ISRO set to launch its first fully Electric-propelled Satellites in December 2024

By R Anil Kumar

• The Technology Demonstrator Satellite (TDS-1), to be launched in December 2024, marks a significant milestone in India’s advancement in satellite technology, particularly with the development of an indigenously built Electric Propulsion System (EPS)

• The test will feature Indian made Electric-thrusters and travelling wave tube amplifiers, which helps enhance Satellite functionality and efficiency.

Bengaluru, October 31. India’s Space Agency, Indian Space Research Organisation (ISRO), is gearing up to test its indigenously developed Electric Propulsion System (EPS), for Satellites, this December. This is an innovation that reduces Satellite weight, thereby reducing fuel usage and enhancing Satellite functionality.

ISRO Chairman S Somanath announced this during Sardar Patel Lecture, recently, and stated that, this will be the Country’s first test of Electric Propulsion in a fully indigenous setup, showcasing advancements that could set the stage for efficient Satellite launches.

TDS-01 will feature Electric Thrusters that is developed entirely in India, a departure from previous systems that relied on imported technology such as the Russian system used in the GSAT-9 Satellite launched in 2017.

The Electric Propulsion System, helps reduce fuel requirements. Traditionally, a 4-tonne Communication Satellite would need around two-tonnes of liquid fuel. With EPS, this drastically reduces to 200 Kilograms of propellant gases like argon, ionised using solar power. This reduction in fuel requirement not only lightens the Satellite but also minimizes the size of its peripheral systems.

While Electric Propulsion offers greater fuel effiency and lightens Satellite, it generates lower thrust compared to chemical propulsion. Consequently, reaching geostationary orbit may take up to 3 months, significantly longer than one-week required by chemical thrusters.

In addition to Electric Propulsion Systems, TDS-01 will incorporate Travelling Wave Tube Amplifiers (TWTAs), which are essential for enhancing Communication and Remote sensing capabilities. The successful deployment of these amplifiers will represent a notable achievement for Indian Space Technology.

The launch of TDS-01 is a pivotal step for ISRO, demonstrating India’s capability to develop advanced Satellite technologies that are not only efficient  but also reduce operational costs and complexities associated with traditional Satellite designs.

EFFICIENCY GAINS FROM EPS

As known, Traditional Satellite Thrusters require significant quantity of liquid fuels primarily to shift from a launch orbit to geostationary orbit and to maintain position against gravitational shifts, while Electric Propulsion drastically reduces this requirement, thereby allowing for a lighter Satellite structure.

LOW THRUST DRAWBACKS

While Electric Propulsion reduces the fuel requirement it generates significantly lower thrust compared to Chemical-based Systems, thereby requiring longer time duration to reach the intended Orbit.

NISAR SATELLITE PROGRESS

In addition to TDS-01, ISRO is also preparing for the launch of NASA-ISRO Synthetic Aperture Radar (NISAR) Satellite. This collaborative mission between NASA & ISRO aims to monitor various environmental phenomena, including ecosystem disturbances, deforestation, icesheet collapse and so on. Somanath also stated that work on the Satellite’s radar antenna reflector has recently concluded, with the component now en-route to ISRO’s Spacecraft integration and testing facility, in Bengaluru.

Somanath said that integration of  Radar antenna reflector with the Satellite will take around two months and added that the Mission launch is slated for February 2025.