Tech Speak: Rarified Earth Vs. Solar Energy: How India’s Power Solution May Cause Big Problems
There’s been some interesting news out of India this week. India’s newly elected Prime Minister Narenda Modi has announced his intention to use solar power to bring electricity to the more than 400 million people in his country who had previously been living without. Now I don’t know about you dear reader, but my relationship with international news is very much like my relationship with the sun. Being the somewhat seasonally affective person I am, I can’t actually say that I don’t ‘like’ the sun; but I tend to have ambivalent feelings towards it when it isn’t benefiting me directly in the same way that I also tend to loathe it when it hangs around for too long. Which is, I might add, quite a silly position to maintain when, on a cosmological scale, the sun is just about the most important thing in our solar system (the big man at the centre if you will). And since the sun isn’t a particularly stable —nor well meaning— ball of superheated gas, making a habit of ignoring it could prove rather fatal. As if it were to: a.) launch a particularly strong and unexpected burst of superheated radioactive flatulence our way; or b.) violently explode; or c.) simply go out; we probably wouldn’t survive long enough to become philosophical about the outcome.
Now don’t get me wrong, I’m not trying to imply that India is by any means responsible for the surly disposition of our sun. Or that by trying to harness the touchy light emitting gas-bags rays, that the nation is doing something wrong (As the humanitarian benefits of large scale solar power domestications are laudable in the extreme). Instead what I would argue is that in terms of magnitude, the solar power harnessing energy proposal being put forward by the Prime Minister at the moment is worth taking note of. Because dear friends when India’s Prime Minister speaks… “The World” (or at least as much of the world that likes to enjoy the wonders of rare-earth metal inspired modern technology: vis-à-vis cellphones, computers and other assorted electronica) aught to pay attention. Lest we find ourselves blind sided by a dizzying confluence of technological innovation, green power, and the problems caused by a commodities trade in desperate need of a recycling program.
What is Solar Power and how does it work?
Our ability to harness the sun’s rays via the use of Solar Power technology and the Solar Power Cells which enable us to do so has a long and storied history going all the way back to 1839 when a man named Alexandre Edmond Becquerel first observed the “Photovoltaic Effect” (that is transforming solar rays into an electrical output) when he connected an electrode to a conductive solution made out of an acid base mixed with silver chloride. Since 1839 the technology through which we obtain and store our solar power has become a great deal more sophisticated, but the underlying Photovoltaic Process remains very much the same. Sunlight hits an array of solar cells set up by scientists or your local power company, and the energy produced by the Sun’s electromagnetic radiation adds to and excites the electrons in the semi-conductive material (usually some form of rare earth metal) which given enough stimulus, then produces an electrical current which can be captured by attaching the cell to a circuit attached to a battery by a processed referred to as “Photoconductivity.”
The semi-conductor (and the material that its made of) ultimately ends up being the most important part of the process. As the more efficient a particular semi-conductor is at transforming solar radiation into electrical energy, means that less potential energy is lost during the photoconductive conversion process. This is why the overall effectiveness of a solar panel at capturing the energy which is being directed at it is expressed as a percentage.
What might come as a surprise to some readers (and if you want to see a more in depth breakdown of the numbers please click here) is that in terms of overall efficiency solar power cells have taken a very long time to come up to par with the energy conversion/capture percentages of other forms of electrical power generation. Dirty forms of power conversion/capture like coal burning can have an efficiency rating anywhere between 32 and 48% depending on the type of burning methods being used. Natural Gas power plants can run anywhere between 32 and 60% depending on what kinds of technological apparatus’s are being used to augment them. Whereas “clean forms” like hydro electric generators and wind turbines, have efficiency ratings which run between 85 to 90% and 30 to 45% respectively.
Solar Power, on the other hand, has only recently reached the 44.4% efficiency mark this past year with the help of Sharp’s cutting edge Concentrator Triple-Junction Compound Solar Cell. A piece of solar capture technology which means of photoconductive solar conversion is about as complex as the name sounds. As the CTJCSC makes use of three layers of semi-conductive materials in addition to a specially designed magnifying lens to increase the amount sunlight being captured by the cell. Which is unfortunate, because when compared to the average consumer solar cell (that tend to clock in at a somewhat disappointing ± 20% to 25% efficiency capture/conversion rating), building one of these things is extremely expensive.
