The hydrogen economy is expanding beyond terrestrial applications, with a growing number of startups targeting the space sector. These companies are developing innovative solutions for propulsion, life support, and in-situ resource utilization (ISRU) on the Moon and Mars. Their work is often conducted in collaboration with national space agencies, addressing unique technical challenges posed by the space environment.

One prominent area of focus is hydrogen-based propulsion systems. Startups like HyImpulse Technologies, a spin-off from the German Aerospace Center (DLR), are leveraging hybrid rocket engines that use paraffin and liquid oxygen. While not purely hydrogen-based, their work incorporates hydrogen-rich fuels to improve efficiency and reduce costs for small satellite launches. Another example is Orbitron, which is exploring green hydrogen as a propellant for orbital transfer vehicles, aiming to provide sustainable alternatives to traditional hypergolic fuels. The challenge lies in cryogenic storage and handling in microgravity, requiring advanced thermal management systems to prevent boil-off.

Life support systems represent another critical application. Companies such as OffWorld and SpaceFab are investigating hydrogen fuel cells for power generation in lunar habitats. These systems must operate reliably in extreme temperature variations and partial gravity environments. OffWorld has partnered with ESA to test regenerative fuel cells that combine electrolysis and fuel cell technologies, enabling energy storage during lunar daylight and power generation during the long nights. The primary hurdle is minimizing water loss in closed-loop systems, as hydrogen leakage in low-pressure environments can disrupt the balance of life-supporting resources.

In-situ resource utilization (ISRU) is a game-changer for sustainable space exploration. Startups like Lunar Outpost and ispace are working on extracting water ice from lunar regolith and splitting it into hydrogen and oxygen via electrolysis. These efforts align with NASA’s Artemis program, which aims to establish a sustainable presence on the Moon. The technical challenges include developing robust electrolyzers that function in low gravity and high dust environments. Additionally, the energy requirements for water extraction and processing are substantial, necessitating efficient solar or nuclear power solutions.

Collaborations with space agencies are crucial for these startups. For instance, HyImpulse has engaged with ESA’s Boost! program to advance its propulsion systems, while Lunar Outpost is part of NASA’s Commercial Lunar Payload Services (CLPS) initiative. These partnerships provide funding, technical expertise, and access to testing facilities, accelerating development timelines. However, regulatory hurdles and the high cost of space-grade components remain barriers to rapid commercialization.

A key differentiator among these startups is their approach to scalability. Some focus on modular systems that can be deployed incrementally, such as small-scale electrolyzers for initial lunar missions. Others aim for large-scale infrastructure, like hydrogen depots in low Earth orbit to support deep-space missions. The latter requires solving challenges related to long-term cryogenic storage and automated refueling in space.

The economic viability of hydrogen in space applications is still being evaluated. Launch costs, though decreasing, remain a significant factor. Startups must demonstrate that their solutions offer a clear advantage over conventional alternatives, whether in terms of cost, performance, or sustainability. For example, hydrogen’s high specific impulse makes it attractive for propulsion, but its low density increases tankage mass, offsetting some of the benefits.

Another emerging area is hydrogen-powered drones for planetary exploration. Companies like Astrobotic are developing lightweight, fuel-cell-powered rovers that can operate in the thin atmospheres of Mars or the vacuum of the Moon. These systems must be highly reliable, as maintenance or refueling opportunities are nonexistent once deployed.

The regulatory landscape is also evolving. International treaties and national policies on space resource utilization are still in flux, creating uncertainty for startups. Clear guidelines on property rights and environmental protections will be necessary to attract further investment.

Despite these challenges, the potential of hydrogen in space is immense. Its versatility as a propellant, energy carrier, and life-support resource makes it indispensable for long-duration missions. Startups are at the forefront of this innovation, bridging the gap between theoretical concepts and practical implementations. Their success will depend on continued collaboration with space agencies, advancements in materials science, and the development of cost-effective manufacturing techniques.

The next decade will likely see significant milestones, from the first hydrogen-fueled lunar lander to the establishment of propellant depots in orbit. These achievements will pave the way for a sustainable human presence beyond Earth, with hydrogen playing a central role. The startups driving this revolution are not just solving technical problems—they are shaping the future of space exploration.

As the industry matures, consolidation may occur, with larger aerospace firms acquiring promising startups to integrate their technologies. However, the agility and innovation of these smaller companies will remain vital in pushing the boundaries of what is possible with hydrogen in space. The race to harness hydrogen’s potential is well underway, and the winners will be those who can turn scientific and engineering breakthroughs into reliable, scalable solutions for the final frontier.