# Ensuring Energy Efficiency of Air Quality Monitoring Systems Based on Internet of Things Technology
## 5 Discussion
### Architecture of an Energy-Efficient IoT Air Quality Monitoring System
Putting the sensors to sleep during periods of inactivity also contributes to a significant reduction in energy consumption. The optimization of data transmission through the use of energy-efficient protocols and the minimization of the amount of data transmitted ensures the efficient use of energy resources. A typical low-power Zigbee gateway is equipped with an energy-efficient processor, a radio module with support for energy-saving modes, and a small display screen for displaying information. Due to these characteristics, the Zigbee gateway provides efficient data transmission and communication support between the components of an IoT system. Mini UPS (uninterruptible power supply) setups or small uninterruptible power supplies are becoming increasingly popular due to their portability and their ability to keep devices running smoothly in the event of a power outage. The choice of such a device largely depends on its energy efficiency, which has an important impact on the functioning of the system (Table 5). Among the main advantages of a Mini UPS is battery life. The less power the device consumes, the longer it is able to provide power to connected components during a power \begin{table}
\begin{tabular}{c c c} \hline \hline
**UPS Type** & **Advantages in Terms of Energy Efficiency** & **Disadvantages** \\ \hline Linear-interactive & High efficiency in normal operation & May have low efficiency, with frequent battery switching \\ Online & Stable output voltage, but high power & High power consumption \\  & consumption online & May cause damage to devices during \\ Offline & The most energy-efficient system, but it does not & May cause damage to devices during \\  & provide voltage stabilization & sudden voltage drops \\ \hline \hline \end{tabular}
\end{table} 
Table 5: Comparison of the different types of Mini UPS in terms of their energy efficiency. outage. Energy efficiency also contributes to increased battery life, as lower levels of stress reduce the battery degradation process. Reducing energy consumption has a positive effect on the cost of operation, thereby reducing energy costs. In addition, energy-efficient devices contribute to the preservation of the environment by reducing carbon emissions. The energy efficiency of the Mini UPS is affected by a number of factors, one of which is the type of battery. Lithium-ion batteries, which are often used in Mini UPS setups, have high energy density and efficiency. Modern charging circuits are able to optimize the charging process, thereby minimizing energy loss. The efficiency of the inverter also plays an important role, as it converts direct current from the battery to alternating current to power the devices. The higher the efficiency of the inverter, the lower the energy loss. The mode of operation of the Mini UPS is also an important factor: different modes (online, offline, or line-interactive) have different efficiency levels. For example, the online mode provides the best power stability but usually has higher power consumption. Additional features, such as a display or USB ports, can increase power consumption, so they must be considered when choosing a device. The energy efficiency of the Mini UPS is critical to ensure the stable operation of IoT air quality monitoring systems and minimize energy consumption. During the launching and testing of an air quality monitoring system developed based on Internet of Things technology, data were collected on the efficiency of the components, the accuracy of sensor measurements, the stability of communication, and the performance of the automated scenarios. An analysis of the system's communication stability and data transmission shows the following values:  
* The frequency of data updates from the Smart Air Zigbee (Manufacturer/company: GAOTek, New York, USA and Toronto, Canada) sensor via the gateway was 30-60 s.
* Packet loss in the Zigbee network was < 1% at a distance of up to 10 m from the gateway, indicating stable communication.