What are solar cells?
What Are Solar Cells?
When someone talks about renewable power, the first thing most people think about is solar power. We’ll explain the benefits of solar panels and how they work.
Solar panels are the primary way we harness solar energy. It converts solar energy into electricity through photovoltaic power. Less common forms of solar power tend to collect heat; in these cases, it heats water so that other sources of energy aren’t required for that purpose.
The solar cells absorb sunlight, and an anti-reflective coating promoting maximal energy absorption. No solar panel collects 100% of the solar power. Instead, it captures the light, and a modest percentage passes through two layers of semiconductors with opposite charges. The semiconductors convert about ten to twenty percent of the energy to electricity. Cheaper multi-crystal solar cells have lower efficiency rates but cost less.
It was notable when one company’s tests came up with nearly 30% efficiency, but most convert around 20% of the solar energy they absorb into power. Those figures are for silicon solar panels, whereas carbon-based cells and organic cells are much less efficient. Research is underway to make them as effective as silicon solar panels.
The relatively low conversion rate of each solar panel cell explains why solar cells are joined in arrays.
The performance of solar panel arrays and their efficiency depend on:
• The size of the system
• The amount of sunlight received
• The intensity of the sunlight
• Any obstructions to the reception of sunlight such as clouds, shade or caked on dirt
The Benefits of Solar Power
Hydropower is the cheapest renewable power, but that’s only because the massive infrastructure costs are already paid for. It isn’t more common, though, because it depends on continual water supply and geography. Wind power is fast-growing, but it faces some geographic limitations as well, though not as much as hydroelectric. The only source of renewable energy that can be set up almost anywhere is solar power. And that’s achieved through solar panels.
Solar power can be set up dry areas and places with mild winds. The solar panel is available on a daily basis, whereas wind power tends to be generated during sunrise and sunset, during the spring and fall. In short, wind power is most abundant in many places when it is least needed. Solar power is highest during the day, often peaking in the summer when air conditioning power is most desperately needed. The fact that you can tap into solar power on the road or your roof without the tall, expensive wind turbines is a bonus.
Solar powers can be portable. You can fasten them to the roof of an RV and take them with you to generate at least some energy for lights and recharging house batteries. In other cases, you can use solar panels to recharge camping lamps and cell phones at campsites. And you can install them on the roof of your home pretty much wherever you live. The only limitation is going to be the design of the roof; it must be able to hold the weight of the solar panels and sit at an angle that can support solar panels. We don’t yet have the ability to mount solar panels that replace roof tiles. However, solar panels are more durable than in years past including a protective coating.
Tougher solar cells designed for building roadways that can also generate power would also be suitable for installation on roofs in place of conventional roofing materials. Transparent solar panels are under development, and that could allow for widespread replacement of windows with solar panels.
Solar panels are relatively easy to use once set up, though battery management is an issue. However, they require far less maintenance than wind turbines.
The Limitations of Solar Power
There are limitations to solar power. It doesn’t produce power 24×7, and that requires a significant investment in batteries. Solar power doesn’t need as much water as hydroelectric, but they do require maintenance like cleaning of dirt and debris. Solar panels can be expensive, though that cost can be defrayed by tax deductions and utility credits. As the technology matures, the cost per solar panel is coming down.
Solar power is a proven, versatile renewable energy technology. There are a number of advancements in solar tech that will expand the ways it can be generated and allow for broader adoption.
You can learn more about the developments in solar panel tech at www.iqsdirectory.com/resources/what-are-solar-cells-everything-you-wanted-to-know/.