Welcome to “Beyond the Grid,” our exclusive Q&A series where we explore the pivotal role of power in space. In each interview, we bring you insights from leaders driving innovation in space technology. Today, we’re joined by Matt Kaplan, Analyst at Shield Capital, a venture firm dedicated to backing cutting-edge companies that are solving critical challenges in the space industry, including the ever-growing need for reliable power.

The Power Challenges in Space

Q: One of the critical challenges in space today is providing reliable power. What makes this such a significant issue for the space industry?

Matt Kaplan: Power is one of the most critical elements of any space mission. Whether it’s satellites, space stations, or even future lunar bases, everything depends on power. Solar power has been the go-to solution for satellites, whose solar panels capture the sun’s energy to power their missions and maneuvers. But scaling this for larger constellations, future moon missions, and even Mars is incredibly challenging, because as the cadence of satellite launches has increased, the supply of the solar cells that are attached to those satellites can’t keep pace. Those solar cells must be reliable, cost-effective, and capable of withstanding the harsh conditions of space, particularly radiation.

Geopolitical Impacts on Space Power

Q: Are geopolitical tensions affecting this critical challenge?

Matt Kaplan: Yes. The geopolitical landscape is significantly impacting the space power supply chain.In just one example, today we’re reconciling with the fact that China controls the supply of many of the world’s critical minerals. One that’s less often talked about is Gallium. For the last several decades, only Gallium Arsenide (GaAs), also known as “Triple Junction” cells, have been the go-to solar cells for space applications. For years, we haven’t had enough of them.
China mines about 98% of the world’s Gallium supply. And you usually want to co-locate mining and processing, so in reality China has a hold on the supply of Triple Junction solar cells. Aware of how important Gallium is for solar cells and other applications, China placed export controls on Gallium just last December. Again, Gallium Arsenide cells are used across the industry. Lack of reliable access means longer lead times, which means missions are either delayed or possibly cancelled altogether.

The Role of Solar Power in the Future of Space

Q: Solar power has been the mainstay for space missions. How do you see solar technology evolving in the next decade to meet the challenge you just described?

Matt Kaplan: Solar power will remain a crucial part of space missions. At some point, we may see alternatives like nuclear, and we’ve seen what are called Radioisotope Thermoelectric Generators (RTGs) used for deep space missions, but the industry predominantly relies on solar power. The technology – particularly the solar cells themselves – will need to evolve to meet the demands of a rapidly growing industry. The main alternative to Triple Junction cells is silicon cells, already used terrestrially. The challenge is that silicon hasn’t traditionally been as efficient or radiation resistant as the Triple Junction cells. SpaceX actually uses silicon cells for Starlink satellites, but they’re able to use significantly larger panels to make up for the performance loss. We will need silicon cells that can actually compete with or match the Triple Junction cells’ efficiency if we want to keep up with the expansion of satellite constellations in LEO and future missions to the Moon, Mars, and beyond. Advances in materials science, such as new solar cell architectures and improved energy storage solutions, will also be key in addressing these problems.

Scaling Power Solutions for Space

Q: With more companies entering the space sector, how important is scalability in the power solutions used for satellites and other space missions?

Matt Kaplan: It’s absolutely critical. As space becomes more commercialized, we are seeing an explosion in the number of satellites being launched (no pun intended). This explosion will continue as more mega-constellations come online for global communications and remote sensing, and we continue to see other new markets emerge. The power infrastructure that supports these missions needs to scale efficiently to meet the needs of thousands of small satellites, as well as larger satellites, all while maintaining cost-effectiveness and reliability. This is where innovations in solar cell manufacturing, energy storage, and eventually even alternative power sources like nuclear will play a role in meeting demand.

Securing U.S. Leadership in Space

Q: As geopolitical tensions rise, how do you see the need for energy independence in space affecting the broader U.S. space strategy?

Matt Kaplan: The need for energy independence in space is becoming more critical as space becomes a more contested domain. The U.S. needs to ensure that we have control over the underlying components that power our missions, not just the end platform. That means developing resilient, domestic supply chains to power our space assets without being dependent on materials or technologies controlled by the very country whose efforts in space we must compete with. Controlling our supply chain must be an essential part of our broader strategy for the space domain. We can’t remain competitive otherwise.

Eventually, energy independence in space will also be about more than just solar panels for satellites. It’ll also mean energy generation on the Moon and one day Mars, which will bring with it a whole new set of challenges and opportunities. On these celestial bodies and beyond,  as on Earth, energy will be critical infrastructure for any commercial, national security, or exploration mission.

The Future of Space Power

Q: Looking ahead, what excites you the most about innovations in scaling power for space and its applications for the broader space economy?

Matt Kaplan: Two things excite me most: the infrastructure buildout itself and what it will unlock.

First I’ll mention the infrastructure buildout by giving you a terrestrial analogy. Today, we’re undertaking a massive data center buildout on Earth to support growing compute needs from AI, and we’re seeing investments across the whole enabling stack – real estate suitable for hosting a data center, energy infrastructure including nuclear and solar, new cooling solutions like liquid cooling, software that optimizes how we allocate inference workloads across data centers, and much more. We’ll need the same level of disruption across the stack in space, and we’re just starting to uncover what that looks like.

The second thing is obviously the applications that infrastructure will enable. In the near term, we need to scale space power just to meet the demand we’re seeing today for more satellite launches for applications in remote sensing, communications, logistics, and more. In the long term, it’s sustainable lunar bases, manned missions on Mars, and deep space activities. Solving the space power problem will be key to unleashing the full potential of the space economy today and for decades to come.

Matt Kaplan’s insights shed light on the complex challenges and opportunities in space power, from geopolitical supply chain issues to the future scalability of solar technologies.

Stay tuned for more in our “Beyond the Grid” series, where we continue exploring the future of power in space. Follow us on LinkedIn to get the latest interviews and updates on groundbreaking advancements in the final frontier.