These days you just can’t miss solar energy. Everyone’s talking about renewable energy more often than not putting solar in the prime spot (though there are other popular technologies like those harvesting wind and water energy). Here we want to talk about the energy of the Sun and tell you what we think everyone should know about it. So without further ado, here’s what we have:
1. Solar energy is abundant
In just one hour the total solar energy absorbed by Earth’s atmosphere, oceans and land masses is enough to power the world for almost a year. In 2002 when our energy demands were slightly lower, that one hour of sunlight could’ve powered the year for more than a year.
2. There are two types of solar technology
Broadly speaking there are passive and active solar technologies depending on the way they capture, convert and distribute solar energy. Active solar includes photovoltaic (PV) panels and solar thermal collectors to harness the energy, while passive solar techniques include orienting a building to the Sun, selecting thermo-friendly materials and designing spaces to naturally circulate air.
3. Solar technology can also be used for other things
Aside from power generation, there are solar technologies (called solar thermal technologies) that are used for water heating, space heating, space cooling and process heat generation.
4. Most popular active solar power technologies use Photovoltaic (PV) or Concentrated Solar Power (CSP)
Photovoltaic cells (PV) convert light into electric current using the photoelectric effect. Some materials can absorb photons of light and release electrons, which are then captured to create an electric current that can be used as electricity.
On the other hand, Concentrating Solar Power (CSP) systems use lenses or mirrors along with tracking systems to focus a large area of sunlight into a small beam. The concentrated heat is then used as a heat source for a conventional power plant. Among the CSP technologies, most used are the parabolic trough, the concentrating linear Fresnel reflector, the Stirling dish and the solar power tower.
5. How to store solar energy?
One of the major problems with solar energy is that it’s only available during the day, prompting scientists to think about the energy storage issues. There are several mechanisms developed to store the new energy, most of which depend on the technology used. If we’re talking about PV-based solar installations, rechargeable batteries have been used in the past. Lately, the excess electricity is returned to the power grid.
Then there are thermal storage systems that rely on readily available materials with high specific heat capacities such as water, earth and stone; as well as phase change materials like paraffin wax and Glauber’s salt.
Finally, certain solar installation used pumped-storage hydroelectricity to store energy in the form of water pumped when energy is available from a lower elevation reservoir to a higher elevation one. Afterwards, the energy is recovered when demand is high by releasing the water to run through a hydroelectric power generator…