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Extraction of oxygen from lunar regolith using solar pyrolysis

Experimental apparatus of an experiment to characterize solar pyrolysis of lunar regolith simulant, a) Flowchart of the setup with the reactor, solar concentrating system and the various peripheral equipment, b) Picture of the pyrolysis reactor during sample exposure to concentrated solar energy. Note glass reactor clouding due to the deposition of the vaporized materials. Credits: Figure 2 with minor text edits from article by Jack Robinot et al. / Used under CC by 4.0

A team of European researchers have for the first time, quantified oxygen production via solar pyrolysis, a process that uses concentrated sunlight to heat lunar soil to release oxygen as a gas. Jack Robinot and collaborators report their results in Advances in Space Research. The findings of this study mark a significant milestone in space manufacturing technology, providing the first-ever direct experimental quantification of oxygen yield from the thermal decomposition of lunar regolith using focused solar energy.

As space settlement advocates are aware, the primary bottleneck for long-term human habitation on the Moon and elsewhere in the solar system is the logistical challenge of resupply of resources from Earth. They know that In-Situ Resource Utilization (ISRU) is the key to long term sustainability by harvesting and processing local materials into valuable resources like oxygen, water, and metals.

Oxygen is obviously of particular importance, not only because it’s needed for human life support, but also for rocket fuel. Liquid oxygen typically constitutes approximately 80% of the mass of rocket propellant. Producing oxygen directly on the Moon could dramatically reduce the cost of lunar and deep-space missions by eliminating the need to transport heavy fuel up from Earth’s gravity well. And of course it is a component of breathable air for settlers.

The lunar surface is covered in regolith composed mainly of silicate minerals and metal oxides. Despite the absence of an atmosphere, oxygen is the most abundant element on the Moon, making up about 45% of the regolith by weight.

When comparing the over twenty techniques that have been proposed for oxygen extraction—including carbothermal reduction and molten salt electrolysis—most require imported consumables like hydrogen or methane. Solar vacuum pyrolysis is advantageous because it:

  • Requires no consumables as it utilizes only solar energy and natural vacuum, both in abundance on the Moon.
  • Reduces logistics as there are no reagents to recycle or transport from Earth.
  • Lowers reaction temperatures because the low pressure of a vacuum environment favors the reduction of metal oxides, allowing the process to occur at more manageable temperatures.
  • Provides high efficiency via solar concentrators which can deliver high thermal power densities (up to 350 W/kg) without the energy conversion steps required by electrical systems.

By way of historical context, the concept of vaporizing lunar regolith was first explored in 1971 using samples of lunar soil returned by Apollo 12. Early researchers like Steurer (1982) proposed the theory of solar pyrolysis, calculating potential yields of 17%, but no solar experiments were conducted at that time.

Subsequent studies by Senior (1992) and Šeško (2024) successfully heated simulants and observed qualitative evidence of oxygen release, such as pressure increases or changes in material composition. However, technical challenges—including glass window breakage and the limitations of mass spectrometry—prevented these researchers from precisely quantifying the amount of oxygen produced. The current study bridges this gap by introducing a new analytical method using a trace analyzer to quantify oxygen within a carrier gas.

Before conducting experiments, the researchers modeled the behavior of heated lunar regolith through thermodynamic analysis of EAC-1 simulant (European Astronaut Centre-1, a high-fidelity lunar regolith simulant developed by the European Space Agency). They used the Gibbs energy minimization method via HSC Chemistry 10 (a process modeling platform widely used in the metallurgical and chemical industry). The model simulated the behavior of EAC-1 regolith simulant—which closely matches the oxygen content of real lunar soil (approx. 44%)—under temperatures up to 3000°C and pressures ranging from 10 mbar to 3 X 10-15 bar.

The key findings of the analysis included:

  • Temperature Dependence: At a pressure of 10-2 bar, the optimal reaction temperature was roughly 2600°C.
  • Pressure Impact: Lowering the pressure significantly reduces the required reaction temperature. At lunar surface pressures, the reaction could occur at temperatures as low as 950°C.
  • Oxygen Species: High temperatures and low pressures promote the formation of monoatomic oxygen (O), though this study focused on quantifying diatomic oxygen (O2).

The researchers noted that while the model provides a “target” for yield, it assumes a closed system at equilibrium. In practice, the experimental reactor will be an open system where species are constantly removed, shifting the equilibrium to promote further reduction via Le Chatelier’s principle.

