Categories: Design & Prototype
Can bamboo be used to remove carbon dioxide from the air, supply oxygen and be a structural material on the moon? What would the greenhouse look like when built for the moon?
The long-term goal for a lunar base is to develop mining and manufacturing capabilities. Making things that can be used on the moon and things that could be sent to space from the moon. Many people are hoping to mine water ice from the dark segments of the moon and be able to use it for oxygen, and for fuel for spacecraft that could be launched from the moon
One possibility is to mine materials from the lunar regolith. There are many metals and even oxygen that is in the regolith chemically. These can be difficult things to remove because of the amount of energy required to separate them from the regolith.
Another possibility is to use some of the materials that we take with us to the moon in ways that are helpful for the lunar base. People on the moon require a continuous supply of oxygen that is either brought from Earth or produced on the moon. They exhale carbon dioxide, a poison, which has to be removed from the air. CO2 has been removed from spacecraft in several different ways using various materials, including lithium hydroxide, zeolite, amine, metal oxide and a few others. All of these separate out the carbon dioxide from the air, but also remove a significant amount of water vapor from the air. We don’t like to lose the water.
Most methods release carbon dioxide out into the vacuum of space and thereby lose the oxygen that is contained within the carbon dioxide (along with some water). NASA has also used a Sabatier system that would mix the carbon dioxide with hydrogen and use a catalytic reaction to produce water and methane.
CO2 + 4H2 = CH4 + 2H2O
The water would be kept on the space station and reused. The methane would be released out into space. In the future, we might use this Sabatier system to produce methane as a fuel.
These are all complex systems that have to be repaired and have significant replacement parts. Another possibility for removing carbon dioxide is to use plants. Most plants in small numbers do not produce enough oxygen, nor remove enough carbon dioxide to be used in a small spacecraft and would require a very large volume. There are, however, several species of plants that photosynthesize large amounts of carbon dioxide and release oxygen back into the atmosphere. Bamboo has been studied extensively and is considered the most efficient at removing carbon dioxide from the air and turning it into plant fibers. Some bamboo can grow up to 2 feet or more in a day, implying that they are removing a large amount of carbon dioxide from the atmosphere. Growing two or 3 feet per day would obviously be a problem on a small spacecraft. However, if you have a large growing space on the moon, it may be possible to grow bamboo not just for carbon dioxide removal, but also to utilize the plant stocks as a structural material.
Growing bamboo has a number of benefits. CO2 removal, most bamboo shoots are edible, act as a structural material for construction on the moon but also the act of growing it is a mental health activity for the astronauts—a little bit of Earth on the moon. This Bamboo garden is not intended remove all of the CO2 but is intended to act as a back up to the mechanical and chemical systems.
Interested on working with this project? Invite your school, coordinate with NASA admins, and Get started!