The word ‘solar’ has taken on a lot of new meanings and implications in recent times, especially in Kerala. But in most other parts of the world, it is still more popular as an economical, viable and non-polluting alternative to traditional sources of energy. Let me explore a bit into the latter, lest the scientific aspects of it should be drowned in the political swamp.
At its simplest, solar energy is the heat and light we get from the Sun. Technology has made it possible to harness this energy in so many ways, so we can make use of it in an efficient manner, and convert it to whatever form we need it to be in. That means, even if it isn’t heat and light you need, the heat and light from the Sun can be used to generate whatever form of energy you need. The first solar cell was demonstrated in the late 1800s, while Albert Einstein won the Nobel Prize in 1921 for explaining the Photoelectric Effect. I will not go into the complex science behind it, but essentially, this meant that solar power could now be used to generate small amounts of electricity.
I first saw solar power being used on a solar calculator, when I was around ten years old. Unlike a battery powered calculator, this one needed significant light to work, ideally by placing it near a window. Then I came across a solar lantern, which was supplied by the Agency for Non-conventional Energy and Rural Technology (ANERT). The lantern came with a solar panel, which was roughly 2 ft X 2 ft in area, and about 2 inches thick. Once charged through the day, the lantern’s small fluorescent lamp would work for about 4 hours, which was considerably better than the hour or two which rechargeable battery powered emergency lamps of those days were capable of.
Then, solar water heaters made an appearance. These were (and still are), large panels with water running through them in tubes, getting heated naturally through heat from the sunlight falling on these panels. It was a clever piece of engineering that served the purpose without too many complicated components. There was no electricity involved in any stage. Once installed, operation was free (since it depended on the sun) and did not drive up your electricity bills. These heaters were of course bulky and needed significant space on a terrace (or high other area exposed to sunlight) for effective operation.
At least in the initial stages, that was always a drawback of solar energy - the sheer size of the panels required to draw meaningful amounts of energy made it non-viable. The amount of electricity produced was directly proportional to the area exposed to the sunlight. In fact, one of the earliest references of solar energy I came across (about 20 years ago in a science book for children) said that 20,000 wafers of silicon are required to generate 0.5 V of electricity. The normal AA (pen-torch) battery gives you 1.5 V, if you want to compare. Of course, there are other numbers too to be considered when describing a source of electricity, but let’s keep it simple here. In short, to generate a lot of electricity, you need a lot of free area on which to place solar panels.
Theoretically, it is estimated that India should be able to produce about 5000 Petawatt per year (that is 5000 trillion kWh, or 5000 trillion “units” as the Kerala State Electricity Board would call it) based on the amount of sunlight that reaches the land alone. But then, we can’t cover our entire land with solar panels, can we? So we need large areas of free land. Large expanses of deserts are a good option for this, especially since the lack of trees ensure long periods of unobstructed sunlight. This is why Gujarat and Rajasthan (especially the Thar desert) figures prominently on the solar energy map of India, along with Tamil Nadu and much of Central India. Land being a scarce resource in Kerala, we will need some other means to set up large scale solar units in our state. Of late, there have been solar panels set up on the roofs of railway stations and other public buildings, which is a good way to make the most of whatever space is available.
So why don’t we put up solar panels across the large tracts of unused land in the countryside? There are a few problems with that logic. First of all, the infrastructure needed for solar energy (the panels, etc) is expensive. Although they don’t need much maintenance in the traditional sense, it is important to keep the panels clean, so that the sunlight can reach the parts that matter. Imagine the effort required to brush the dust off such huge panels on a regular basis! Also, while the power generation process itself is not polluting, the construction and installation of solar panels of such size obviously requires factories that involve a lot of the conventional evils like polluting fuels, chemical wastes, etc. And the most important aspect to be considered is the longevity of the solar power generation system. Once in every 25-30 years, the entire panel system (or most of it, at least), needs to be replaced. After that period, the massive panels have to be disposed off or recycled effectively. That too costs money.
Another problem that is probably unique to Kerala is something that cropped up quite recently. After the much publicised scam, will any company really dare to approach customers with solar power projects? If they do, will customers dare to accept them as genuine and invest in them? Let’s hope that a few irresponsible (or illegitimate) companies don’t give the genuine ones a bad name.
Once these problems are taken care of, solar power is actually a fantastic source of energy. Think of it this way. There is this giant battery in the sky, and all we need to solve all our energy needs is a means to plug into it. Once we figure that out, all the solar powered cars (which are already in existence) and the solar powered houses and townships (rare, but yes they exist) can come into the mainstream and be the rule rather than the exception!
