With global warming and the energy crisis both affecting our planet more than ever before, it is no wonder than solar energy is ever more talked about in the press. Solar power provides us with a fantastic alternative to relying on fossil fuels that are filling our atmosphere with fumes and causing a drastic rise in temperature while at the same time quickly running and leaving us looking elsewhere for our power sources.
Fortunately solar energy is something that will always be available and that will always be readily usable as long as our planet lives (when our sun runs out, so does our time). Commonly we see businesses and homes with solar panels that can drastically reduce their energy costs and we have probably even used solar energy ourselves – in calculators or even to charge our phones. So how does this all work?
Actually there is more than one type of solar energy and its exact methodology is deigned by both the intended use and the type of energy gathered from the sun. Here we will look at two forms of energy conversion, both of which use solar panels of different types. These are ‘solar thermal’ and ‘photovoltaic’.
Solar Thermal: Solar thermal energy is a form of energy that uses the sun’s energy for heat – collecting heat directly from the sun’s rays and then using this to heat buildings and water. These panels are angled to absorb the maximum amount of heat during the day and contains small tubing through which water circulates. These tubes are known as ‘solar thermal collectors’ and in some cases these will be filled with anti-freeze liquids rather than water. Quite simply the water is heated up in small amounts and then taken to where it is needed – as simple as sunning yourself for heat.
Photovoltaic: Photovoltaic solar energy meanwhile is the type of energy we associate with solar power and which can be used to power our electrical devices. It is unfortunately a little more complicated however.
Essentially photovoltaic cells are made from silicon materials that absorb sun light (light rather than energy – hence photovoltaic). Here the solar energy ‘excites’ the electrons in the solar cells causing them to behave as direct current (DC) to be transformed into alternating current (AC) at 120 volt for home use. For larger commercial uses, multiple solar panels can be linked together in order to create more power. The process by which the electrons are excited into behaving as a current is one called ‘electromagnetic radiation’.
These types of solar energy are both known as ‘direct’ forms of solar energy. They are direct because they absorb either heat or light from the sun directly and convert this into heat or electricity to be used in the home. They are different from ‘indirect’ solar energy, which is any energy that comes indirectly from the sun – such as geothermal energy which is energy stored deep within the Earth which has been gradually heated by the sun over long periods of time and insulated by the rock around it.