Solar energy covers all of the power that comes from the sun. Most people picture solar panels when they think about solar energy, but those are not the only tools that humans have developed to harvest that energy.
There are three broad categories that cover most solar energy technologies. If you are considering investing in solar power, consider the following options:
Photovoltaic cells are the most popular choice by a significant margin, making up more than 90 percent of all solar power installations. They are the little black panels that most people picture when they think about solar power and are very good at turning sunlight into electricity.
Photovoltaic cells date back to the 1940s, however, the principle that allows them to work was discovered way back in the 19th century. Modern panels are much more efficient than the older ones, so people can usually recover the cost of installing them on a roof or near a home within a few years if they are in a reasonably sunny environment. Since the cost of maintaining the panels after installation is negligible, small installations are becoming more popular. That’s great news for the environment, since rooftop installations alone are estimated to be able to cover about 40 percent of America’s energy usage on their own!
Solar heating systems have been in use for centuries. Modern technology has made them more efficient, but the core mechanisms are ancient. They use sunlight to provide heat without turning it into electricity or using any other intermediate steps. That is incredibly efficient and it’s possible to do it with systems that are small, cheap, and easy to maintain.
For example, a simple solar water heater works by running pipes of water through a dark collector that conducts heat into the water before it goes into the home. As long as it is positioned in a place that gets plenty of sunlight, it will heat up to acceptable levels while the sun is out. Because water retains heat, it will remain warm even after the sun sets. These systems are useful because the cost of heating buildings can be quite expensive.
Concentrated solar generators are the most complicated system. They use a set of reflectors to concentrate sunlight to a single area, which is usually a container of water or molten salt. The substance boils and the steam rotates a turbine to generate electricity. This is similar to how conventional power plants work, but they use sunlight to produce steam instead of fossil fuels or a nuclear reactor. They’re incredibly powerful systems, but they are also large projects. Plenty of governments are starting to invest in them to replace older power plants, but it’s best to use the other two options for powering homes.