Photovoltaics

Definition

Photovoltaics is the technology that converts sunlight directly into electricity using semiconductor materials. This process involves the absorption of photons, which leads to the excitation of electrons and results in the generation of electric current. Photovoltaics plays a critical role in renewable energy, offering a clean and sustainable way to harness solar energy for various applications.

5 Must Know Facts For Your Next Test

1. The efficiency of photovoltaic cells varies based on factors like material used, temperature, and light intensity, with common silicon-based cells achieving efficiencies around 15-22%.
2. Photovoltaics rely on the photovoltaic effect, which is the creation of voltage or electric current in a material upon exposure to light.
3. The first practical photovoltaic cell was developed in 1954 by Bell Labs, marking a significant milestone in solar technology.
4. Photovoltaic systems can be installed on rooftops or in large solar farms, allowing for decentralized energy production and reducing reliance on fossil fuels.
5. The global market for photovoltaics has expanded rapidly, driven by technological advancements and decreasing costs, making solar energy more accessible.

Review Questions

• How does the photovoltaic effect work in converting sunlight into electricity?
  • The photovoltaic effect involves the absorption of sunlight by semiconductor materials, leading to the excitation of electrons. When photons hit the semiconductor, they transfer energy to electrons, allowing them to break free from their atomic bonds. This movement creates an electric current as these free electrons flow through the material, ultimately generating electricity that can be harnessed for use.
• Compare the efficiencies of different types of photovoltaic materials and their implications for solar energy production.
  • Different types of photovoltaic materials exhibit varying efficiencies; for instance, monocrystalline silicon cells typically offer higher efficiencies compared to polycrystalline cells due to their uniform structure. Thin-film solar cells are less efficient but can be produced at a lower cost and are flexible, allowing for innovative applications. Understanding these differences helps inform choices about which type of photovoltaic technology to use based on factors like cost, available space, and desired energy output.
• Evaluate the impact of advancements in photovoltaic technology on the renewable energy landscape and global sustainability efforts.
  • Advancements in photovoltaic technology have significantly transformed the renewable energy landscape by improving efficiency and reducing costs. Innovations such as bifacial solar panels and perovskite solar cells have emerged, pushing the boundaries of what is possible in solar energy production. As these technologies become more prevalent, they contribute to global sustainability efforts by providing cleaner energy alternatives, reducing greenhouse gas emissions, and promoting energy independence, which is essential for combating climate change.

Related terms

Semiconductor: A material that has electrical conductivity between that of a conductor and an insulator, essential for the functioning of photovoltaic cells.

Solar Cell: A device made from semiconductor materials that converts sunlight into electrical energy through the photovoltaic effect.

Photons: Elementary particles of light that carry energy and are essential in the photovoltaic process as they excite electrons in semiconductor materials.