|Solar panel efficiency is a measurement of how much solar energy in a panel can be converted into usable electricity. / Photo by zstock via Shutterstock|
New solar technology has set a world record for reaching 47% efficiency in the lab and 39.2% in one-sun real-life illumination. Solar panel efficiency is a measurement of how much solar energy in a panel can be converted into usable electricity.
Solar panel with the highest solar conversion efficiency
A team of scientists from the National Renewable Energy Laboratory (NREL) in Golden Colorado, United States has fabricated the six-junction solar cell that now holds a world record for having the highest solar conversion efficiency. Before their work, the highest efficiency solar panels on the market can reach only 22.8% efficiency and the average efficiency of solar panels drop between 17% to 19% efficiency range.
To fully appreciate what the big deal is in this discovery, there’s a need to understand the jargon used by the researchers. First, scientists determine the solar efficiency by knowing the electrical current that is generated once the sunlight interacts with the photovoltaic cells in the panels
Since 2010, solar panels have only been increasing in efficiency at about .5% every year, according to solar marketplace Solar.com. Three major components affect the solar panel efficiency equation: the panel material components, thermodynamic efficiency, and reflectance efficiency.
Another aspect to understand in the study is the multijunction cell. It is a solar collector cell that utilizes more than just one layer or “junction” of solar technology. Since the sun emits electromagnetic radiation at many wavelengths, different receivers are also needed to capture the wavelengths of light.
Individual solar may have an efficiency of just 17%, which means that 83% of sunlight will be reflected on another surface. However, by stacking solar technology from six solar cells, the NREL scientists have increased the solar panel’s efficiency multiple times. The new solar technology developed shows an “extraordinary potential of multijunction solar cells,” High-Efficiency Crystalline Photovoltaics Group's principal scientist John Geisz said.
The record-setting cell
To create the record-setting cell, the NREL team used III-V materials that have a wide range of light absorption properties. III-V is a family of alloys created by combining the periodic table elements in group III from group V.
Every cell in the six junctions is specifically designed to capture the light from a certain portion of the solar spectrum. The team’s solar technology contains 140 total layers of III-V materials to support the performance of the six junctions.
NREL III-V Multijunction Group’s scientist and co-author Ryan France also shares how the six-junction solar cell is ideal to be used in concentrator photovoltaics (CPV), a special high-efficiency system technology in PV technologies. He went on to say that a way to reduce the cost of the technology is to cut the required area achieved by using a mirror that will capture the light and focus it to a point. That way, less semiconductor material is used.
|To create the record-setting cell, the NREL team used III-V materials that have a wide range of light absorption properties. / Photo by anatoliy_gleb via Shutterstock|
France believes it is “very achievable” to surpass the 50% efficiency although the 100% efficiency may not be possible because of the fundamental limits of thermodynamics, a branch of physics that deals with temperature and heat and their relation to energy, properties of matter, and work radiation.
The more efficient the solar technology is, the more scientists can shrink the panel size but still keep the same energy production. This would also mean that the technology will be more affordable to consumers, and the solar panel can be shaped in complicated or tiny surfaces but can still provide more power. Growth in the adoption of solar power is led by falling prices. The cost of installing solar technology in the US, for instance, dropped by more than 70% in the last decade. From the price of $40,000 for an average-sized residential solar technology, it dropped to roughly $18,000, and it paved the way for the industry to deploy the systems to many areas and expand new markets.
The NREL researchers believe that the main hurdle to top the 50% efficiency is the lessening of the resistive barriers in the photovoltaic cell that that hinders the flow of current. The team’s study also appeared in research news platform Science Daily.
While fossil fuels, namely coal, natural gas, and crude oil, are the major sources of energy in the world, solar power also makes up 14.9% of the total renewable consumption in the US alone. Solar power further remains the third most important renewable energy resources after hydro and wind in terms of installed capacity in the world.
Countries with the highest installed capacity of solar PV power
In statistics provided by solar panel guide platform Energy Informative and using data from European Photovoltaic Industry Association (EPIA), Germany has the highest installed capacity of solar PV power in the world at 32,411 MV. It is followed by Italy (16,361 installed PV), China (8,300), USA (7,777), Japan (6,914), Spain (5,166), France (4,003), Belgium (2,650), Australia (2,650), and Czech Republic (2,072).
The reason why Germany is the number one in the world with the highest capacity of solar PV power is not that the country has an incredible amount of energy. Instead, it has a great subsidizing framework that makes sure that solar power can compete in the market.
Solar PV energy consumption, by region
The Asia Pacific accounts for more than half of the global energy consumption coming from fossil fuels as well. It also consumed 314.21 terawatt-hours (TWh) of solar energy, the highest among other regions in 2018. It is followed by Europe, which consumed 139.05 TWh solar PV energy, North America (02.91 TWh), South and Central America 1(2.43 TWh), Middle East (6.12 TWh), and Commonwealth of Independent States (0.88 TWh), according to Our World in Data, a scientific online publication that focuses on large global problems.
There are many reasons why some people go solar, such as cutting energy costs and helping the environment. Some recognize it as a great home efficiency upgrade. It also increases the value of the property, boosts the country’s energy independence, and help the local economy by creating jobs.
Renewable energy and economic opportunity
The Solar Foundation, a nonprofit organization dedicated to advance the use of solar and solar-compatible technologies worldwide, shares that the United States solar industry employed 249,983 workers in 2019 from 244,340 in 2018. Nationwide, 11,583 are employed in the operations and maintenance, 29,798 in wholesale trade and distribution, 34,423 in manufacturing, and 162,126 in installation or project development. Women make up 26% of the solar workforce.
The number of home solar panels is projected to more than double by 2024 and the technique used in the III-V solar technology has the potential to revolutionize the solar industry.