So I've jumped on the online education bandwagon and started taking Delft University Online's "Introduction to Solar Energy". If you ever thought that you were "good" at the physical sciences, but then spent a decade plus in the wilderness, then taking a course like this will likely be a shock to your system and will probably knock your understanding of the world. That was my experience anyway; but whatever, it's pretty cool because you really need nothing more than some basic integral calculus to do it.
One of the questions posed online provided the table below, stating area of landmass, solar irradiaiton which the country receives (see definition of "sun hours" below) and energy consumption for a set of five countries chosen seemingly arbitrarily.
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| Source: edX course on Solar Energy run by Delft University and taught by Arno Smets. |
So my first act as a student was to look up what a "sun hour" actually is: turns out there is such a measure, and that it's equivalent to 1 kWh per meter2; in SI units, 3.6 million Joules per meter 2 . My homework assignment--for which the answers are fairly straightforward and completely unsurprising--was to figure out which country needed to cover the greatest proportion of its landmass to photovoltaic cells if it wanted to satisfy all of its electricity needs from solar energy alone. Note that, to answer the question, you can ignore caveats to do with the efficiency of photovoltaics (which seem to always be 15% in the textbooks) or what the conversion factor is for solar irradiation to electricity, or even the conversion from DC to AC. In the shower this morning, the question that came to my mind between shampoo and conditioner was: how does Qatar rank on these scores?
One (advertorial?) source places the amount which Qatar receives as 1,858 kWh per year as an average, making the daily rate not much more than India's (surprised? I was), and twice that of Britain's (really thought it would be more ...). Of course, Qatar also has a tiny surface area: not much more than about 11,000 km2 (or so I estimated).
As you would expect, Qatar's electricity consumption jumped in tandem with its population in the years from 2006 to 2012; at 18.79 billion kWh (source: Index Mundi). When you plug the numbers in, it's also clear that on the count of "energy consumption per unit of area" (something I kind of made up, I think), Qatar tops all of these countries:
| Country | Energy Consumption per Unit Area |
| United States | 14,237 |
| India | 10,503 |
| Brazil | 1,926 |
| Spain | 19,031 |
| UK | 50,938 |
| Qatar | 61,494 |
...and by a mile. FWIW: Qatar, while receiving twice as much solar energy per unit area in comparison to the UK, would need, proportionately, six times as much of its landmass as India converted to photovoltaic cells to satisfy all of its electricity needs from solar energy.
Just like with the hamour fish, we're consuming far, far too much electricity.
