When looking for ways to reduce our carbon footprint, to preserve our natural resources, and to use more sustainable forms of energy, there is a range of different renewable power sources available to us. These include things like solar power, geothermal power, wind power and tidal power each of which has their own advantages and disadvantages. What many people don’t realize though, is that in many ways, ALL these forms of energy come from the sun initially and even when you use wind turbines instead of solar panels, it’s still the sun you can thank for that power. Confused? Read on and I’ll explain…
How All Renewable Power is Solar
The point is that while you might not harness energy directly from the sun in every instance, indirectly it will almost always have come from there. Below is an account of how this is the case in each instance…
When you use a wind turbine you are of course harnessing the power of the wind and the kinetic energy that generates, but indirectly that power actually comes from the sun. This is because wind is caused by variations in the air pressure at high and low levels which forces gusts of air to ‘rush’ in and fill the pockets where the pressure is low. Those pockets are caused due to the rising of some air particles in relation to others, which in turn is a result of the air being heated up by the ground and the sun. In short, the sun heats the ground, the ground heats the air, the air rises and so low pressure underneath causes a gust of wind for you to harness.
Geothermal energy is even easier to link back to the sun. Geothermal energy effectively works by running pipes deep under the ground filled with water which are heated up by the surrounding soil (which is very hot at this level). That soil is only hot though because the Earth has been baking in the sun for so many thousands of years and the stuff under the surface hasn’t been cooled by wind and water. You may be getting energy from the ground, but the ground is only hot thanks to the sun.
So how is tidal power linked to the sun? Well this link is a little more tenuous as actually the motion of the waves is caused by gravity from the moon, but the sun is still in there. For one, the wind does also contribute to the movement of the sea, but more importantly the moon and the Earth are only in the positions they’re in to begin with thanks to the gravitational pull of the sun. The moon was no doubt created when the Earth was hit by an asteroid, and the only reason that our planet ever came close to an asteroid belt was because both were held in place by the sun. In short all the chaos that the sun brings us is actually necessary for life to thrive.
Biofuel is energy that comes from organic matter such as plants and straw. We burn these to release the energy trapped inside, but of course that energy is also created by the sun. The trees synthesize sugars through a process called photosynthesis which relies on the sun, and this energy is then passed through the food chain via a complex myriad of life forms. Whenever you eat something you are essentially stealing the energy that it stole from another organism that originally came from the trees and the sun (and carbon dioxide). In fact it’s only through fusion that the heavier elements are formed, so we can thank ‘suns’ in plural for there being any carbon in the universe to begin with.
Interestingly scientists may be close to being able to mimic the process of photosynthesis. Recently a researcher named Daniel G. Nocera managed to create an ‘artificial leaf’ that works like a normal leaf but produces hydrogen rather than oxygen to be captured by fuel cells. A new form of solar power?
Even the environmentally unfriendly forms of energy come from the sun initially. When you burn coal what you’re actually burning is carbon that has been compressed over thousands of years but which still contains the same energy. Coal was once organic matter and the energy it contains came indirectly from the sun.
So what does this tell us? Well for one it’s a fascinating way to think about energy, that demonstrates just how it can be transformed and recycled in many different ways by life and the forces of nature. At the same time though it tells us that the sun really is the origin of energy and so the most potent form of energy. Surely that’s where we should be looking to power our lives?
This post was contributed by Gemma Hastings; she likes to write on topics she feels strongly about including the use of solar and clean energy in daily life. She works for a company that helps install solar panels that are most suited to the client. You can find out more about them through their website.