Digging in to the setup and methodology, the experiments were conducted using a specialized solar reactor at the French national laboratory PROMES (Procédés, Matériaux et Énergie Solaire, or in English, Processes, Materials and Solar Energy), which is managed by the French National Centre for Scientific Research (CNRS).

The components of the apparatus included:

  • Solar Concentrator: A 2-meter diameter parabolic dish focusing sunlight into a 2 cm focal spot.
  • Tracking and Control: A heliostat provided real-time solar tracking, and a system of shutters precisely modulated the solar flux delivered to the sample.
  • Reactor Chamber: A glass vacuum sphere where the regolith pellet sat on a water-cooled steel holder.
  • Gas Analysis: An argon carrier gas was injected to sweep released oxygen into a high-precision oxygen trace analyzer (0.1 ppm to 1% range).
  • Condensation System: A refrigerated copper condenser and a porous stainless steel filter captured volatilized metal species to protect the vacuum pump.

The procedure was initiated by placing a 3.38-gram pellet of EAC-1 simulant in the reactor. The chamber was evacuated and then pressurized with 10 mbar of argon. Solar power was increased in stages with the following observations:

  1. 380 W: Initial melting was observed, but no oxygen was released.
  2. 650 W: A brief oxygen peak occurred, likely due to the reduction of volatile oxides like Na2O and K2O.
  3. 1200 W – 1460 W: Sustained oxygen production began as the sample reached approximately 1800°C.

The key results of the experiment achieved the first direct determination of oxygen reaction yield for this process:

  • Total Oxygen Extracted: 35 mg.
  • Mass Yield: 1.05% of the total processed sample weight.
  • Extraction Efficiency: This represents 2.47% of the total oxygen available within the regolith simulant.
  • Energy Yield: Approximately 31 mg of O2 per kWh.

The study observed that oxygen production happens in distinct stages: an early release during initial melting followed by a more sustained extraction period at peak temperatures. During the process, the vaporized material caused visible “opacification” (clouding) of the reactor’s glass window, which likely reduced the amount of solar energy reaching the sample toward the end of the run.

For characterization of the by-products, after the experiment the researchers analyzed the remaining residue and the deposits found throughout the reactor using SEM/EDS, XRD, and Raman spectroscopy.

With respect to mass balance, of the original 3.38 g sample, 1.82 g remained as a “glassy residue” on the holder, while approximately 1.1 g was vaporized and deposited elsewhere. The final mass recovery was 92%.

An elemental and phase analysis revealed:

  • Residue: Contained non-volatile elements like Aluminum (Al), Calcium (Ca), and Titanium (Ti), along with some Magnesium (Mg) and Silicon (Si).
  • Deposits:
    • On the holder: High concentrations of Sodium (Na) and Iron (Fe).
    • On the window: Primarily Silicon (Si) and Iron (Fe).
    • On the condenser: Mostly Silicon, with some Iron and Magnesium.
  • Crystalline Phases: XRD analysis of the original EAC-1 sample showed it was highly crystalline (containing minerals like augite, forsterite, and anorthite), whereas the residue present in the experiment was largely amorphous glass.

In the Discussion section of the paper the researchers found that the experimental yield of 1.05% was slightly lower than the 1.37% predicted by the thermodynamic model for conditions of 10 mbar at 1800°C. The discrepancy was attributed to several factors:

  1. Open vs. Closed System: The model assumes everything stays in the reactor, while the experiment continuously pumps gases out.
  2. Kinetics: Real-world reaction rates and temperature distributions within the pellet are not accounted for in basic equilibrium models.
  3. Argon Dilution: The argon carrier gas is a “double-edged sword.” While it allows for accurate quantification and prevents oxygen from recombining with metals, its presence increases the total pressure, which works against the pyrolysis reaction.

Although these numbers do not sound significant, the study demonstrates that solar vacuum pyrolysis is a viable, reagent-free method for extracting oxygen from lunar regolith. Beyond oxygen, the results suggest that fractional separation of metals is possible, as different elements vaporize and condense at different locations and temperatures. These findings are promising to inform follow-on studies to develop in-situ metal refining processes to provide feedstock for building lunar infrastructure.

Future work will focus on lowering operating pressures to further increase oxygen yield, customizing the reactor to allow for high carrier gas flow without increasing total chamber pressure, and development of advanced kinetic models that account for temperature gradients within the regolith.

