IoT Platform Development for a Solar Tracking System

About the Customer:

• Our client, the Indian subsidiary of one of the Global Pioneers in Renewable Energy Generation, had a mandate to improve the efficiency of their existing open field deployments of solar panels.

Business Challenge:

• The customer had deployed thousands of solar panels on the field. They wanted to increase the overall output by ensuring 100% alignment of the solar panels with the trajectory of the Sun (throughout the day).
• This increase in the generated power was expected to translate into an improved RoI from the open field deployments.

Why was the existing solar energy tracking system not efficient?

• The existing solar tracker, that was designed to harvest energy throughout the day, was following a single trajectory. Such a trajectory meant that the orientation of the solar panels (payloads) was not optimized as per the changing position of the Sun from dawn to dusk.
• As a result, the estimated annual power generation numbers were not as per the expectations.

What was required to achieve the desired RoI from the field deployments?

A network of Sun-Position Algorithm (SPA)-based solar trackers had to be designed to ensure efficient harvesting of the Sun’s energy from dawn to dusk.

Additional limitations of the existing solar trackers:

• The customer had a limitation with their existing solar trackers – Each tracker could manage only one block of PV-panels.
• The customer also required a second block of PV-panels to be monitored using a single tracker.
• This was necessary to ensure reduction in capex and increase system utilization.

The client realized that such a solar tracking system could be designed based on the architecture of Industrial Internet of Things (IoT) and would require expertise in wireless communication protocols, embedded software, hardware design, cloud application and web application development.

After multiple technology workshops and design sessions, our customer developed confidence in the experience and expertise of our IoT developers, designers and Industrial Automation experts.

This marked the beginning of our long-term and successful partnership with the customer.
 

Embitel Solution:

Our IoT and Industrial Automation teams developed the hardware & software for the embedded control systems that were integrated with Solar Panels.

Following are the details of the IoT project:
 

IoT platform development for network of solar trackers:

• The solar panels were connected to solar trackers (controllers) that changed the orientation of the panels based on the movement of the sun. The motion of the solar panels was regulated by the following input details:
  • Time of the day
  • Time zone
  • Location of the panel (based on GPS coordinates)
• Our team also designed an IoT platform solution for a network of solar trackers. This IoT based solar tracking system communicated through ZigBee and WiFi wireless protocols and serial communication interfaces.
• Our hardware design ensured that a network of eight solar trackers can be integrated on a single hardware board.
• An IoT-enabled master-slave network was designed, wherein a master controller controls up to 24 slave trackers. This master controller also sends consolidated data to the centralized server.
• We partnered with the customer for end-to-end design and development of the hardware board and firmware software for this Industrial Automation project.
• The embedded hardware for the Sun tracking system is designed on NXP micro-controller LPC1768 platform.
• The custom-built Industrial IoT gateway device is a linux based system designed on Atmel SAM A5 platform.
• Device drivers for all serial communication are RS-485 based half duplex as well as full duplex systems.
• Communication interfaces between master-slave solar trackers have been designed using industrial grade ModBus Stack.
• A mesh network, designed using the XBee modules, serves as the primary mode of communication between the master device and the tracker devices.
• A fallback communication channel has been developed for XBee connectivity, using the RS-485 communication link.

Embitel Impact:

• The designed IoT solution successfully achieved all the objectives of our customer. It addressed their main concerns of efficient power generation and monitoring.
• The Industrial IoT (Internet of Things) platform also helped reduce the cost of field operations.
• Our customer was able to increase their field coverage, including the irregular corner and fringe boundaries.
• There was more than 20% improvement in power output of the plant.

Tools and Technologies:

• OrCAD design tools for schema development, HyperLynx– Signal Integrity, Power Integrity, and Thermal Analysis.
• Atmel Linux development tool for the master board and Xpresso Eclipse IDE plugin for the tracker boards.
• ModBus over RS-485- ModBus Stack in Master mode from Silas.
• QT framework for PC-Application and ATS.