To operate NASA’s lunar base, the Sandia National Laboratories is developing a microgrid to distribute electricity from a nuclear reactor.
Future lunar base. (Photo: Sandia)
The ambition to establish a permanent base on the Moon by NASA is part of the effort to prepare for crewed missions to Mars, posing enormous technical challenges. The lunar base is not only located over 1,000 times farther from Earth than the International Space Station (ISS), but it also requires entirely new problem-solving methods.
One of the biggest challenges is providing power to the base. Since astronauts will need to stay for two months at a time, the base must operate throughout the lunar night, which lasts for 14 days. This means solar panels are not a practical solution; therefore, a series of small nuclear reactors are being developed to work in conjunction with solar panels. However, the base will need a microgrid to transmit electricity, ensuring a consistent and stable power supply. The complexity increases as the base consists of two facilities: one for habitation and the second for mining and fuel processing located a few kilometers away.
According to the proposal, the microgrid at each facility will connect with each other, similar to the grid on the ISS, but will require some fundamental adjustments. For instance, Sandia researchers need to determine whether the microgrid will operate on direct current or use alternating current and convert it to direct current at the habitation site.
Another issue involves developing systems and software to coordinate electricity at the processing plant to maintain voltage stability even as demand fluctuates over periods ranging from milliseconds to entire seasons. To achieve this, Sandia has developed the Scalable Microgrid and control system design methods to study the energy demands and specifications of the lunar base. Their idea is to develop the control system first along with the specifications for energy storage, followed by components to meet those specifications.
“There are some very important differences between the microgrid on the ISS and the lunar base,” shared Jack Flicker, an electrical engineer at Sandia. “One of those differences is the geographical size, which is particularly challenging when operating at low voltage with direct current. Another issue is that as the system begins to expand, there will be more electrical devices and power distribution sources within the base. Sandia is considering a microgrid with multiple distribution sources for the long term.”