By successfully quantifying the oxygen yield, this research achieves an important benchmark for designing the next generation of hardware intended to support a sustainable human presence on the Moon. Once scaled up, solar pyrolysis factories could supply breathable air in situ for hotels like those planned by GRU Space and other dwellings in communities envisioned by Lunar Cities, a StellarWorld company.

Illustration depicting a stroll down a boulevard with shops, cafes and restaurants in an underground lunar community called District 1 planned by the company Lunar Cities, which could be supplied with oxygen harvested from lunar regolith via solar pyrolysis. Credit: Lunar Cities

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Pale Red Dots on Mars

Conceptual illustration of two Pale Red Dot villages on Mars serviced by SpaceX Starships. Credits: Pale Red Dot Team*

Pale Red Dot is an acronym for Polis-based Architecture for the Long-term Exploration of the Red planet, with Exciting and Diverse Developmental Opportunities to Thrive. This concept, which was the first place winner of the NASA 2023 RASC-AL competition in the category of Homesteading Mars by a team* at the Massachusetts Institute of Technology Space Resources Workshop, focuses on establishing a city-state with Earth-independence supporting extensive scientific exploration on Mars. NASA’s RASC-AL (Revolutionary Aerospace Systems Concepts – Academic Linkages) competitions foster innovation of aerospace systems concepts, analogs, and technology by bridging gaps through university engagement.

This architecture envisions sending robotic precursor missions to Mars following experience gained from NASA’s Artemis program to survey sites, test technologies, and stockpile resources like water and propellant. Lets be honest up front that this paper is two years old and timelines for return to the Moon have been moved out. Predictions on milestones in the paper for this plan as described below should take these delays into account. With the current Trump administration the fate of Artemis program is evolving. There are many possibilities being proposed to streamline NASA’s plans, one of which by retired aerospace engineer and entrepreneur Rand Simberg, leverages public-private partnerships to get humans back to the moon. Keeping this in mind, when humans return to the lunar surface, Pale Red Dot would leverage the engineering knowledge gained from robotic landers and human missions used in Artemis or any subsequent initiative that emerges.

Next, in 2035 (at the earliest), robotic cargo SpaceX Starships would deliver approximately 5,800 tons of equipment consisting of habitats, nuclear microreactors, farming modules, manufacturing facilities, and in-situ resource utilization (ISRU) systems. By 2040, two crewed Starships would transport 36 colonists to Mars to establish two closely located villages. Costs would be shared by nations that are signatories of the Artemis Accords, 56 and counting as of this post.

The study used a modelling approach that prioritized safety and crew health in design of the architectures, both in transportation and surface facilities. Relying heavily on NASA’s current career permissible limits for space radiation, exposure was minimized by splitting the crew among two Starships, each one adding a 71-ton 35cm polyethylene shield, and dashing to Mars within 113 days. Upon arrival, to guard against galactic cosmic radiation and solar particle events, the initial surface habitats will have integrated 3m water tanks in their roofs for radiation shielding. The plans call for gradually building out radiation-proof underground tunnel habitats. Although not considered in this scenario, locating the settlements in a lava tube could be advantageous not only for ready-made radiation protection but thermal management as well.

The Pale Red Dot (PBD) architecture emphasizes robustness and thriving, rather than just survival, through substantial infrastructure supporting 36 crew members across two Martian villages. This includes extensive makerspaces and significant reliance on ISRU. The two nearby villages are designed to be energy-rich, water-rich, food-rich, time-rich, and capability-rich, with substantial self-rescue capabilities.

Diagram from Figure 4 in the paper depicting one of two villages of the Pale Red Dot architecture showing zone layout with modules for farms, habitation, mission utilization and makerspaces. Credits: Pale Red Dot Team*

The site chosen for the PRD settlements was based on a NASA Exploration Zone workshop in 2015. Called Deuteronilus Mensae, its situated near a glacier water source, in a hilly region that may be suitable for tunneling. More recent discoveries by the European Space Agency’s Mars Express orbiter, using its MARSIS radar, have revealed extensive water ice deposits up to 3.7 km thick beneath Mars’ equator in the Medusae Fossae Formation.

Extraction methods for sourcing in situ water were not addressed in the PRD architecture. This should not be a problem though as the communities could leverage methods that have already been validated, such as the RedWater System which could drill for, and collect, subsurface water ice.

