By Venkatachari Jagannathan Chennai, June 30 : The Indian government, while encouraging the private players to play a good part in the space sector with policy reforms, will continue to focus on research and development (R&D) on green fuel, robotic space exploration and reusable rockets, states the draft National Space Transportation Policy. The draft policy states focused research is essential on new propulsion systems based on semi-cryogenic, liquid oxygen-methane and green propellants. The Department of Space (DOS) under Government of India has recently come out with its draft National Space Transportation Policy. Its space arm -- Indian Space Research Organisation (ISRO)-- is working on green fuel (for rockets and satellites), human space missions and others. Similarly, private rocket makers are also for green fuel. The DOS Secretary and ISRO Chairman K.Sivan said the space agency is looking at green propulsion through hydrogen peroxide in its rocket that would take Indians into space under its 'Gaganyaan' mission. ISRO is also looking at rocket engines powered by hydrogen peroxide as a mono-propellant or as a bi-propellant along with ethanol. The Indian space agency is also developing another green fuel -- LOX/Methane -- liquid oxygen as oxidiser and methane as fuel. Sivan had told IANS that the test results were good for LOX/Methane engines. The LOX/Methane propellant has advantages in terms of specific impulse, storability, low toxicity, and cost. According to Sivan, the space agency is looking to replace its existing liquid engine fuels with green fuel-powered ones. ISRO has also developed ISROSENE, which is a rocket-grade version of kerosene as an alternative to conventional hydrazine rocket fuel. Queried about the green option for its solid fuel-fired engines, Sivan had said the work towards this end is also progressing well. As regards powering the satellites, ISRO is working towards lightweight electrical propulsion in place of chemical fuel. The private rocket makers are also moving towards greener fuel. "We are shifting to a greener cryogenic fuel (LNG) for our rocket's upper stage. We already manufactured an engine with this fuel and are in the process of testing. And this greener fuel will also fuel all our future vehicles," Skyroot Aerospace's Co-Founder and CEO Pawan Kumar Chandana told IANS. As regards other stages/engines Chandana said: "We will go with solid fuel as it's low cost and gives large thrust. Eventual plan is to shift to greener fuels for our future vehicles." According to the draft policy, it is essential for the DOS to work towards advanced space transportation capabilities including new propulsion systems, reusability as well as heavy lift capabilities to undertake robotic/human space exploration. In order to enable missions like human spaceflight, robotic space exploration, the draft policy states, the current capabilities of DOS/ISRO have to be significantly enhanced towards heavy lift/super heavy lift and reusable space transportation systems along with associated infrastructure, to enable access to low earth orbit and beyond. According to the policy, research should also be on development of more powerful rocket stages employing clustered engines that require a series of tests and the establishment of associated test facilities towards the validation and qualification of these systems. These developments may require new materials along with state-of-art design and manufacturing paradigms like additive manufacturing, which need to be explored through prototype validation and relevant facility establishment, the draft policy states. (Venkatachari Jagannathan can be contacted at v.jagannathan@ians.in) /IANS