From the Sun to my Screens

By Su Wild-River

This post was first published at:

I recently completed a Massive On-Line Open Course (MOOC) called “Dynamic Earth” through the University of Toronto. And in case you are wondering whether science can be taught through MOOCs, consistent with the pedagogical analysis presented by MOOC providers, I’m giving you a glimpse into MOOC world here.

The course’s ‘peer reviewed assignment’ was a 300 word essay anonymously assessed by three other randomly selected students who have also received a marking rubric and examples of papers of varying quality that have already been graded by professors.

The topic for this assessment was to trace the likely path from the device on which we view MOOC study material, back to the original astronomical source of energy – ie some form of solar energy. Is this science? Is it science communication?

Here is my response to the assignment topic – from the Sun to my Screens

“Fossil fuels are an input to all of the devices that feed MOOC materials into my brain. Those devices include a computer at The Australian National University (ANU), a home computer, and iPad.

My computer at The Australian National University (ANU) and my home electricity system are connected to the Eastern Australian electricity grid (EAEG), which sources mostly coal-fired electricity. The coal is burned to release heat which boils water to turn turbines and generate electricity, which is then transported through the grid to my computer. The coal issourced from plants that grew 200-300 million years ago and used solar energy for photosynthesis, converting carbon dioxide to cellulose. They then compressed into coal due to overlying sedimentation in a process fuelled by solar driven wind and water systems. Burning coal for electricity is inefficient and releases terrestrial carbon dioxide back into the atmosphere, unbalancing the earth’s dynamic atmospheric system and causing dangerous global warming.

My devices are also powered by a small amount of hydroelectricity and wind energy with fewer damaging impacts. The wind occurs because the sun warms the Earth’s surface, particularly at the equator. The Earth’s rotation and Coriolis Effect drive a pattern of wind across the world. Rain captured in the Snowy Mountains hydroelectric scheme falls there because low pressure systems are blown across Australia by Southern Hemisphere Westerlies. Water evaporates from the Southern and Pacific oceans and is uplifted in the low pressure systems, cooling and causing precipitation as the lows spiral clockwise across the Snowy Mountain Range. The rain is stored in dams high in the landscape, and then released under gravitational pressure to turn turbines that generate hydroelectricity. The Westerly winds also power turbines within the EAEG, generating electricity from wind.

At home I use a desktop computer, and charge my iPad to access this MOOC. Most of that energy comes from a solar array on my roof. Solar electricity is a more sustainable alternative to coal-fired power because it uses solar radiation directly from the sun, and there is no additional atmospheric pollution once the systems are installed.

I also use by brain to access this MOOC. The final energy pathway is the food I eat to power my brain and body. I grow about a quarter of my own food, mostly using the glycogen and glucose produced in my body by my digestion of that same food as the power source. The other half of my food is shop-bought, and I try to keep the food miles and other fossil fuel energy inputs down by buying fresh and local, with minimal packaging. The plants that I eat use photosynthesis to transform sunlight, nutrients and water into delicious cellulose. My brain is digesting the course material, and instructing me to work at home, using my solar energy systems.”

I received 26 out of 27 from my peer reviewers – so I was pretty happy with that. I also received the comment “You’re not a student, are you? That is the best and most extraordinary answer I have read so far. Thank you and God bless!” which I found rather enchanting.

I was however, somewhat disturbed when it came to my training in how to mark others’ assignments. I was given three assignments to mark as a test run – to calibrate my marks with those of the professors. The first one received 8/9 from me, but only 3/9 from the professors. The MOOC program instructed me to review the rubric. The second was better. I gave it 3, and they gave it 2 but I was still asked to review the rubric. I thought the third example was logically flawed and gave it 2, while the professors gave it 9. The next screen congratulated me on completing my training and started directing me to mark others’ work.

I enjoyed the marking process although I was nervous about the quality of my marking. I marked one from a remote area of Russia, and was fascinated to read about the landscape, isolation and its impacts on energy opportunities, with nuclear and coal seeming the only realistic options. It reinforced the message that those of us with green-energy leanings in Australia parrot out all the time – there’s so much energy here that we have no real excuse to burn all of this coal.

What energy are you using to access this blog, and what are the alternative pathways from the sun to your screen?energy-transformations1-300x174

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