How Does Solar Energy Work?

Written By Teacher: Meighan Hooper

Meighan has been an arts educator and instructional designer since 2007. Originally from Ontario, Canada, she began teaching internationally in the Middle East and Asia in 2013. Meighan has designed programs of study based on a variety of curriculum including Canadian, American standards-based, Primary Years Program (IB), and British National curriculum.

With solar panels appearing in more places every day, it’s a perfect time to teach students about how solar energy works. Start by explaining how solar panels convert sunlight into electricity through photovoltaic cells, a process that turns light energy into electrical energy without any moving parts. Emphasize solar energy’s role as a renewable, clean power source that reduces greenhouse gas emissions. For a hands-on lesson, try the "Making a Solar Oven" activity, where students can build their own solar ovens to explore solar thermal energy. For early learners, consider the "Sun Lesson for Kids", which introduces the sun’s energy through simple, engaging activities that help them understand the sun’s importance to life on Earth. These resources make learning about solar energy accessible and exciting for all ages!

Written By: MIT Environmental Solutions Initiative

The MIT Climate Change Engagement Program, a part of MIT Climate HQ, provides the public with nonpartisan, easy-to-understand, and scientifically-grounded information on climate change and its solutions.

Solar energy is a form of renewable energy, in which sunlight is turned into electricity, heat, or other forms of energy we can use. It is a “carbon-free” energy source that, once built, produces none of the greenhouse gas emissions that are driving climate change.

Solar is the fastest-growing energy source in the world, adding 270 terawatt-hours of new electricity generation in 2022: enough to power a midsize state like North Carolina or Michigan, or a small wealthy country like Denmark or Ireland.

The solar photovoltaic effect

There are several ways to turn sunlight into usable energy, but almost all solar energy today comes from “solar photovoltaics (PV).”

Solar PV relies on a natural property of “semiconductor” materials like silicon, which can absorb the energy from sunlight and turn it into electric current. When light hits a semiconductor, it knocks the electrons in the semiconductor’s atoms loose. The electrons then move freely until they find another atom that can take them in, generating an electric field that forces electrons to flow in a specific direction.

The solar panels (“modules”) you see on homes and in solar farms are made of many “cells” of silicon or other types of semiconductor, which constantly absorb light and release electrons. The cells are specially treated and arranged so the free electrons, the “electric charge,” all move in the same direction. This creates an electrical current that can be used to power homes, electric vehicles, and anything that runs on electricity.