One of the features to look for when buying a solar panel is the solar cell efficiency. In short, this is the amount of electricity made out of sunlight absorbed by a pv panel. The higher the percentage of sunlight transformed into current via the photovoltaic effect, the more electricity you get out of your solar rooftop. Let’s have a look at how this works exactly.
Understanding solar cell efficiency
To get the most out of solar power, it’s important to understand how efficient solar cells are. At its core, efficiency is about how much sunshine a solar cell can turn into energy that can be used. This depends on many things, like the materials used, how it’s made, and where it’s used.
Silicon is the most common material for solar cells because it works well and is reliable. Researchers are looking into other materials, such as cadmium telluride, copper indium gallium selenide, and perovskite, to improve efficiency.
The way a solar cell is built also affects how well it works. Even though solid silicon cells work better, they cost more. Thin-film cells work less well but are cheaper.
Temperature and shade are two environmental factors that can affect how well solar cells work. High temperatures can hurt efficiency, and close buildings or trees can make it harder for the plant to get enough sunlight.
To choose the right solar panel, you need to think about a lot of things, like the materials, the way it’s made, and the weather.
What is good solar cell efficiency?
Good solar cell efficiency is typically defined as an efficiency level that is higher than the average efficiency of solar cells in the market. The average efficiency level of commercially available solar cells is around 15-20%. Therefore, any solar cell with an efficiency level higher than 20% can be considered to have good solar cell efficiency. However, the definition of good solar cell efficiency can vary depending on the specific application or industry. For example, in the space industry, solar cells with an efficiency level of around 30% or higher are considered to have good solar cell efficiency.
What affects solar cell efficiency?
It is important to know though, that these numbers are obtained by tests in laboratories. Getting 40% of solar cell efficiency in perfect lab conditions does tell you that those solar panels are more efficient than the ones that got 20% in the same conditions. In order to give a number to the efficiency of solar panels, it is important to do this in lab conditions. The image above shows the efficiency ratings obtained by research over time, the rising lines means that the efficiency is increasing.
It would be unfair if one panel was measured on a sunny day, getting a high percentage while an equally good panel would get a lower number just because of the weather conditions. But be aware, that these given percentages don’t mean that you will get 40% as well when getting a solar power installation on your house.
The position of the sun is a big factor in determining how efficient your panels will be. In the winter, the sun is lower than during the summer months. This different angle means the panels convert less of its light, lowering the solar cell efficiency.
Other weather factors influence the efficiency as well. On a cloudy day, your panels will generate less electricity than on a beautiful day when the sun is the only thing out there in the clear blue sky.
| Factors | Description |
| Materials used | The efficiency of a solar cell depends on the materials used in its construction. Silicon is the most commonly used material, but other materials like cadmium telluride, copper indium gallium selenide (CIGS), and perovskite are being studied to improve efficiency. |
| Design | The design of a solar cell also impacts its efficiency. Crystalline silicon cells are more efficient but more expensive than thin-film cells. |
| Operating environments | Environmental factors like temperature and shading can also impact solar cell efficiency. |
| Conversion efficiency | Not all sunlight that reaches a solar cell is converted into electricity. In fact, most of it is lost. |
| Good solar cell efficiency | Good solar cell efficiency is typically defined as an efficiency level higher than the average efficiency of solar cells in the market, which is around 15-20%. |
Environmental Impact of High Solar Cell Efficiency
While solar cells offer great promise as a clean energy source, their environmental effect may grow in tandem with their increased efficiency. The development of high-efficiency solar cells relies heavily on rare earth metals, which is a source of serious worry. The mining procedure for these metals is risky since it can contaminate land and water and destroy natural habitats.
The energy and materials used in their production also have an effect on the environment when it comes to high-efficiency solar cells. High temperatures, chemical processes, and power-hungry machinery are all part of the manufacturing procedure. In addition, solar panel manufacturing uses a lot of water, which is often in short supply in some areas.
Another issue is how to properly dispose of solar panels when they have served their useful purpose. Lead and cadmium, including in solar panels, can seep into the ground if the panels are not disposed of correctly. Unfortunately, solar panel recycling is still in its infancy, and it may be a costly and energy-intensive operation.
