Better Breathe Initiative Nepal (B2IN): Nepal’s first Satellite-Based Open-Source Air Quality Monitoring Network

Preface: 

Kathmandu, the capital city of Nepal, faces pressing challenges in public health due to deteriorating air quality. According to IQAir, the PM2.5 concentration in Kathmandu is 8.5 times higher than the World Health Organization's (WHO) annual guideline value. The AQI reaches “hazardous” levels during dryer seasons. The 800,000 residents of Kathmandu face an impending public health crisis. To address this issue from a policy-making level, data analysis of Kathmandu’s air quality trends is the first and the most essential step.

Project Summary:

Better Breathe Initiative Nepal (B2IN) aims to deploy a network of high-resolution Air Quality (AQ) and Composition Monitoring Sensors throughout Kathmandu Valley. The near real-time data acquired from the sensors is made fully open source through web-gis portal and API. These data will be crucial for monitoring real-time air quality while studying Nepal’s AQ trends, database, and conducting research. It will provide a base for private and governmental organizations to formulate efficient plans and policies. Data availability will also raise public awareness of the status quo.

Ground Sensor Terminal (GST):

The GST has a compact structure of roughly 100mm*100mm*50mm. It has two modules, the upper module and the lower module. The lower module houses esp32wl55, the main microcontroller of this system. It further has radio frequency components like LoRa and a GSM module, and other components like power management circuits, a battery, an SD card slot, a USB port, and switches. The upper module holds the sensor components like the high-resolution SPS30 sensor, air composition sensor, temperature sensor, and humidity sensor.

Data Reading and Logging:

The SPS30 sensor collects PM1, PM2.5, PM5, and PM10 data and the Alphasense AFE gas sensor collects CO and NO(x) readings. Humidity and Temperature measurements are also made along with their concurrent timestamps. Data is passed to STM32wl55 through the I2C bus which is stored in an SD card.

Using edge deep learning models, the GST can change data collection frequency. If a critical reading is recorded, the AQ-GST intelligently increases the recording frequency, making detailed, multiple readings of that critical time. Such optimizations increase power efficiency and provide better data visualization of air quality patterns of critical times.

Communication:

Nepalese nano-satellites arrive in the sky above Kathmandu for an average of 2 times a day. When it does, data is uplinked to the nano-satellites. It is then forwarded to the ground station and made available on the server through the backend. Concurrently if a cellular network is available, data is transmitted through GSM. Having two modes of data transmission reduces system redundancy in case of a system failure. In the best case, data from both mediums are cross-checked for verification.

Organizational summary:

Antarikchya Pratisthan Nepal (APN, estd. 2021, not-for-profit) has been involved in nano-satellite research and development, satellite data analytics for urban planning, disaster response, and educational outreach in Nepal for over 4 years. 

PCBWay has been the primary contractor of APN for all of our engineering projects in the past 4 years. This includes over 2 nano-satellites, satellite payloads, and ground stations accumulating to over 150 PCBs.

Support:

With support from PCBWay, we can optimize our designs, scale up the numbers, and ensure an impactful implementation of our idea. With greater support in manufacturing, we can further scale up our project by hosting air quality awareness programs, data analysis boot camps, and vocational GIS training for industries. 

Together, we believe that we can make the idea of air quality research, actions, and policies in Kathmandu a reality. It will positively impact the 800,000 men, women, and children who wake up to the hazardous air of Kathmandu daily. It will also lay the foundation of Nepal’s first-ever satellite-based open-source air quality monitoring network which can be scaled in neighboring districts that face similar health crisis!

Here’s to clean air quality access for all!