About Solar Energy & How It’s Harnessed

If you want to be really pedantic and scientific when you talk about solar energy, you could say that technically all forms of energy used by humans is ultimately solar energy.  Energy derived from wind and water rely on the weather cycle – which is stimulated into circulation by the heat and energy of the sun’s rays striking the planet’s surface and atmosphere.  Energy derived from plants (by eating food or by burning wood, or even by harnessing methane gas from an anaerobic digester) originally got into the plants by photosynthesis using the energy of the sun.  The same applies to fossil fuels, as these were originally plants, which got their energy from the sun.  The only form of energy used today that isn’t solar energy is geothermal and nuclear energy, and you could even argue that this is closely related to solar energy.

But when most people talk about solar energy, they usually are talking about energy used either directly for heating, lighting and the like, or about generating electricity using solar energy using photovoltaic panels.

Passive Solar Energy

If your home has any windows at all, you probably know something about the potential for the heat of the sun’s rays to light your home (or office) and to keep it warm.  Just look at how animals behave – cats always seek out the sunniest spots to sleep in, soaking up the rays of the sun.  As people look for more ways to stop relying on fossil fuels and extravagant use of resources (or electricity), home designs are taking more though about solar energy, particularly passive solar design to heat homes.  Newly built houses are often oriented to the sun rather than to the street – even if this means the main living area is at the far side from the street.

Solar Water Heating

Solar energy is also being more widely used for domestic water heating.  The good thing about this form of solar energy is that it can be retrofitted to an existing house, unlike passive solar design, which needs to be incorporated into the house from the beginning.  The good thing about solar energy used in this way is that it can dramatically cut household expenditure on electricity – heating water is one of the biggest consumers of domestic electricity.

Solar Panels and Photovoltaic Panels

Some people think about solar energy as a way to stop paying money to mainstream electricity providers altogether.  Living off the grid and relying on solar energy usually involves using photovoltaic panels (also called PV panels or solar panels) to generate their electricity needs.  Some homes also incorporate other solar energy features in them, such as passive solar heating and solar water heaters.  Some even go further and use solar ovens for cooking or use solar incinerators for getting rid of toilet waste.

Concentrated Solar Energy

As energy prices rise across the globe, energy providers are seeking ways to make better use of the sun through a relatively new technology called concentrated solar power. This requires a ground based system to concentrate many square meters of solar energy and focus it on heating water and spinning a turbine. More about this technology can be found at this site., you can also see an example of a concentrated solar power plant in the image to the left. Google sees this as a great source of renewable energy and it has therefore invested in a company that 

Solar Energy on Earth and In Space

Despite the incredible amount of energy which the sun delivers, it can only provide so much. In fact, a large majority of the energy from the sun never reaches the earth’s surface and much is dissipate into space. This is why sattelites depend so uch on using solar power – without any atmosphere, cloud cover or other airborne particles blocking the sunlight, they can absorb a lot more energy from the sun. This has even drawn the attention of innovators who believe it may be possible to build sattelites that orbit the planet and harvest solar energy back to the planet.