Sustainable and ethical manufacturing and disposal techniques for solar cells are crucial to reducing these negative effects on the environment. This involves minimizing the environmental impact of solar panel disposal by decreasing the usage of rare earth metals in manufacture, optimizing manufacturing processes to reduce energy consumption and waste, and establishing efficient recycling schemes. There should also be an emphasis on finding sustainable alternatives to silicon for solar cell manufacturing. Solving these problems is essential to ensuring that the manufacture of high-efficiency solar cells does not exceed the environmental advantages of solar energy.
Are solar cells being used in all solar devices?
Yes, solar cells are utilized in every solar-powered device, including solar watches, solar generators, and solar outdoor lights and lanterns. The fundamental components of solar technology, which uses the sun’s energy to produce electricity, are called solar cells.
Here is a list of our favourite solar devices on the market.
| Device | Best Feature | Description |
| Jackery Solar Generator | Emergency Power Backup | A portable and robust solar generator that includes a 100-watt solar panel and a 1000-watt-hour capacity. It can run lights, fans, and electronics for an extended period, and fully charge in around 8 hours. |
| BigBlue Solar Power Bank | High Capacity | A portable solar-powered charger with a 28W solar panel that can recharge the battery in just over 8 hours of direct sunlight. It can recharge your phone up to 26800 times. |
| YELOMIN Solar Battery | Budget-friendly | An affordable solar charger for your phone or other electronic devices. It includes a small solar panel that can charge the battery pack in a few hours of sunlight, providing you with enough power to charge your phone. |
| ABFOCE Bluetooth Solar | Wireless & Convenient | A solar-powered Bluetooth speaker suitable for outdoor activities. It comes with a high-quality solar panel that can charge the speaker in just a few hours of sunlight. You can connect it to your smartphone and enjoy your favourite music on the go. |
| Solgaard Solarbank | Rechargeable Anywhere | A lightweight and high-quality solar-powered portable battery pack. You can power your phone and other electronics from the battery pack, which can be charged in around 4 hours of direct sunlight. It is waterproof, making it suitable for outdoor use. |
| X-DRAGON Solar Charger | Portable & Durable | A high-quality solar charger with a 20W solar panel. It is water-resistant and can charge the battery pack in about 4 hours of sunlight, giving you enough power to charge your phone and other electronic devices. |
| Solgaard Lifepack | Sustainable Materials | A backpack with a solar panel integrated into the design. The battery pack can be charged in a few hours of sunlight, and you can power your phone and other electronics on the go. The backpack is constructed from post-consumer plastic bottles, making it an eco-friendly choice. |
| Solarbank Boombox | Portable & Waterproof | A portable Bluetooth speaker with a high-quality solar panel that can charge the battery pack in just a few hours of sunlight. The battery can power the speaker for hours, and it is water-resistant, making it ideal for outdoor use. |
| Solar-powered Fans | Summer Classic | Due to improvements in solar technology, solar-powered fans are now available in small, portable designs that can be used on the go. This makes them a great choice for camping, hiking, and other outdoor activities. |
| Portable Solar Water Heater | Cook Anywhere | Typically, these water heaters are designed for outdoor activities that require hot water, such as camping, hiking, and other outdoor pursuits. They are portable and compact, making them ideal for use in remote areas with limited access to electricity or gas. |
The Future of Solar Cell Efficiency: Trends and Innovations
With so many promising new developments, the future of solar cell efficiency is bright. Perovskite solar cells, which have proved to attain high efficiency levels while simultaneously being low-cost and easy-to-manufacture, are one of the most promising prospects.
Tandem solar cells, which employ two or more different types of material to absorb more of the sun’s radiation and boost efficiency, are another popular option. Nanotechnology is gaining popularity as a means to increase the surface area of solar cells and decrease their reflection of light, hence enhancing the cells’ efficiency.
Researchers are investigating the possibility of using AI and ML to fine-tune solar cell designs for maximum efficiency. Finding the optimal mix of material qualities, environmental parameters, and other variables for a given application requires the use of algorithms to evaluate large amounts of data.
It is anticipated that the future efficiency of solar cells will be much enhanced by these trends and breakthroughs, which will also make solar energy more widely available and affordable.