Tuesday, May 6, 2008

Does the Sun Power Everything?

Touted as the cleanest and only cost-free energy source, finding ways of getting our energy needs from the Sun can no longer be ignored. But is it stretching the truth a bit when we say that the sun powers everything around us?

By: Vanessa Uy

Currently it seems like every one is involved in the race to harness the energy that streams down on us from the Sun. Touted as the cleanest renewable energy which sends us light with no monetary costs whatsoever. It seems like harnessing the Sun’s radiant energy is the best thing for us since free money, but shouldn't we know more about our nearest star first before putting all of our energy security eggs in one solar basket?

Some might harbor the notion that the sun is renewable, actually it’s not. The Sun has been slowly dying for 5 billion years. And 5 billion years into the future, it will turn into a red giant star that would kill all forms of life on the Earth’s surface. But given the vast time scales – and we humans have only been around for less than a million years – it’s safe to say that the sun could be considered “renewable”. Who knows that a few centuries from now we could develop technologies that allow us to travel and colonize other Earth-like planets in other star systems, with the same ease as flying to a vacation spot 1,000 miles away like we currently do. Remember folks, our manned space program is there for humanity’s long-term survival. Our civilization could potentially outlive our Sun.
The ancient plants used the Sun’s radiant energy as they grow then later died hundreds of millions of years ago. Their (the plants and the ecosystem supported by it) long dead bodies are where our crude oil and coal comes from, hence the term fossil fuel. A mighty testament on how solar energy is stored and sequestered naturally, and these fossil fuels are still full of that solar energy made by the Sun countless of eons ago. The bad news is we are using it faster that nature can replenish back the supply. So we should find ways to extract power from the Sun directly.

Wind turbines, hydroelectric power, even wave power’s apparent renewable credentials are nothing more than the Sun powering our planetary weather and climactic system. Blowing air around that allows wind turbines to generate electricity. Our Sun heats up the water on the ocean’s surface evaporating it. Then sending water back to the mountains as rain that flows back to the rivers, whose flow is harnessed by hydroelectric plants before the water flows back to the sea, thus the cycle repeats again. Even the waves and sea currents that we are now learning to harness are ultimately powered by the Sun.
The radioactive elements we used to power our nuclear fission power plants can be traced back our Sun’s precursor which is several times its size. Given our current knowledge of Astrophysics, our Sun’s large precursor did not die quietly. It exploded into a supernova which during the several billionths of a second before blowing itself to bits, created of most of our planet’s supply of uranium. And because of this explosion, our Sun was eventually born. Even geothermal power owes its existence to the nuclear alchemy of a supernova explosion because our planet’s internal heat is nothing more than a natural nuclear fission reactor.

Given our current understanding of the Sun’s benefit to us – from the very distant past to the farthest recesses of our distant future – only leaves us with awe. And our current fascination in harnessing this cleanest source of energy that’s relatively free will only increase in quantity and sophistication as time goes on. The pre-Columbian civilizations of the Americas were really on to something when they decided to pay homage to and worship the Sun. The Sun really did make everything possible.

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