat to evaporate effectively from human skin.
On the other hand, low humidity increases the rate of moisture evaporation from the human skin, and the resulting effect is a sensation of dryness and itching, which applies for both low and high temperatures.
The concept of relative humidity (RH), which is the ratio of water vapor in the air to the maximum amount possible that the air can hold at a given pressure and temperature, is more useful when dealing with human comfort. The RH levels recommended by HVAC organizations vary, but they generally fall between the range of 30% and 60%.
How Monitoring Can Enhance Comfort and Energy Efficiency
Space cooling and heating systems have traditionally used ON/OFF control based on a thermostat, but this approach does not provide the most efficient operation because relative humidity is not monitored, and temperature is sensed at a single spot that may not be representative of general conditions.
In order to optimize human comfort while minimizing energy consumption, an HVAC system must be equipped with:
A monitoring device, capable of measuring both temperature and relative humidity.
A smart cooling or heating unit, depending on the application. There are now air conditioners and heat pumps with variable-speed compressors that offer significant savings over units with ON/OFF operation. For example, running a fan at 80% speed offers 36% savings compared with running it at full speed for 80% of the time.
Thermal storage can also be included, which allows heating and cooling equipment to only run when energy prices are at their lowest. Cold storage tends to be better suited for commercial and industrial applications, and is not easy to scale down for the needs of households; however, hot storage is viable for all system sizes.
Temperature and Relative Humidity Monitoring for Hanover Housing UK
Hanover Housing is a UK-based developer and operator of retirement flats, apartments and bungalows, focusing on persons of age 55 or above. Hanover Housing has a strong focus on smart living, and has introduced several programs to reduce household expenses of all types, including energy bills.
Human comfort is important in all types of indoor spaces, but becomes particularly important in spaces inhabited by seniors, who may be more susceptible to health conditions brought forth by inadequate temperature and moisture conditions. Hanover wanted to ensure optimal indoor conditions at 15 of its properties, and contacted Logic Energy to deliver a monitoring system to keep track of the two key variables that determine human comfort: ambient temperature and relative humidity.
The system was equipped with GSM capabilities, allowing data to be accessed in real time through an Internet connection. Data is also backed up at a cloud-based server at regular intervals, providing an extra measure of safety