What Problems Does Solar Power Face?
The problem with using Solar Power as a means to generate and capture large amounts of electrical energy is that it (like wind power) has many inherent drawbacks. The first is that on a day to day basis you need the solar panels to receive consistent and long periods of fairly direct sunlight in order for them to sustain your everyday power needs. You also need to be able to produce enough excess electricity to be able to store it for use at a later time. Otherwise once the sun goes down, so does the power.
Second, the relationship between the number of panels you need to provide enough power for a home…, vs. the number you need to power many homes… doesn’t scale on a one for one basis. For instance the Andasol Power Station in Spain, clocks in at approximately 1.5 million meters squared, and when operating at peak capacity it can provide power for up to 200 000 homes. Which translates into something of a nightmare when you consider that the Indian Prime Minister wants to use Solar Power to provide electricity to 400 000 000 million (Which in turn, works out to India having to build approximately 2000 Andasol 1’s. Which in turn works out to them around 30 million square meters of space. Which in a in country as densely populated as India that’s total land mass is only 3 287 263 kilometres squared, or 3 287 263 000 meters sq. Is actually quite a substantial chunk of land to set aside to provide power to less than a 5th of the population.)
Third, and this is the real kicker, the Rare-Earth Metals needed to create high efficiency panels are exceedingly… rare. So rare in fact that tellurium, the rare-earth semiconductor most frequently used in the construction of Solar Panels —is three times rarer than gold. Ironically, the scarcity of rare-earths isn’t as big a problem as the world’s laissez faire attitude towards recovering them from the items they’ve been used to create. According to one 2009 study, it was estimated that we recover less than 1% of the rare-earth metals contained within our discarded e-waste each year. And since the demand for increasingly advanced mobile technology continues to grow, we could very well face a rare-earth shortage if we don’t start managing and recovering our rare-earth resources in a more effective manner.
So what does this mean for India?
As much as I would like to see Prime Minister Modi succeed in keeping his promise to help these people, doing it through Solar Power alone might prove financially impractical. Because if we break things down to the level of dollars and cents, than the average cost of per kilowatt hour of Solar Power quickly becomes unaffordable for the majority of people living in these impoverished regions.
In his article “Nuclear versus solar,” Power Engineering blogger Denver Nicks takes a look at the price differential between the amount of power being produced by a Finnish nuclear power plant and that of its nearest solar competitor. What he found was that over a 20 year span a 15 billion dollar nuclear power plan will generate approximately 225 terawatt-hours of electricity at an average cost of 7 cents per kilowatt hour. Whereas the construction and maintenance of all of Germany’s current Solar Power Plants (which will produce approximately 400 terrawatt-hours of electricity over the next 20 years) will cost taxpayers 130 billon dollars and work out to around 32 cents per every kilowatt hour. Which means that the power produced by its solar stations will cost Germany around 4.53 times the amount as the power being produced by Finland’s latest nuclear facility.
Given that more than one quarter of India’s population lives below the government established poverty threshold of earning 40 cents a day; electricity that costs close to 32 cents per kilowatt hour in Germany might be considered a bit steep in the poorer regions of India considering that the equivalent cost in Indian Rupee’s is around $25.50. And if that isn’t enough to make you want to beat your head against the proverbial pavement, then the fact that India on the whole is probably one of the most ideal places for Solar Power to be put to use (clocking in at around 2589.77 hours of sunlight per year with some regions being in excess of 3000) is downright tragic.
Tech Forward: Solar Power’s Hexagonal Future
Yet new advances in the field of solar panel design might be able to help overcome the geographic problems which have been inherent to the construction of large scale solar power stations. American inventors Scott and Julie Bursaw have come up with a hexagonal solar panel that is capable of withstanding up to 250 000 pounds of force. Thus making it possible to use the tiles as a replacement for asphalt on roadways and in parking lots. The novelty of this invention is that we can now build solar power into our infrastructure, which in theory, would allow us to turn our cities into small scale solar electric power plants without having to demolish any buildings. And in a country where space is at a premium, this new riff on an old piece of technology might prove to be a more pragmatic solution to India’s power problems than constructing a number of cost inefficient solar power plants.
So unto the sun I say:
“Take that gas-bag! We’ll harness your power yet!”