Solar power is a new concept and there will always be apprehensions before adopting it. However, if you can understand the basics of how does solar power work, you’ll make an educated decision on which solution works to solar power your house. The building block of solar energy is the photo voltaic cell or PV. There has been a lot of research and development around PV over the last ten odd years, primarily due to a push from the government. Today you have many products in the market and picking one can be really tough. This is where understanding about solar energy is useful.
The first thing to understand about solar energy is its source which of course is the sun. The sun is a nuclear reactor with reactions releasing energy every second. This energy is released as heat and light, the important concept for solar power is the light. Light is released as photons that travel like waves. These waves have what is known as a wavelength which is basically the physical distance between two photon particles in the same state of motion. Another aspect that is related to wavelength is the frequency.
Why are we talking about wavelengths for solar power? Well because the wavelength at which the solar equipment works is vital to judge how effective it would be. The sun’s light consists of many color frequencies. We can see some and we can’t see the others. Incidentally, the sun’s radiation contain more infra-red radiation than the visible light ones. So solar equipment that works under infra-red light absorbs more energy. Another concept is the light absorption. Anything that seems to have a color actually absorbs light from all other color wavelengths except its color – which it reflects back and hence we see it. Anything that looks black absorbs all the light, hence black solar equipment works better than colored ones.
Here is some mind boggling statistics for you – the total radiation from the sun that falls on the earth every day is 35000 times more than what we need for all our use. Imagine the gross waste of this abundant and clean energy source. In fact, if we can tap 6 kWh of sunlight from a 5 sq. meter area per day, we can power a house for that day. So the catch here is to capture maximum sunlight. The interaction between the photovoltaic cell components and the sunlight is vital in achieving this. There is an an interesting article on the site EzineArticles about portable solar power. Go there for more info.
An important concept in the construction of solar equipment is the idea of passing light. We looked at material that absorbs light and the ones that reflect some of it. There are some other materials that actually just let some colors pass through them – like the glass which allows white light to pass through. These materials not only let light pass though, but they also block the heat, thereby protecting the solar equipment. These materials are great for what’s called glazing on solar devices. The glazing material has a property called filtering. Not all materials allow white light to pass through them. Some of them absorb or reflect some frequencies and allow some to pass through; this is the filtering property of the material. The glazing materials used in solar equipment need to pass infra-red light and filter out the rest.
So there are three characteristics of any material: filtering, absorbing and reflecting. Even the windows made from glass that are supposed to pass white light do not do so completely; they actually pass just 85% of the light and rest is lost or filtered. Another common filter is our atmosphere. During dawn and dusk the sun’s rays travel further in the atmosphere and hence they are not that strong or bright. At noon, with sun directly overhead, the light travels perpendicular to the atmosphere so it traverses shorter distances this means it gets filtered less and hence is more powerful.
The same logic holds true for summer and winter months too. Due to the position of the sun and earth a lesser amount of sunlight makes it to the earth surface during winters as compared to summers. As a result, less light can be absorbed during winter. Since absorption of photons releases heat during winter months less heat is released as compared to summer months. These are some concepts you must know to understand how solar energy works.
Want to find out more solar power facts then visit Richie Vee’s site on how to choose the best solar power kits for your needs.
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