Water could propel satellites in future

An Indian start-up foraying into space technology is coming up with a propulsion system for satellites known as Microwave Thruster, designed to run on water as fuel medium.

The technology has zero erosion characteristics, thus, increasing the on-orbit lifespan required for a propulsion system.

"Microwave Thruster produces more thrust per kilowatt of power consumed, compared to most other type of electric propulsion," claimed Yashas Karanam, Director and Chief Operating Officer of Bellatrix Aerospace.

"Electric propulsion is different field that offers up to 10 times higher specific impulse than chemical propulsion systems for the same amount of fuel. An electrically powered spacecraft propulsion system uses electrical energy to change the velocity of a spacecraft," Yashas told to Indian Science Journal.

Using electric propulsion instead of chemical propulsion, manufacturers can reduce the overall satellite mass or otherwise accommodate up to four times more payload with the same satellite mass.

Satellite manufacturers have to pay huge launch costs to take their satellites to space, partially because rockets are expendable in nature. But electric propulsion would bring down the overall cost of satellite mission, said Yashas.

Yashas said, conventional chemical propulsion is not an attractive option for interplanetary missions, because there are no refuelling stations to refill the propellant. For future missions to Moon or Mars missions, electric propulsion is the only road to go.

They are now working to see that electric propulsion systems replace most of the chemical propulsion systems by 2025.

Electric propulsion is not a new concept. Work in this area had started in the mid 20th century.

Since power available now for propulsion systems is higher, satellites can use high power thrusters capable of delivering more thrust. This makes it possible for satellites to reach their orbit in four months, thus making electric propulsion a good choice for satellite propulsion.

Bellatrix is the recipient of the prestigious Technology Development Board National Award - 2017 for its innovative satellite propulsion design, for which it holds a patent.

With the advances in solar panel technology, solar panels today have achieved great efficiencies and can generate significantly higher power on satellites. Also, power consumption of various satellite sub-systems has reduced due to advances in electronics. This has provided more scope for electric propulsion.

The team is now looking to provide an economical alternative by developing its own small satellite launch vehicles. Named 'Chetak', the two-staged, reusable rocket can launch smaller satellites up to low-earth orbit at a fraction of the cost.