Energy is nice. Real nice. I mean, when you walk in to a bustling building, you are immediately surrounded by all sorts of energy: heat energy, electric energy, kinetic and potential energy. It is literally everywhere. Well, where does all this energy come from? Food, the electrical outlet, gasoline – all correct answers, but what about before it is in those forms? Where do those stores of energy originate from? It may be a longer story then you expect.
Food is potentially the easiest to figure out. Let’s start at the sun. Energy is released from nuclear reactions in the suns core, some of which is then emitted outwards into space in the form of solar radiation. After a quick 150 million kilometer journey taking some 8 minutes, some of that radiation smashes into a nice small blue planet, earth. Ignoring electromagnetic forces causing some energy to be shed before reaching the atmosphere, we then get our first dose of energy as some of the solar radiation interacts with our atmosphere, warming our little bubble which surrounds our wet rocky abode. Oh, doesn’t it feel good? If only the atmosphere could catch a little more of the energy! The bits of energy from the sun that are able to slide through the atmosphere mosey on for a bit until they hit whatever it is in front of them. Maybe it is a asphalt parking lot, maybe it is your hair, or maybe it is a leaf. Unlike when the radiation hits asphalt or your hair, when the energy hits the leaf, some of it is converted into a new form of energy, chemical energy, by the process of photosynthesis. CO2 from the atmosphere is converted into longer carbon chains. Yep, we all learned about it, starting back in grade school. Still, it is actually a processes far from simple; despite great interests and investments, scientists have still not been able to successfully replicate photosynthesis in human made devices. It is truly a miraculous process. Anyways, not all of the energy that hits the leaf is stored. Some turns into diffuse heat and some helps the leaf and plant to grow. Eventually, some hulking tractor dragging a shockingly complex plant harvester comes along and removes the plant – and the energy it holds – from the ground. That plant, or leaf, or fruit on the plant can then be food for us secondary consumers. While we all may enjoy the sunlight and even take in a few beneficial vitamins from its rays, we can not turn its energy into a form useful to our muscles. Instead, we ingest the stored chemical energy from plants (or some less efficiently produced derivative of the plants – yes, meat) and use it to power our every move and thought.
So that is nice of the sun, to indirectly share its energy with us in the form of food. But what about other forms of energy we use? What about the electricity that runs my computer, the gasoline that powers my car, the steam that runs turbines in power plants? Where do we find these things? Electricity wells right? Never ending ones I hope. Sorry to patronize you, but sometimes it is worth thinking this through. Nearly all sources of energy, electric or other, also come from the sun, albeit through an extended path. Let’s start where we were above, just before the big John Deere arrived on the scene. Let’s also pretend our little plant friend isn’t around today, at least in the typical sense, but existed about half a billion years ago, well before humans even walked the earth. Imagine this plant is surrounded by many many other plants, maybe in a hyper-productive marsh type environment. Collectively, all the plants are just hanging out in the sun, soaking in some rays. This is their life. Maybe some will have little baby plants, who knows. Some will surely be eaten by little critters. The majority, however, just reproduce, live their life, and then die and go to plant heaven, leaving their earthly vesicles behind, deteriorating among their friends and family. Well, the energy that these plants store is not suddenly released when they die. In fact, if they are not eaten or decomposed by bacteria, their stored chemical energy can hang around for a quite a while. Over time, lots of lots of time, organic debris from plants, algae, whatever, accumulates. Sometimes, large deposits of accumulated organic matter is then buried either by tectonic processes or sea level rise. Those poor plants, all that hard work and they are just buried! Maybe you know the rest – those pockets of concentrated chemical energy are then sometimes pushed far underground and compressed and subjected to heat. The end result: highly concentrated energy bubbles. Remember, these highly concentrated energy bubbles are the culmination of many years of storing the relatively diffuse sunlight that hits our planet in a process that we still can’t mimic. Some of the pockets are converted into natural gas, some into oil, and some into coal. They hang out deep beneath the surface for anywhere from 1 to 500 million years or so.
Then, out of nowhere, BOOM! A drill head pops through the overlaying impermeable rock. Freedom! A pipe is conveniently attached that allows the precious concentrated energy, the naturally altered remains of millions of plants, to flow or be pumped up to the surface again. Thank goodness, must be boring down there. In this example, let’s say we pumped up oil. It is then transported to a refinery (which ironically runs on refined oil – which came first? the refined oils or oil refinery?) where it is altered into a form more useful for our combustion engines. Finally, it gets shipped out in a truck, delivered to a gas station, pumped into your car, and exploded in your engine, releasing the broken down products of the chemical energy stored in carbon changes. One major product: CO2. We’ve done it, come full circle. We have finally released that poor CO2 those pesky plants stole millions of years ago. Lucky for the atmosphere (or not really since it doesn’t care), CO2 helps “catch” sun rays and warm the atmosphere (climate change). More on this and many other problems later…
Excluding nuclear reactors (not to ignore some major problems associated with nuclear reactors, least of all being meltdowns which render entire areas of our planet uninhabitable), every other power source we have runs by releasing the concentrated energy stores by plants over millions of years and converting it into new forms we have grown to enjoy – electricity, heat, anti-heat (air conditioning), kinetic energy, whatever. Isn’t it great?! Those silly plants did all that hard work and now we are reaping all these great benefits! Just 1 problem… or maybe 2. Or 3. Or 10. Well, there are a few problems, but first, lets think a little more about how we use them in (2) The Sinks