The paper argues that such a large architecture, with its economies of scale and specialization, is crucial for mitigating the risks associated with a long-duration, minimally resupplied mission to Mars. Crew time modeling suggests that smaller missions with 12 or fewer people would not provide sufficient free surface traverse time for meaningful science and exploration. The estimated lifecycle cost for this campaign is $81 billion, with a peak annual cost of $6.6 billion.

The PRD concept highlights the potential for creating a true community on Mars with sufficient social complexity for humans to thrive. Furthermore, it proposes the geopolitically significant option of including crew members from every Artemis Accords signatory in the first human mission to Mars. Comprehensive details are provided on the dual-habitat architecture, concept of operations, mission control, technology roadmap, and risk burn-down plan.

* MIT Pale Red Dot Team Membership:

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Modeling an ISRU-based energy storage system for sustainable lunar electricity production

Illustration of a Lunar ISRU Energy Storage and Electrical Generation concept (not to scale). The system utilizes three heat transfer fluid circuits. The collection loop in the receiver tube is heated by sunlight from a field of mirrors during the lunar day and circulates to the thermal mass raising its temperature. Upon lunar nightfall, a discharge loop transfers heat from the thermal reservoir to the Stirling engine for electricity production. While the engine is running a thermal regulation loop dissipates heat through the radiator. Credits: system layout by Mario F. Palos and Ricard González-Cinca, modified to add component labels; lunar landscape by Grok 2

One of the difficulties of designing solar power systems for use on the Moon is the challenge of energy storage during the 14 day lunar night at lower latitudes far from the peaks of eternal light at the poles. Such systems would benefit from technology that leverages in situ resource utilization (ISRU) for this critical function rather then expensively transporting batteries from Earth. It would be ideal to model these systems prior to use via computer simulations to optimize the design before bending metal. In the journal Advances in Space Research, Spanish physicists Mario F. Palos and Ricard González-Cinca explore this approach in a paper that examines an ISRU-based system for energy storage and electricity generation.

The architecture of the proposed system, dubbed Lunar ISRU Energy Storage and Electrical Generation (LIESEG), collects solar energy during the lunar day via a mirror field to concentrate sunlight on a receiving pipe containing a heat transfer fluid (e.g. molten sodium). The heated fluid flows to a thermal mass raising the temperature of the energy reservoir. The resultant stored thermal energy from the reservoir is discharged through a second fluid loop used to drive a Stirling engine for electricity production during both day and night. A third heat rejection loop thermally regulates the system by transferring heat from the cold side of the heat engine to the radiator. This modular design balances efficiency and durability under extreme lunar conditions.

The ISRU implementation angle of the study emphasizes the use of lunar regolith and other local materials to minimize reliance on Earth-based supplies. This not only reduces launch costs but also aligns with long-term sustainability goals for lunar habitats.

To analyze the LIESEG system performance, simulations were carried out using EcosimPro software, a tool used by the European Space Agency in multiple aerospace applications, to assess power output, efficiency, and scalability. A comprehensive theoretical model based on the thermodynamics of the subsystems under lunar conditions was developed to analyze the energy flow and efficiency of the system. The study evaluated the specific power performance (power output divided by launch mass) of the system, highlighting its potential to be superior to other conventional methods like photovoltaic systems or nuclear reactors in terms of mass efficiency and sustainability. It also discusses the influence of key factors like the thermal conductivity of lunar regolith, the size and orientation of solar collectors, and the efficiency of the Stirling engine.

The authors conducted a detailed trade-off analysis of technologies, considering criteria like transportability, installation complexity, operational reliability, scalability, and lifespan. Solar collection and thermal conversion technologies were highlighted as critical components for achieving operational stability.

The proposed LIESEG system offers a promising approach for sustainable energy production on the Moon, potentially reducing reliance on Earth-launched resources and enabling longer, more autonomous missions. The system’s feasibility was demonstrated through computer modeling whose results show LIESEG to be practical for initial lunar missions with lower energy needs, as well as for later advanced bases requiring higher power outputs (up to 100 kWe and beyond). This research shows that a LIESEG system has merit for planning future development of energy infrastructure supporting initial lunar outposts and eventually, permanent settlements on the Moon.

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Offworld’s Prospector 1 mission to demonstrate ISRU on the Moon

Concept illustration of Offworld’s Prospector 1 Mobile Excavator. Credits: Dallas Bienhoff / Offworld, Inc.

