Solar panels are heralded as the future of clean energy and alternative energy with the sun delivering several thousand times the energy needed by mankind. Although the sun gives away this huge amount of energy seamlessly across the globe, harnessing that energy and converting solar energy into electrical energy that we can use for multiple purposes remains a major challenge. Solar panels address this barrier to some extent even as researchers are relentlessly engaged in finding ways to make solar panels and the energy derived through the panels far more affordable.
ACT Greens MLA Shane Rattenbury, Planning Minister Mick Gentleman and Daniel Radford lifting panels at the Williamsdale solar farm. Photo: Ricky Fuller
Photovoltaic is the term used for the process of converting solar energy from the sun into electrical energy. Solar panels consist of several cells held together to allow light particles or photons to disintegrate electrons from the atoms and generating electricity in the process. When you examine the photovoltaic cell, you can notice that each cell appears like a sandwich comprised of 2 slices of semiconductor material, generally silicon that also finds application in microelectronics.
Photovoltaic cells in the solar panels should create an electric field that is more like the magnetic field resulting from opposite poles. Separation of opposite charges gives rise to an electric field. Solar panel manufacturers ‘dope’ the silicon with an array of other materials so that every slice in the sandwich has a negative or positive electrical charge. More specifically, the top layer of the silicon is seeded with phosphorous to add extra electrons with negative charge to the particular layer. Meantime, the other layer in the sandwich is treated with boron to create the positive charge through fewer electrons. Through this process, an electrical field is generated at the intersection between the two layers of silicon. Subsequently, when sunlight sets one electron free, that electron gets pushed out of the silicon intersection due to the electric field.
Other components within the cell turn the electrons into electrical energy that we can use. Conductive metal plates placed on the side of the cells collect these electrons to transfer them to the wires. At this point, the electrons are capable of flowing just like other sources of electrical energy.
Solar power technology other than PV cells
Solar power technology is not limited to the photovoltaic cells and includes CSP or concentrated solar power and solar thermal that work differently compared to the solar panels. However, the underlying purpose is to harness energy from sunlight to generate electricity or heat used in varying applications.
Some of the earliest application of solar energy included calculators and wrist watches. These devices had no batteries or even buttons in some instances. Only a light source was needed to energize these devices and that light source could even be from your domestic lights. Solar panels have also been immensely useful in call boxes, parking lots, and emergency signs on roads. However, space science was among the pioneers to adopt photovoltaic in power electrical systems of satellites.
Some day we may have free power from the Sun
The prospect of free solar energy from the sun is indeed a seductive promise because the sun gives out as much as 1,000 watts energy for every square meter that he purveys on the surface of our planet. A day might dawn, sooner than later when we harness at least a part, if not all that energy to power up our offices and homes for free. For long, fossil fuels have performed this function with some assistance from nuclear and hydro electrical sources.
The severe impact of carbon emissions from fossil fuels is already known to most of us. Plenty of action has been initiated by global leaders to contain carbon emission and limit or reverse its effect on climate change. One of these measures is an enhanced focus on clean energy. While solar energy is a major source of clean energy, the other contributors are wind energy and geothermal energy.
Solar panels getting cheaper by the day
In the last 3 decades, the cost of solar panels has come down from a high of $100 per watt to as low as $0.60 per watt. Companies like eurosolargroup who are a part of consortium like eurosolar are doing their bit.Researchers around the world are relentlessly engaged in finding more affordable and convenient means of harnessing this huge source of energy. Nevertheless, solar energy using photovoltaic cells has been making great strides in many nations including Australia, the United States of America, China, and Japan. Germany merits a special mention here since she is the first to meet the nation’s total energy needs through renewable energy sources.
Storing solar energy
Storing electrical energy produced from solar energy is another bottleneck in the progress of the solar panel industry Thankfully, Tesla Motors of the U.S.A., has embarked on an ambitious plan to address this. The Powerwalls introduced by Tesla Motors has been very well received by the markets. When consumers have the ability to store solar energy and possibly even feed their excess energy to the grid, the overall cost of energy to the consumer is expected to drop further making solar energy even more cost effective in the long run.
U.S.A. today has more manufacturing capacity than the domestic demand. But, apart from the cost of solar panels, another stumbling block in the progress of this clean energy source is the ability to store the energy garnered during the day and put it to use during the night. Batteries than can store solar energy, such as the one being offered by Tesla motors could be the answer. Making such storage more affordable will be a giant leap towards making clean energy viable for mass consumption. Given the global thrust on reducing carbon emission and working towards clean energy, more players could be picking up the queue from Tesla motors even as researchers continue to find more economical means of producing such batteries. Gradually, more and more utility companies will also start shedding their inhibitions and learn how solar energy can shore up their bottom line. The near absence of transmission losses alone ought to work in favour of solar energy for the utility companies.
Keep glued to all the developments in solar energy in your local area and soon you could be making significant savings on your electricity bills.