Solar energy is radiant light and heat from the Sun that is harnessed using a range of technologies such as solar power to generate electricity, solar thermal energy including solar water heating, and solar architecture. The large magnitude of solar energy available makes it a highly appealing source of electricity. Solar energy has been cheaper than fossil fuels since 2021.
What are the specific technologies used to harness solar energy?
There are several specific technologies used to harness solar energy. Here are some of the most common:
- Photovoltaic (PV) Systems: These are the most common type of solar technology and what most people think of when they hear “solar power.” Photovoltaic systems use solar cells (usually silicon) to convert sunlight directly into electricity through the photovoltaic effect. The solar cells are grouped to form solar panels, and multiple panels can be connected to form a solar array.
- Concentrated Solar Power (CSP): This technology doesn’t use solar cells. Instead, it uses mirrors or lenses to concentrate a large area of sunlight onto a small space. The concentrated light is then used as a heat source for a conventional power plant. There are several types of CSP systems, including parabolic troughs, solar power towers, and dish/engine systems.
- Solar Heating and Cooling (SHC): These technologies use solar energy to heat or cool air and water for use in homes and businesses. This category includes solar water heaters, solar air heaters, and solar cooling systems. Solar water heaters, for example, use solar collectors to absorb solar radiation and heat water, which can then be used in your home or business.
- Solar Lighting: This involves using sunlight for illumination. For example, daylighting systems collect and distribute sunlight to interior spaces, reducing the need for artificial lighting. Solar lamps and lanterns convert solar energy into electrical energy, storing it in batteries for use when needed.
- Solar Thermal Electricity: Similar to CSP, this technology uses solar energy to generate heat and produce electricity. However, instead of concentrating the sunlight, solar thermal systems usually use flat solar collectors that directly absorb the Sun’s heat.
- Solar Fuels: This relatively new and developing technology uses solar energy to produce fuels. For example, artificial photosynthesis systems use sunlight to split water into hydrogen and oxygen, which can then be recombined in a fuel cell to produce electricity.
Each of these technologies has its own advantages and disadvantages, and the best choice depends on factors like the available sunlight, the specific energy needs, and the available budget.