At the intersection of AI, swarm robotics and mining technology lies the key to sustainable, affordable space development. Offworld, Inc. is on the cutting edge of this frontier with their suite of diverse robot species that when coordinated with collective intelligence, will enable sustainable in situ resource utilization (ISRU) thereby lowering the cost of establishing settlements on the Moon and beyond, while kickstarting a thriving off Earth economy. In a presentation to the Future In-Space Operations (FISO) Telecon on July 24, Space Systems Architect Dallas Bienhoff described Offworld’s plans for an ambitious demonstration mission called Prospector 1.

In April 2023, OffWorld Europe entered into an agreement with the Luxembourg Space Agency to collaborate on a Lunar ISRU exploration program commissioned by the European Space Agency. The multi-year initiative will develop a processing system focused on harvesting and utilizing lunar ice resources. The program will develop a Lunar Processing Module (LPM) to be integrated into a mobile excavator that will be launched to Moon’s south pole on the Prospector 1 mission currently scheduled for late 2027. The goal of Prospector 1 is to demonstrate the capability of processing icy lunar regolith to produce oxygen and hydrogen. The LPM when loaded with icy regolith will process the lunar soil to extract water, then via electrolysis produce oxygen and hydrogen. The module’s hopper is designed to receive up to 50 kg of regolith and batch process 2.5kg/hour. The unit will be housed on a mobile excavator massed at 2500 kg. Offworld has already completed TRL4 testing on the LPM in their Luxembourg office.

Offworld is evaluating several suppliers for delivery of their payload to the Moon. These include Blue Origin’s Blue Moon Mark 1 Lander, Astrobotic’s Griffin, Intuitive Machines NOVA-D and the SpaceX Starship.

The company is exploring a variety of options for generation of power for the mission. Of course landers provide some minimal power but not nearly enough for processing lunar regolith. One promising system under consideration is the Vertical Solar Array Technology (VSAT) under development by Astorbotic which will provide 10kw of power (only in sunlight). But wait, there’s more! Astrobotic announced this month that they were just awarded a Small Business Innovation Research (SBIR) award by NASA to develop a larger version of the array called VSAT-XL capable of delivering 50kw. Designed to track the sun, VSAT is ideal for location at the lunar south pole where the sun’s rays are at very low elevation and provide semi-permanent illumination on the rims of permanently shadowed craters.

Comparison of relative sizes of the two VSAT solar arrays. Credit: Astrobotic

Another innovative alternative is a power source called the Nuclear Thermionic Avalanche Cell (NTAC ) under development by Tamer Space, a company providing a range of power and construction resources for settlements on the Moon, the Cislunar economy and sustainable pioneering of Mars. The device is an electrical generator that converts nuclear gamma-ray photons directly to electric power in a compact, reliable package with high power density capable of long-life operation without refueling. NTAC can provide higher power levels (e.g. starting at 100kw) and is not dependent on the sun to enable operations through the lunar night should Offworld elect to locate their facility far from the Moon’s poles or in permanently shadowed regions. Tamer described their technology at the 2023 Space Resources Roundtable

Image of a research prototype of the Nuclear Thermionic Avalanche Cell: Credit: Tamer Space

After Propector 1, Offworld’s follow on plans envision a second Prospector 2 to be launched in the 2029 timeframe. This mission will ramp up capability to include multiple robot species such as an excavator, hauler, and processor. In addition, liquefaction will be added to the process stream (not just gaseous products) and pilot plant capabilities will be demonstrated to reduce risk for the next mission. In 2031, a formal pilot plant will be established with multiple excavators and haulers. The facility will have a fixed processing plant and storage facilities capable of producing tons of water, oxygen, and hydrogen. By the end of 2034, OffWorld plans to launch an industrial scale ISRU plant with output of 100s of tons of volatiles, elements and bulk regolith per year.

Bienhoff said at the conclusion of his presentation that Offworld’s long term vision for lunar operations include: “Industrial scale ISRU, 10s – 100s of tons of product per year – by product [I mean] that’s processed regolith, that’s oxygen, that’s hydrogen, that’s water, that’s perhaps metals. We plan to monetize or use every gram we excavate. That’s a tall order, but in order to have a thriving lunar community, we need to produce as much as we can on the Moon, for the Moon, before we think about exporting from the Moon.”

