Israeli scientists harness lunar energy - through sunlight

On Earth, providing 100% of electricity demand 100% of the time solely from renewables, but without energy storage, is regarded as unattainable

 Photograph of a commercial PV array for space, comprising 3 modules of high-efficiency solar cells, each module being 1.1 m wide, dimensions that are commonplace for space missions. Around 30,000 such modules would suffice to power the expansive envisioned lunar colony. (photo credit: BEN GURION UNIVERSITY OF THE NEGEV)
Photograph of a commercial PV array for space, comprising 3 modules of high-efficiency solar cells, each module being 1.1 m wide, dimensions that are commonplace for space missions. Around 30,000 such modules would suffice to power the expansive envisioned lunar colony.
(photo credit: BEN GURION UNIVERSITY OF THE NEGEV)

How can energy be produced and supplied on the Moon if and when it is colonized by humans – as is being planned by NASA and several other countries’ space agencies? Can power from the sun be provided in an uninterrupted way without energy storage?

On Earth, providing 100% of electricity demand 100% of the time solely from renewables, but without energy storage, is regarded as unattainable. This Earth-bound mindset has been challenged recently by a paradigm shift developed by emeritus Prof. Jeffrey Gordon of the solar energy and environmental physics department at Ben-Gurion University of the Negev’s Blaustein Institutes for Desert Research in Sde Boker.

Presenting the evidence to NASA

Gordon was invited to present his case to NASA a few months ago. His idea was published earlier this year in the premier journal Renewable Energy.

On the moon, solar energy is the sole available renewable resource. The huge challenge is to completely supply the main energy consumer. Factories would need to continuously, 24/7, produce thousands of tons of oxygen (O2) per year from the lunar soil for rocket propellant, orbiting satellite refueling and human sustenance. A large part of the challenge is because, on average, every location on the Moon spends half of the lunar rotational period of 29.5 days in the dark.

 Photograph looking down on the Moon's north pole, restricted to 5° of latitude. The red dashed ring at a latitude of 87° contains the PV arrays. (credit: BEN GURION UNIVERSITY OF THE NEGEV) Photograph looking down on the Moon's north pole, restricted to 5° of latitude. The red dashed ring at a latitude of 87° contains the PV arrays. (credit: BEN GURION UNIVERSITY OF THE NEGEV)

"Our new strategy is more than a factor of 100 better than solar with battery storage. It is also at least a factor of six superior to the solution now being contemplated by NASA of nuclear reactors driving conventional turbines and generators.”

 Prof. Jeffrey Gordon

In his paper, Gordon documents a feasible strategy where uninterrupted electricity would be produced by photovoltaic (PV) arrays installed around a 360° latitudinal ring close to but not at a lunar pole, with transmission lines installed to the O2 plants for which there would then be substantial remote siting flexibility.

“My solution has a specific mass far below all alternatives so far, namely, record low kilogram/kilowatt – a key figure of merit for affordable and feasible lunar installations, with launch and installation costs currently exceeding $1,000,000/kg," he said.

"Our new strategy is more than a factor of 100 better than solar with battery storage. It is also at least a factor of six superior to the solution now being contemplated by NASA of nuclear reactors driving conventional turbines and generators.”

Gordon’s findings were published last March under the title “Uninterrupted photovoltaic power for lunar colonization without the need for storage.” He soon was invited to present his findings at NASA’s headquarters for solar power in space at the Glenn Research Center in Cleveland, Ohio. NASA scientists there said they were ready to rethink the plan to power lunar colonies with nuclear energy instead of solar energy, said Gordon.

The concept exploits the unique combination of the absence of a lunar atmosphere; the near-zero tilt of the Moon’s polar axis with respect to the ecliptic plane; lunar conditions being amenable to low-mass inexpensive transmission lines; and a lunar diameter far smaller than that of Earth.