Sustainable Energy for Colonizing Mars
How can we use what we learn about settling a resource-sparse planet, like Mars, to gain appreciation and develop strategies for sustaining energy sources on Earth?
How can we use design, build and test automated sense and response systems in order to conserve energy and resources?
Understanding our Needs:
Students have started to brainstorm some ideas for what it will mean to colonize Mars with respect to energy sources. We were fortunate to have Ross Lockwood, engineer and former participant in the HI-SEAS program, come and speak to our grade 9 students about his experience. He focused on how they conserved energy and resources throughout their experience. This got students thinking even more about aspects they hadn't considered such as bathing with warm water! How will we maintain basic human needs such as hygiene when colonizing a planet with very limited water resources, especially when we will need water to also sustain gardens for our food supplies?
Tomatosphere Martian Gardens:
In September grade 9 students started the Tomatosphere germination phase of their experiment and recorded data for 39 days to determine if there was a difference in germination rate for tomato seeds that had spent 5 weeks in space. While our results were slightly different than that of the National results, both sets determined there were no significant differences in germination rate.
We have now started the next phase which is to transplant the tomato seedlings into pots containing the following proportions:
1/4 Mars:3/4 Earth
1/2 Mars:1/2 Earth
3/4 Mars:1/4 Earth
Because last year we noted that the best results came from plants that had been grown in a combination of Earth and Mars regolith, we decided to test proportions to see if we could find out if we could use a small amount of Earth soil to supplement the Mars regolith.
Students are working in groups to each track 3 plants using their own Google sheet that they have engineered to best compile their data. We are also growing a set of each soil ratio under magenta LED grow lights to compare to natural light.
Mars Garden Results:
Initially our plants grown under magenta LED lights initially appeared to be growing stronger and quicker. Their stems were thick and sturdy, while the plants in the windows needed to be supported by stakes. The LED plants also produced flowers much sooner, leading to many conversations about why the plants seemed to be doing much better than their natural light counterparts.
Was it the temperature close to the window? The fact that the LED plants got 10 hours of light each day while the ones in the window received far less in our dark winter months?
Eventually, however we started to notice that the plants under the light were changing colour and many leaves started to die off. Each plant produced a single tomato, perhaps in a last-ditch attempt to reproduce before the end of its life.
The plants in the windows started to thrive as warmer temperatures and longer days arrived. Not surprisingly, the plants with the highest ratio of Earth soil grew taller and produced more flowers and fruit than those in more Martian pots.
Automated Sense and Response Systems:
In order to both conserve resources and learn more practical applications from our Electrical Principles and Technologies unit, students worked with micro:bits and block-based coding systems to design automated sense and response systems.
We started by coding and setting up automated watering systems thanks to the hard work of Amanda Green and her students at Ecole Champs Vallee. We used their source code and the materials we purchased thanks to Inside Education and APEGA to make systems that could water plants automatically.
Once they'd experienced success with this, we brainstormed other potential systems that could be coded using the variety of sensors, lights, buzzers, etc that we had been able to accumulate thanks to our grant funding. Students were given free-reign, within the confines of the sensors and materials we have available to us, to decide which variable they wanted to design a system around.
The end results have been fantastic! We have watering systems, lighting systems, CO2 and temperature warning systems, even a fire suppression system! It was incredible to watch students test and redesign and collaborate in such an authentic setting!
Energy Resources on Mars - Solar Energy:
Unfortunately our solar energy test kits didn't work for our purposes, however that did not stop our adventure in powering systems using solar energy. Initially we started trying to power micro:bits directly with solar cells. Unfortunately, even with ample current and voltage, the micro:bit would not work. After reaching out via social media, we determined that the variability in current from the solar cell likely caused a problem with powering the bit. It was suggested that we find a solar manager, a small device (pictured below) that would supplement any variability in current using a rechargeable Lithium ion battery. The manager would draw from the solar cell first, use the battery as needed and even recharge the battery from the solar cell if there were sufficient solar energy.
You can imagine the EUREKA moment when the micro:bit lit up once connected! We could now use solar energy, at least in part, to power our systems. As a result, most groups have powered at least a portion of their systems using solar energy.
Students designed watering system powered in part by solar energy.
Micro:bit connected to solar manager system.
Solar Manager
Groups were required to complete templates that showcased their understanding of the electrical components and circuitry in their systems, as well as the energy transformations that were taking place throughout. They also had to include their code that was written to control the system.
Energy Resources on Mars - Biofuel:
Using a biofuel teaching kit, students learned about how biofuel is made through fermentation and observed simple experiments to determine the amount of energy available from each type of fuel per gram burned.
Emissions Determination:
In order to see how changing power sources would impact greenhouse gas emissions, we performed some simple experiments to both qualitatively and quantitatively observe any changes.
First, students looked at the residue left on the aluminum cans after the fuels were burned for 5 minutes.
Next we used a CO2 sensor, coded with a micro:bit, to quantify CO2 in ppm after the lamps burned for 5 minutes in an enclosed space.
We used the data we collected to determine the ppm CO2 emitted per gram of fuel burned for ethanol and for kerosene.
Next, we calculated the power available per gram of fuel in Watts and then used this to find a ppm CO2 value per Watt for each fuel.
This value was then used to determine how many emissions would be reduced when powering our devices using solar energy vs either of the two fuels.
Residue left from burning ethanol (left) and kerosene (right).