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South Korea goes for space-based solar power

Conceptual illustration depicting the design features of a Korean Space Solar Power Satellite (K-SSPS) Credits: Joon-Min Choi, Su-Jin Choi, Sang-Hwa Yi via Creative Commons License CC by 4.0

Researchers from the Korea Aerospace Research Institute (KARI) and the Korea Electrotechnology Research Institute (KERI) describe a concept for a Korean Space Solar Power Satellite in a new publication called the Journal of Space Solar Power and Wireless Transmission. Dubbed K-SSPS, its components would be launched with reusable rockets, robotically assembled and tested in LEO, then boosted to geostationary orbit (GEO) using solar electric thrusters powered by its own solar cell array.

The baseline conceptual design for K-SSPS provides 2GW of delivered power to the ground collected by a 4km diameter rectenna located in the Demilitarized Zone. There is sufficient space in this region for 60 rectennas of this size for a total collected power of 120 GW. In terms of electricity generation, such a system would provide a terawatt-hour of electricity per year which exceeds South Korea’s electricity consumption in 2021.

This study also addresses disposal of the system after its useful life estimated to be about three decades, Since such massive systems spanning an area measuring several square kilometers would present a rather large cross section increasing the risk of collision with other decommissioned satellites in the usual graveyard orbit located 235 km above GEO, the authors propose a novel but controversial approach: controlled crash landing the spent satellite in a safe zone on the far side of the Moon. This would enable future colonies on the Moon to harvest these valuable Earth-sourced materials from the impact zone, recycling them into useful commodities to help sustain lunar operations. Care would have to be taken to ensure that the structure is guided to a designated area far from established infrastructure, most of which (if not all) would be located on the near side facing Earth. Not considered in the study was recycling and/or repurposing the K-SSPS materials in space using material processing technology like Cislunar Industries’ Modular Space Foundry (previously Microspace Foundry).

South Korea’s space agency, the Korea Aerospace Research Institute (KARI), has set a goal of a test system deployment in LEO by 2040, with a full scale system in GEO by 2050. Since this effort will take considerable development time and significant financial investment, KARI plans a small-scale two-satellite pilot system demonstration in LEO within the next decade to validate the wireless power transmission technology and the deployment mechanisms. The pilot system, which was described in a paper presented at the 73rd International Astronautical Congress in September 2022, will be placed in a sun synchronous orbit and features a solar panel equipped antenna array beaming power to a receiver satellite 100m away, in a sun synchronous orbit.

Diagram depicting the operational concepts planned over the mission life of the KARI pilot space solar power demonstration. Credits: Joon-Min Choi, Su-Jin Choi, Sang-Hwa Yi via Creative Commons License CC by 4.0

KARI and KIRI have described their case studies on a space solar power program as a renewable energy option for Korea to help address global efforts to achieve net zero greenhouse gas emissions by 2050. This paper summarizes their concept design for a 2GW space solar satellite highlighting gaps in the economic and technological knowledge needed for success, proposed a responsible and sustainable disposal method, and outlined an achievable architecture for a near term pilot demonstration within a decade. Korea joins other global development efforts that SSP has been following with their own unique approach to space-based solar power (SBSP).

However, doubters have been surfacing recently highlighting the significant engineering and economic challenges that need to be addressed for SBSP to be competitive with ground-based renewable energy sources and backup storage systems, the technology of which are rapidly developing and improving. One skeptic, former European Space Agency engineer Henri Barde, published an article in IEEE Spectrum arguing that among other things, designers will have a significant challenge shaping and aiming the microwave beam of a kilometer-scale phased array antennae. In his opinion, this and other engineering obstacles will not be solved until fusion energy will be commercially available. In a rebuttal on LinkedIn, CEO of SBSP startup Virtus Solis John Bucknell responded that his company has proprietary software that can simulate greater than 2km transmission apertures and that SBSP is in the engineering phase while fusion is still in R&D, the complexity of which makes capital and operating costs a big unknown for commercialization.

NASA has yet again kicked the can down the road, claiming in their most recent study that expected greenhouse gas emissions and the cost of space hardware for current design options will be on a par with existing renewable electricity technologies and therefore recommends further study to close several technology gaps for SBSP to make economic sense. The next few years will be critical for engineering testing, not only for Korea’s pilot satellite, but Virtus Solis‘s in-space plans and Northrup Grumman’s end-to-end test in 2025 of their Space Solar Power Incremental Demonstrations and Research prototype system. Once in-space prototype testing demonstrates sufficient feasibility to retire technical risks, venture capital investors may feel comfortable funding subsequent operational phases toward profitable commercialization.