Skip navigation to main content.
NREL - National Renewable Energy Laboratory
About NRELEnergy AnalysisScience and TechnologyTechnology TransferTechnology DeploymentEnergy Systems Integration

Solar Energy Basics

Photo of a solar electric system in Colorado with snow-covered mountain peaks in the background.

Solar panels installed on a home in Colorado.

Solar is the Latin word for sun—a powerful source of energy that can be used to heat, cool, and light our homes and businesses. That's because more energy from the sun falls on the earth in one hour than is used by everyone in the world in one year. A variety of technologies convert sunlight to usable energy for buildings. The most commonly used solar technologies for homes and businesses are solar water heating, passive solar design for space heating and cooling, and solar photovoltaics for electricity.

Businesses and industry also use these technologies to diversify their energy sources, improve efficiency, and save money. Solar photovoltaic and concentrating solar power technologies are also being used by developers and utilities to produce electricity on a massive scale to power cities and small towns.

Concentrating Solar Power 

These technologies harness heat from the sun to provide electricity for large power stations.

Passive Solar Technology 

These technologies harness heat from the sun to warm our homes and businesses in winter.

Solar Photovoltaic Technology 

These technologies convert sunlight directly into electricity to power homes and businesses.

Solar Water Heating 

These technologies harness heat from the sun to provide hot water for homes and businesses.

Solar Process Heat 

These technologies use solar energy to heat or cool commercial and industrial buildings.

NREL conducts research in the following solar technologies: